CA2113310A1 - Process for maintaining or improving the mechanical properties of fibers of aromatic copolyamides in alkaline media and shaped articles containing such fibers - Google Patents
Process for maintaining or improving the mechanical properties of fibers of aromatic copolyamides in alkaline media and shaped articles containing such fibersInfo
- Publication number
- CA2113310A1 CA2113310A1 CA 2113310 CA2113310A CA2113310A1 CA 2113310 A1 CA2113310 A1 CA 2113310A1 CA 2113310 CA2113310 CA 2113310 CA 2113310 A CA2113310 A CA 2113310A CA 2113310 A1 CA2113310 A1 CA 2113310A1
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- formula
- structural units
- fibers
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B16/00—Use of organic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of organic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B16/04—Macromolecular compounds
- C04B16/06—Macromolecular compounds fibrous
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
- D01F6/00—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof
- D01F6/78—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolycondensation products
- D01F6/80—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolycondensation products from copolyamides
- D01F6/805—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolycondensation products from copolyamides from aromatic copolyamides
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- D—TEXTILES; PAPER
- D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
- D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
- D06M11/00—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising
- D06M11/32—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising with oxygen, ozone, ozonides, oxides, hydroxides or percompounds; Salts derived from anions with an amphoteric element-oxygen bond
- D06M11/36—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising with oxygen, ozone, ozonides, oxides, hydroxides or percompounds; Salts derived from anions with an amphoteric element-oxygen bond with oxides, hydroxides or mixed oxides; with salts derived from anions with an amphoteric element-oxygen bond
- D06M11/38—Oxides or hydroxides of elements of Groups 1 or 11 of the Periodic System
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
- Y10T428/2913—Rod, strand, filament or fiber
- Y10T428/2933—Coated or with bond, impregnation or core
- Y10T428/2964—Artificial fiber or filament
- Y10T428/2967—Synthetic resin or polymer
- Y10T428/2969—Polyamide, polyimide or polyester
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/31504—Composite [nonstructural laminate]
Abstract
Abstract of the Disclosure A process for maintaining or increasing the tensile strength of fibers of aromatic copolyamides which are built up chiefly from para-monomers and are soluble in organic aprotic and polar solvents in the course of storage in alkaline media is described. The process comprises the measures:
a) production of fibers from the said aromatic copolyamides by dry or wet spinning processes which are customary per se, b) after-treatment of the resulting fibers in a manner which is known per se, and c) storage of the fibers in an aqueous environment which has a pH of at least 10 for at least a period of time and at a temperature such that the tensile strength of the said fibers, based on the tensile strength of the fibers employed in step c), is at least retained or increased.
a) production of fibers from the said aromatic copolyamides by dry or wet spinning processes which are customary per se, b) after-treatment of the resulting fibers in a manner which is known per se, and c) storage of the fibers in an aqueous environment which has a pH of at least 10 for at least a period of time and at a temperature such that the tensile strength of the said fibers, based on the tensile strength of the fibers employed in step c), is at least retained or increased.
Description
A hl ~ 3 0 HO~CHST ARTIENGESELLSC~AFT HOE 93/F 013 Dr.AC/wo De~cription Process for maintaining or improving the mechanical properties of ~ibers of aromatic copolyamides in alkaline media and ~haped artlclea containing ~uch ~ibers The present ~nvention relates to a proce~s for maintain~
ing or improving the mechanical propsrtie~ o$ f iber~ of aromatia copolyamides in alkaline media, i.e. maintaining or incr0a~ing the ~iber tenaile atre~gth, and tho~e ahaped articles containing auch ~iber~ and hydraulically setting inorganic material~
Aromatic polyamide~ (called aramid~ below) are known aB
fiber-forming polymera having a good re~istance to chemical~. Fiber~ of aramids which are built up chiefly rom para-monomers furthermore are diatingul~hed by good mechanical properties, ~uch aa high ten~ile ~trength~ and elasticity moduli.
The re~i~tance of commercially available ~iber~ of aramids to acid an~ alkali somet~me~ leaves om0thing to be de~ired, ~o that ~uch fiber~ cannot be employed without re~ervation for the production of co~po~ite material~ which contain atrongly acid or alkaline matrix material~ Thc drop in ten~ile ~trength o ~ibsr~ o~ such aramids when atored in atrongly acid or alkaline m~dia, such a3 ~ulfuric acid or ~odium hydroxide ~olution, i~
explained by partiPl hydroly~i~ o~ the amide bonds o~ the polymer (c~. ~.H. Yang, Aromatic Xigh-Strength Fibera, page~ 248-251 and pages 274~276, J. Wiley & Sonn~.
Neverthele~, aramid fibere have already been di~clo~ed which have a re~istance to acid and alkala which i~
¦ improved compared with conv0ntional aramid fiber~ and a low moiature uptake and the uae o~ which for reinforcing cement has already been propo~ed (c$. Te¢hniache Textilien, Volume 35, October 1992, T123~T132).
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~33~
It han now been found that fiber~ of certain aromatic copolyamides which are built up chie~ly from para-monomers and are 801uble in organic aprotic and polar solvents have their tensile strength and other mechanical properties, æuch a~ ~odulus or elongation at break, maintained or inoreased by treatment with ~trongly alkaline environment~
Thia behaviour i8 all the more surpri~ing ~ince, on the ba~i~ of experience with para-aramid~ which are already known and are eoluble only in a~gre~ive media, ~uch a~
in concentrated ~ulfuric ac~d, an increa3e or maintenance of the mechanical propertiec with time in a Btrongly alkaline environ~ent had not been expected but, in contrast, a decrease in the~e properties.
The pre~ent invention relate~ to a process for maintain~
ing or increa~ing the ten~ile Rtrength of fiber~ of aromatic copolyamide~ which are built up chiafly _rom para-monomers and are ~oluble in organic aprotic and polar 801vent8 in the cour~e of ~torage in alkaline media, comprising the ~ea~uree:
a) production of fibern from the said aromatic aopoly-amide~ by dry or wet Epinning proCe~0es ~hich are ouctomary per ~e, b) after-treatment of the re~ulting fiber~ in a manner which is known per Be, and c) ~torage of the fibera in an aqueou~ environment which ha~ a p~ of at lea~t 10, preferably egual to or greater than 12, in particular 12 to 14, ~or at least a period of time and at a t~mperature ~uch that the ten~ile ~trength of the eaid fiber8, ba~ed on th~ t~naile ~trength of the ~ibors ~mployed in 8tep C), i8 at lsast retained or increa~ed.
The term "aromatic copolyamide which iæ built up chiefly from para-monomern and i~ ~oluble in organic aprotic and polar 301vent~" in the context of this invention i~
under~tood a~ meaning a copolymide which i~ eolubl0 in ~1~3~
3 _ conventional ~olvent~ for polyamides, for example in N-methylpyrrolidone, at 25C to the extent o~ at lea3t 4 ~;
to 12% by weight, particularly preferably to the extent - `
o~ 5.0 to 7.5% by weight, and which has at lea~t two aromatic diamine component~, in addition to at lea~t one aromatic dicarboxylic acid compone~t.
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. ,: . . .
The dicarboxylic acid component here is chiefly, in particular to the extent of more than 90 mol~, based on the total amount of dicarboxylic acid componsnt~ in the polymer, derived from divalent aromatic radicals in which the carboxyl group~ are in the para-position or compar~
able coaxial or parallel position. ;;
At least one o~ the diamine components furthermore i~
derived from divalent aromatic radiaals the amino groups of which are in the para-position or in a comparable coaxial or parallel po~ition; thi~ diamine component, which can also be a mixture of different diamines of thi~
type, i~ u~ually contained in the polymer to the extent of at least 50 mol%, ba~ed on the total amount of diamine component~ in the pol~mer, preferably to the extent of more than 60 mol%, ba~ed on the total amount of diamine component~ in the polymer.
At lea~t one of the dianine components i~ derived fro~
divalent aro~atic radiaals the 2mino groups o whioh are in the angled po3ition rslative to one another, ~or Qxzmple in the meta-po~ition or i~ a comparable an~led position relat~ve to one another; this diamine component, which can al~o be a mixture of variou3 diamine~ o~ this type, i~ u~ually conta~ned in the polymer to the extent of up to 50 mol%, based on the total amount o~ diamine component~ in the polymer, preferably to the exten~ of ~ ~;
lea~ than 40 mol%, based on the total amount of di~mine components in the polymer.
The term "cu3tomary dry or wet ~pinning proces~" in the context o~ thi~ invention iB to be under~tood a~ meaning 2~1~3~
- 4 ~
a production proce~ for spun fiber in which solution~
of the polymer in an organic aprotic and polar solvent are used during ~pinning in the broadest sen~e. ~xamples of the~e are dry ~pinning processe~, wet spinning 5 process2~ or dry wet-~et spinning proces~es. ~;
. ~
The term "after-treatment" in the context of this inven~
tion i~ to be under~tood as meaning after-treatments which are cu~tomary per se on the ~pun fibers, ~uch as stretching, fixing, washing, preparing and drying.
. ~ ; -,, , The period of time and t~mparature required ~or the storage i~ to be determined in each individual ca~e, it ~ ~;
being possible to u~e routine methodg.
The storage medium employed ~or the aramid fibers is usually an aqueous mixture compri~ing a etrongly alkaline inorganic material. ~xamples o~ these are mixtures of inorganic materials which set in air and/or by mean~ o$
water, in particular hydraulically setting material~. ~
:' :
The aramid fiber~ treat~d or to be treated accordi~g to the invention are pre~erably employed a~ a mixture with ~ -cement, mortar, concret~ or ~yp~um, if appropriate in combination with organic sealing agent~ - i.9. in build-ing material~ in the broadest ~en~e.
The storage medium is preferably an aqueou~ ~olution o$
an al~ali ~etal hydroxide having the pH de~ined above, in particular sodium hydroxide ~olution, or an aqueouc ~lurry or mixture o~ a hydraulically setting inorganic material, in particular cement or concrete.
An aqueou~ mixture of a hydraulically setting inorgania material in ecp2cially preferably u~ed as the ~torage medium, and 3torage i~ carried out after mixing in of the fiber~ and haping of the re~ulting ~haped mixturs.
., :. .
The ~tored aramid fiber~ are expo~ed to temperature~ of ~,'':
20 to 100C, in particular t~mperatures of 20 to 60C, in the stron~ly alkaline enviro~ment. The u~e temperatures of the reeulting ahaped art~cle~ can be, for example, between -50C and +60C.
The etorage period depends on tha conditio~c cho~en in the individual case, ~uch as pH of the storage medium and storage temperature. The $inal state o~ the lncrea~e of the $ibers i~ usually reached within a ~ew days. At higher temperature~, even houre can be ~ufficient.
No reduction in the ten~ile ~trength o$ the fiber~ occur~
during ~torage, instead the tensile ~trength o~ the fiber~ i~ ~ainta~ned or, in particular, increa~ed;
typical values of the increa~e are in the range ~rom 1 to 20%, pre~erably 2 to 10%.
i '~-..:
In addition to the tensile 6trength, the elongation at break o$ the fibers a~ a rule al~o increa~e~. Th~ elas-ticity modulus a0 a rule remains more or le~3 Gonstant.
Shaped article~ having high ~ompreseive ~trength and a high energy-ab~orbing ratio can be produced from the~e fiber~
Aramid ~iber~ which, before ~torage in the inorganic matrix, have a ten~ile ~trength of at lea3t 120 cN/tex, in part~cular 150 to 290 cN/tex, eepecially 150 to 250 sN/tex, and an ela tici~y ~odulua, based o~ 100%
elongation, of ~ore than 30 N/tex, in particular 45 to 100 N/tex, e~pecial~y 45 to 90 N/tex, ars pr~ferably employed in the proceas accordlng to the lnvention.
. .
Aromatic copolya~ide~ which are particularly pre~erably employed in the proce~ according to the i~vention are those which have an intrin~ic vi~co~ity o~ at lea~
2.4 dl/g, pre~erably 3.0 to 6.5 dl/g ~mea~ured on solu-tions of 0.5 g of polyamide in 100 ml of 98% ~tre~th by weight ~ulfuric acid at 25C~ and contain at lea~t the 3 3 ~
recurring ~tructural units of the formula~ I, II a~d XII
(-OC-Ar-CO-NH-Ar'-NH~
~ ''"`.' `'~ ~
R ,R
(-OC-Ar-CO-NH
~ Ar-C0-NH ~ ~' ~ NH ~) (III) in which -Ar- and -Ar'- are divalent organic radical~ in which the valency bonds are in th~ para-poaition or a comparable coaxial or parallel po ition relati~e to one another, R is a Cl-C~-alkyl radical, in particular methyl, a Cl-C4-alkoxy radiaal, in particular methoxy, or a chlorineatom, R' i~ an un~ub~tituted or alkyl-~ub~tituted methylene radical or a grouping -O-Ar-O-, in which -Ar- as0ume~ the m~anin~ def ined above, and the proportions of the recurrlng structural units I, II and III, ba~ed on the total amount of thsse structural unit8 in the polymer, lie within a range d~f~ned by the following corner points~
point Q corronponding to 5 mol~ of ~tructural u~it~ of the formula I, 45 mol% of structural units of the formula II and 50 ~ol~ of the atructural unit~ of ~he ~ormula III, point R cosre~ponding to 45 mol% of ~tructural unit~ o the ~orm~la I, 5 mol~ of ~tructural unit~ of the formula II and 50 mol~ of ~tructural unit~ of the formula III, point S correeponding to 60 mol% of atructural units of the for~ula I, 35 mol% of gtructural u~it~ o the formula II and 5 mol~ of ~tructural unit~ o~ tho ~ormula III, poin~ T corre~ponding to 20 mol~ of ~tructural unit~ of the ormula I, 75 mol% of structural unit~ of the ormula II and 5 mol% of structural unit~ of the formula III, and point U corr0~ponding to 5 ~ol~ o~ ~tructural unite o~
.
- 7 ~ 33~
the formula I, 80 mol% of structural units o~ the 40rmula -.
II and 15 mol% of ~tructural units of the formula III. ;~
Aramid~ of this type are known ~rom EP-A-l99,090, to which the pre~ent de3cription likewise relate~
' :~',.
Types of these aramids which are particularly pre~erably employed are tho~e in whlch -Ar- and -Ar'- are ~ N~ :~
1,4-phenylene, the aymbols R are methoxy or chlorine or, :~
in particular, methyl and R' is -0-1,4-phenylene-0-, the ~`
proportions o$ the amount~ of the securrin~ ~tructural units, ba~ed on the total amount o~ ~hese Etructural unite within the polymer, lying within the following ranges~
recurring structural unit of the formula I: 5 to 60 mol~
preferably 15 to 45 mol%, recurring ~tructural unit of the ~or~ula II: 5 to 80 mol%, preferably 20 to 70 mol~, and recurring structural unit of the for~ula III: 5 to 50 mol%, pre~erably 15 to 50 mol%.
Arom~tic copolyamides which are likewi~e particularly ~ ~ :
20 preferably employed in the proces~ according to the :
invention are those which have an intrin~ic vi~co~ity of -~
at lea~t 2.4 dl/g, prefsrably 3.0 to 6.5 dl/g (mea~ured on solutions o$ 0.5 g o~ polyamide in 100 ml of 98%
strength by weight sul~uric acid at 25C) and contain at lea~t the recurring ~tructural unit~ of the ~ormulae I, IV and V ::
~:
(~OC-Ar-CO-NH-~r'-NH~
::
(-OC~Ar-CO-llH ~ ~ ~ L NH-) (IV) (-OC-Ar-CO-NH ~ O ~ O ~ NH-) ~v) ~`
.~
~: `
: ' ,~' :: '.,', 3 ~
in which -Ar- and -Ar'- have the meaning~i defined above, and the proportion~ of the recurring structural unit~
IV and V, ba~ad on the total amount of theYe ~tructural unit~ in the polymer, lie within the following rangee: ;~
recurring etructural u~it of the formula ~: 40 to 65 mol~, preferably 45 to 55 mol%, recurring structural unit oi the formula IV: 5 to 55 mol%, preferably 35 to 45 mol%, and recurring ~tructural unit o the ~ormula V: 5 to 35 mol%, preferably 5 to 25 mol%.
Aramid~ of thie type are known from EP A-499,230, to which the present description likewi~e relatea.
Type~ of theee aramids which are particularly preferably employed are tho~e in which -Ar- and -Ar'- are 1,4-phenylene.
The aramid fibers can be ~tored in the form of chopped fibere, ~taple fibers or continuou~ filament~ ior carry-ing out the procees according to the invention. Staple fibera ha~e, for example, a htaple length o~ 1.5 to 48 mm, preferably 3 to 24i mm, in particular 4 to 12 mm.
Shaped articlee containing continuous ill~m~nts can be, for example, unid~rectionally rein orced shaped articles or shaped articlee reinforced by the windin~ proce~
. .
The proces~ according to the invention i~ not ~ubject to limitation~ in re~pect oi the fibar linear d~n~ity.
Typical 4iber linear deneit~ are above 1.0 dtex, prefer-ably in the range ~rom 1.7 to 15 dtex. ~ ~
: .
Continuouei ~ilamentEi are in general ctored ac multi-filament~i. The overall linear density thereu~ i3.
- 30 ty~ically in the range ~rom 220 to 18,400 dtex, pre$erably ~40 to 3360 dtex. It ha~ been $ound that the increa~e in strength ie more pronounic~d when multi-filament~ of higher ovsrall linear dennity~ are ~mployed, and for thie reason the use of ~uch multifilaments is l ~ r . . ~ ~ , " , : . : 1 f~ 5~ 3 ~
particularly preferred.
Staple fiber~ can be mixed into the matrix using conven-tional mixing units; thus, for example, staple fiber~ can be stored in the matrix of h.ydraulically setting materials by means of the positive mixere, plough share mixers and other such mixere which are cuRtomary in practi~e. The matrix i~ preferably in the orm of an inorganic material, ~uch as in the form of f~ne content~
such ae gypeum, cement or limastone flour, up to coaree constituente, such ae sand, gravel and stone The mixing into the inorganic material can be carried out in the dry or moint state.
Multifilaments can likewi~e be incorporated into the matrix by processee which are known per ~e, for example by etoring preahaped articlee of multifilamente with hydraulically setting materials; after setting, the~e give the de~ired ehaped article. These are preferably unidirectionally reinforced shaped articl~e or shaped articles reinforced by the winding procese.
It has furthermore been foun~ ~hat the ~aintena~ce or increaee in tensile ~trength i8 eeeantially retained during long-term ~torage. The i~provement in the proper-ties of the fibers can be utilized, in particular, in the production and u e o haped article~ which are produced from a co~bination of kh~ aramid fibere to be u~ed according to the invention and an aqueou~ mixture of a hydraulically eetting inosganic material. The inve~tion therefore al~o relaten to the ehaped article~ obtainable in thie manner.
The fibere treated or to be treated acaording to the invention can be employed fo~ the production of gypeum, cement, mortars, plastere, ecr0ed or aoncrete.
The following examplee illustrate khe invention without limiting it.
- 10 - ~1133~
General working in~truc~ion~
Multifilament~ which compri~e an ar~mid ba~ed on 100 mol~
of terephthalic acid, 25 mol% o para-phenylenadi~mine, 25 mol% of 1,4-bis(4-aminophenoxy)benzene and 50 mol% of 3,3'-dimethylbenzldine (aramid I) or ~n aramid ba~ed on 100 mol% of terephthalic acid, 50 mol% of para-phenyl-enediamine, 15 mol% of 1,4-bi~(4-aminopheno~y)benzene and 35 mol% of 3,4'-diaminodiphenyl ether (aramid II) are employed ln tha following example~.
The fiber tow ia produ~ed by a cu~tomary wet ~pinning process by ~pinning of a polymer solution in N-methyl-pyrrolido~e i~to a precipitating bath and after-treatment comprising washing, stretching and drying.
: `
Storage i8 carried out in cement filtrate: Portland Cement PZ 35 (200 g in 1 1 of water).
Examples 1-4:
A fiber tow of aramid I o~ overall linear den~ity 1680 dtex i8 ~tor~d for 24 hours in cement filtrate of pH 12.5 at ~arious temperature~. The ten~ile stre~gth~, moduli and elongatione at break of the ~pe~imen~ after storage are ~hown in Table 1. ~xample 1 shows the Yalues for the u~treated fiber.
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f~, .
~ ~ ~ 3 3 ~
Table 1~
Example No. 1 2 3 4 Storage temperature (C) - 22 60 95 Tensile strength (cN/tex) 204 221 226 230 5 Modulu~, (N/tex) 60.3 60.7 60.2 58.5 Elongation at break (~) 3.4 3.7 3.8 4.0 Exam~,les 5-8 A ~iber tow o' aramid I of c,verall linear den0ity 1100 dkex i~ ~tored for 24 hours in ~odiu~ hydr4xide ~olu'cio~ :
of various pH values at 60C. The ten~ile strens~ths, moduli and elongation at break of the apeci~en~, af'cer ~torage are ehown in Table 2. Example 5 F,how~ the values for the untreated f'iber.
Table 2:
' 15 Example No. 5 6 7 8 pH - 10 12 14 Ten~ile ~tre~gth (cN/tex) 196 203 201 207 Modulus (N/tex) 60.3 60.2 59.1 58~,5 ~longation at break (%) 3.5 3.6 3.6 3.8 20 Exam~,le.~ 9-12: :
A $iber tow o ar~mid I of overall linear density 1680 dtex i~ stored f or 24 hour~ in sodium hydroxide ~olution :
of variou~ pH value~ at 60C. The "cen~,ile 6trength3, ~moduli and elongation~ at break of th2 ~"pecimane a""'cer !25 storage are 6hown ~n Table 3. ~xample 9 ~hows the value~
~~or th- ~tr-at~d ~lbor.
: ~
,, , . . ,, ,, . ~ . . . . .
~ 3 ~ ~ ~
Table 3:
Example No. 9 10 11 12 pH - 10 12 14 Tensile ~trength (sN/tex) 204 207 229 231 5 Modulus (N/tex) 60.3 60.4 61.2 61.4 Elongation at break (~) 3.4 3.5 3.9 3.9 ExamPle~ 13-16:
A fiber tow of aramid II of overall linear density 1100 dtex is stored for 24 hour~ in ~odium hydroxide solution of variou~ pH values at 60C. The ten~ile ~trength~, moduli and elon~ations at break of the ~pecimen~ aftar ~torage are shown in Table 4. Example 13 show3 the values for the untreated iibe~.
, .
Table 4:
15 Example No. 13 14 15 16 pH - 10 12 14 :
T2nsile ~trength (cN/tex) 225 228 230 231 :.
Modulu~ (N/tex) 47.4 46 47 46 Elongation at break (%) 4.6 4.8 4.8 4.9 20 Example~ 17-20: .
A ~iber tow of aramid I of overall linear denaity 1100 dtex is ~tored for 24 hour~ in ce~ent f~ltrate o~ p~ 12.5 at variou~ t~mperatures. The tensile ~trangth~, ~oduli and elongation~ at brea~ o~ tha epo~imena a~ter ~torage are ~hown in Table 5. Exa~ple 17 shows the ~alues for the untreated iber.
?~113310 ~ ::
Table 5:
Example No. 17 18 19 20 Storage t~mperature (C) - 22 60 95 Tensile Gtrength (cN/te~) 196 206 213 211 Modulus (N/tex) 60.3 59.9 59-3 57.0 Elongation at break (%) 3.5 3.6 3.7 3.9 Examples 21-24:
A fiber tow of aramid II of overall linear den~ity 1100 dtex is stored for 24 hours in cament filtrate of pH 12.5 at ~arious temperaturee. The tensile ~trengths, moduli and elongation~ at break of the specimen~ after ~torage are ~hown in Table 6. Example 21 shows the value~ for the untreated fiber.
. .
. , Table 6:
15 Example No. 21 22 23 24 Storage temperature (C) - 22 60 95 Tensile strength (cN/tex) 225 230 229 225 Modulus (N/tex) 47.4 45.6 45.7 45.2 ~ ~
Elongation at break (~) 4.6 4.9 4.8 4.8 ~ -:, ~ .
Examples 25-35~
", ~.,, ',"
A fiber tow of aramid I of overal linear den~ity 1680 dtex i~ ~tored for a relatively long period of time in cement filtrate of pH 12.5 at 80C. Fiber ~po~lmen~ are ;~
taken f rom time to ti~e and their ~echanical properties are determined. The t2n8ile strength~, moduli and elongatione at break of th0 ~pecimens stored for ~arious period~ of time are shown in Table 7.
':
~.
~ hr~ ~ 1 3 3 1 0 .. .
Table 7:
Example no. 25 26 27 28 29 30 31 32 33 34 35 Storage time 0 1 2 3 4 5 9 15 20 26 30 (days) 5 Tensile 210 214 221 227 230 227 228 227 228 228 232 strength (cN/tex) Modul us 60.3 58.5 59 58.2 58.2 58.0 58.6 59.0 58.0 58.2 59.3(N/tex) 10 Elongation 3.4 3.8 3.9 4.0 4.0 4.0 4.0 3.9 4.0 4.0 4.0 at break (X) Examplee 36-46:
. .
A fiber tow of aramid I of overall linear den~ity 1100 dtex ~ stored for a relatively long period of time in cement filtrate of pH 12.5 at 80C. Fiber specimens are taken from time to time and their mechanical properties are determined. The tensile otrengths, moduli and elon-gation~ at break o4 the specimens ~tored for variou~
perioda of time are shown in Table 8.
Table 8~
Example no. 36 37 38 39 40 41 42 43 44 45 46 Storage tlme 0 1 2 3 4 5 9 15 20 26 30 (days) Tensile 201 209 211 206 211 212 212 210 209 212 213 strength (cN/tex) Modulus 60 58.0 57.0 58.0 58 58.8 59.3 57.4 57.9 58.1 58.2 (N/tex) Elongation 3.5 3.7 3.9 3.7 3.8 3.8 3.7 3.8 3.8 3.8 3.8 at break (X) 3xamples 47-57:
I A fiber tow of aramid II of overall linear den~ity 1100 dtex i~ etored ~or a relatively long period of tlme in cement filtrate of pH 12.5 at 80C. Fiber ~pe~iimena are taken 4rom time to time and their me~ihaniaal propertie~
are determined. The tensile 3trength~, moduli and elongatione at break of the ~pecim~ns ~tored for variou~
periods of time are ahown in Table 9.
3 1 ~
Table 9:
Example no. 47 4B 49 50 51 52 53 54 55 56 57 Storage time 0 1 2 3 4 5 9 15 20 26 30 (days) Tensile 212 220 215 214 218 215 225 221 217 225 221 :
strength (cN/tex) Modul lls 45 .1 45 . 0 44 . 0 45 . 0 44 . 0 44 .1 45 . 2 45 . 8 44 . 7 45 .1 44 . 2 (N/tex) 10 Elongatlon 4.7 4.5 4.7 4.5 4.7 4.7 4.8 4.6 4.7 4.8 4.7 at break (%) Exam~les 58-65:
Multifilament~ which comprise an aramid ba~ed on 100 mol%
of terephthalic acid, 50 mol% of para-phenylenediamine and 50 mol% of 3,4'-diaminodiphenyl ether were employed in the following exa~ple~
The multifila~ent ia a fiber tow wet-spun and after~
treated by the customary pro~ee~. Storage wan carried out in cement filtrate: Portland Cement PZ 35 (200 g in 1 1 20 of water). ~; .
~ ' ~ '.:~`.' '` .'.'' Example~ 58-61 A fiber tow o$ f~lament~ of the aramid characterized :~
above o o~erall linear den~ity 1700 dtex wa etored for 24 hour~ in ~ement ~ilt~ate o~ pH 12.5 at variou~
tamperatures. The ten~ile ~trength~, moduli and elongation~ at brsak o~ the ~pe~imen~ after storage are ahown in the ~ollowing table. ~xample 58 sho~3 ~he ~alue~
for the untreated ~iber.
:
- ~ f~ 3 3 ~
. - 16 -Example No. 58 59 60 61 Storage temperature (C) - 22 60 95 Ten~ile ~trength (cN/tex) 225 225 235 240 Modulu~ (N~tex) 60 60 60 60 5 Elongation at break (~) 4 4 4 4 Exam~le~ 62-65: .
";
A ~iber tow of filaments o~ the aramid charaaterized above o~ overall linear den~ity 1700 dtex was ~tored for 24 hours in ~odium hydro~ide solution of various pH
10 values at 60C. The tensile ~trengths, moduli and ~ ::
elongation~ at break of the specimen~ after storage are Ehown in the following table. Example 62 ehow~ the value~
~or the untreated fiber.
Example No. 62 63 64 65 15 pH - 10 12 14 Ten~ile strength (~N/tex) 225 230 245 245 Modulus (N/tex) 60 60 60 60 Elongation at break (~) 4 4 4 4 - ~-
ing or improving the mechanical propsrtie~ o$ f iber~ of aromatia copolyamides in alkaline media, i.e. maintaining or incr0a~ing the ~iber tenaile atre~gth, and tho~e ahaped articles containing auch ~iber~ and hydraulically setting inorganic material~
Aromatic polyamide~ (called aramid~ below) are known aB
fiber-forming polymera having a good re~istance to chemical~. Fiber~ of aramids which are built up chiefly rom para-monomers furthermore are diatingul~hed by good mechanical properties, ~uch aa high ten~ile ~trength~ and elasticity moduli.
The re~i~tance of commercially available ~iber~ of aramids to acid an~ alkali somet~me~ leaves om0thing to be de~ired, ~o that ~uch fiber~ cannot be employed without re~ervation for the production of co~po~ite material~ which contain atrongly acid or alkaline matrix material~ Thc drop in ten~ile ~trength o ~ibsr~ o~ such aramids when atored in atrongly acid or alkaline m~dia, such a3 ~ulfuric acid or ~odium hydroxide ~olution, i~
explained by partiPl hydroly~i~ o~ the amide bonds o~ the polymer (c~. ~.H. Yang, Aromatic Xigh-Strength Fibera, page~ 248-251 and pages 274~276, J. Wiley & Sonn~.
Neverthele~, aramid fibere have already been di~clo~ed which have a re~istance to acid and alkala which i~
¦ improved compared with conv0ntional aramid fiber~ and a low moiature uptake and the uae o~ which for reinforcing cement has already been propo~ed (c$. Te¢hniache Textilien, Volume 35, October 1992, T123~T132).
r.~r,.,~ .. "~
~33~
It han now been found that fiber~ of certain aromatic copolyamides which are built up chie~ly from para-monomers and are 801uble in organic aprotic and polar solvents have their tensile strength and other mechanical properties, æuch a~ ~odulus or elongation at break, maintained or inoreased by treatment with ~trongly alkaline environment~
Thia behaviour i8 all the more surpri~ing ~ince, on the ba~i~ of experience with para-aramid~ which are already known and are eoluble only in a~gre~ive media, ~uch a~
in concentrated ~ulfuric ac~d, an increa3e or maintenance of the mechanical propertiec with time in a Btrongly alkaline environ~ent had not been expected but, in contrast, a decrease in the~e properties.
The pre~ent invention relate~ to a process for maintain~
ing or increa~ing the ten~ile Rtrength of fiber~ of aromatic copolyamide~ which are built up chiafly _rom para-monomers and are ~oluble in organic aprotic and polar 801vent8 in the cour~e of ~torage in alkaline media, comprising the ~ea~uree:
a) production of fibern from the said aromatic aopoly-amide~ by dry or wet Epinning proCe~0es ~hich are ouctomary per ~e, b) after-treatment of the re~ulting fiber~ in a manner which is known per Be, and c) ~torage of the fibera in an aqueou~ environment which ha~ a p~ of at lea~t 10, preferably egual to or greater than 12, in particular 12 to 14, ~or at least a period of time and at a t~mperature ~uch that the ten~ile ~trength of the eaid fiber8, ba~ed on th~ t~naile ~trength of the ~ibors ~mployed in 8tep C), i8 at lsast retained or increa~ed.
The term "aromatic copolyamide which iæ built up chiefly from para-monomern and i~ ~oluble in organic aprotic and polar 301vent~" in the context of this invention i~
under~tood a~ meaning a copolymide which i~ eolubl0 in ~1~3~
3 _ conventional ~olvent~ for polyamides, for example in N-methylpyrrolidone, at 25C to the extent o~ at lea3t 4 ~;
to 12% by weight, particularly preferably to the extent - `
o~ 5.0 to 7.5% by weight, and which has at lea~t two aromatic diamine component~, in addition to at lea~t one aromatic dicarboxylic acid compone~t.
:, ..... ,~:
. ,: . . .
The dicarboxylic acid component here is chiefly, in particular to the extent of more than 90 mol~, based on the total amount of dicarboxylic acid componsnt~ in the polymer, derived from divalent aromatic radicals in which the carboxyl group~ are in the para-position or compar~
able coaxial or parallel position. ;;
At least one o~ the diamine components furthermore i~
derived from divalent aromatic radiaals the amino groups of which are in the para-position or in a comparable coaxial or parallel po~ition; thi~ diamine component, which can also be a mixture of different diamines of thi~
type, i~ u~ually contained in the polymer to the extent of at least 50 mol%, ba~ed on the total amount of diamine component~ in the pol~mer, preferably to the extent of more than 60 mol%, ba~ed on the total amount of diamine component~ in the polymer.
At lea~t one of the dianine components i~ derived fro~
divalent aro~atic radiaals the 2mino groups o whioh are in the angled po3ition rslative to one another, ~or Qxzmple in the meta-po~ition or i~ a comparable an~led position relat~ve to one another; this diamine component, which can al~o be a mixture of variou3 diamine~ o~ this type, i~ u~ually conta~ned in the polymer to the extent of up to 50 mol%, based on the total amount o~ diamine component~ in the polymer, preferably to the exten~ of ~ ~;
lea~ than 40 mol%, based on the total amount of di~mine components in the polymer.
The term "cu3tomary dry or wet ~pinning proces~" in the context o~ thi~ invention iB to be under~tood a~ meaning 2~1~3~
- 4 ~
a production proce~ for spun fiber in which solution~
of the polymer in an organic aprotic and polar solvent are used during ~pinning in the broadest sen~e. ~xamples of the~e are dry ~pinning processe~, wet spinning 5 process2~ or dry wet-~et spinning proces~es. ~;
. ~
The term "after-treatment" in the context of this inven~
tion i~ to be under~tood as meaning after-treatments which are cu~tomary per se on the ~pun fibers, ~uch as stretching, fixing, washing, preparing and drying.
. ~ ; -,, , The period of time and t~mparature required ~or the storage i~ to be determined in each individual ca~e, it ~ ~;
being possible to u~e routine methodg.
The storage medium employed ~or the aramid fibers is usually an aqueous mixture compri~ing a etrongly alkaline inorganic material. ~xamples o~ these are mixtures of inorganic materials which set in air and/or by mean~ o$
water, in particular hydraulically setting material~. ~
:' :
The aramid fiber~ treat~d or to be treated accordi~g to the invention are pre~erably employed a~ a mixture with ~ -cement, mortar, concret~ or ~yp~um, if appropriate in combination with organic sealing agent~ - i.9. in build-ing material~ in the broadest ~en~e.
The storage medium is preferably an aqueou~ ~olution o$
an al~ali ~etal hydroxide having the pH de~ined above, in particular sodium hydroxide ~olution, or an aqueouc ~lurry or mixture o~ a hydraulically setting inorganic material, in particular cement or concrete.
An aqueou~ mixture of a hydraulically setting inorgania material in ecp2cially preferably u~ed as the ~torage medium, and 3torage i~ carried out after mixing in of the fiber~ and haping of the re~ulting ~haped mixturs.
., :. .
The ~tored aramid fiber~ are expo~ed to temperature~ of ~,'':
20 to 100C, in particular t~mperatures of 20 to 60C, in the stron~ly alkaline enviro~ment. The u~e temperatures of the reeulting ahaped art~cle~ can be, for example, between -50C and +60C.
The etorage period depends on tha conditio~c cho~en in the individual case, ~uch as pH of the storage medium and storage temperature. The $inal state o~ the lncrea~e of the $ibers i~ usually reached within a ~ew days. At higher temperature~, even houre can be ~ufficient.
No reduction in the ten~ile ~trength o$ the fiber~ occur~
during ~torage, instead the tensile ~trength o~ the fiber~ i~ ~ainta~ned or, in particular, increa~ed;
typical values of the increa~e are in the range ~rom 1 to 20%, pre~erably 2 to 10%.
i '~-..:
In addition to the tensile 6trength, the elongation at break o$ the fibers a~ a rule al~o increa~e~. Th~ elas-ticity modulus a0 a rule remains more or le~3 Gonstant.
Shaped article~ having high ~ompreseive ~trength and a high energy-ab~orbing ratio can be produced from the~e fiber~
Aramid ~iber~ which, before ~torage in the inorganic matrix, have a ten~ile ~trength of at lea3t 120 cN/tex, in part~cular 150 to 290 cN/tex, eepecially 150 to 250 sN/tex, and an ela tici~y ~odulua, based o~ 100%
elongation, of ~ore than 30 N/tex, in particular 45 to 100 N/tex, e~pecial~y 45 to 90 N/tex, ars pr~ferably employed in the proceas accordlng to the lnvention.
. .
Aromatic copolya~ide~ which are particularly pre~erably employed in the proce~ according to the i~vention are those which have an intrin~ic vi~co~ity o~ at lea~
2.4 dl/g, pre~erably 3.0 to 6.5 dl/g ~mea~ured on solu-tions of 0.5 g of polyamide in 100 ml of 98% ~tre~th by weight ~ulfuric acid at 25C~ and contain at lea~t the 3 3 ~
recurring ~tructural units of the formula~ I, II a~d XII
(-OC-Ar-CO-NH-Ar'-NH~
~ ''"`.' `'~ ~
R ,R
(-OC-Ar-CO-NH
~ Ar-C0-NH ~ ~' ~ NH ~) (III) in which -Ar- and -Ar'- are divalent organic radical~ in which the valency bonds are in th~ para-poaition or a comparable coaxial or parallel po ition relati~e to one another, R is a Cl-C~-alkyl radical, in particular methyl, a Cl-C4-alkoxy radiaal, in particular methoxy, or a chlorineatom, R' i~ an un~ub~tituted or alkyl-~ub~tituted methylene radical or a grouping -O-Ar-O-, in which -Ar- as0ume~ the m~anin~ def ined above, and the proportions of the recurrlng structural units I, II and III, ba~ed on the total amount of thsse structural unit8 in the polymer, lie within a range d~f~ned by the following corner points~
point Q corronponding to 5 mol~ of ~tructural u~it~ of the formula I, 45 mol% of structural units of the formula II and 50 ~ol~ of the atructural unit~ of ~he ~ormula III, point R cosre~ponding to 45 mol% of ~tructural unit~ o the ~orm~la I, 5 mol~ of ~tructural unit~ of the formula II and 50 mol~ of ~tructural unit~ of the formula III, point S correeponding to 60 mol% of atructural units of the for~ula I, 35 mol% of gtructural u~it~ o the formula II and 5 mol~ of ~tructural unit~ o~ tho ~ormula III, poin~ T corre~ponding to 20 mol~ of ~tructural unit~ of the ormula I, 75 mol% of structural unit~ of the ormula II and 5 mol% of structural unit~ of the formula III, and point U corr0~ponding to 5 ~ol~ o~ ~tructural unite o~
.
- 7 ~ 33~
the formula I, 80 mol% of structural units o~ the 40rmula -.
II and 15 mol% of ~tructural units of the formula III. ;~
Aramid~ of this type are known ~rom EP-A-l99,090, to which the pre~ent de3cription likewise relate~
' :~',.
Types of these aramids which are particularly pre~erably employed are tho~e in whlch -Ar- and -Ar'- are ~ N~ :~
1,4-phenylene, the aymbols R are methoxy or chlorine or, :~
in particular, methyl and R' is -0-1,4-phenylene-0-, the ~`
proportions o$ the amount~ of the securrin~ ~tructural units, ba~ed on the total amount o~ ~hese Etructural unite within the polymer, lying within the following ranges~
recurring structural unit of the formula I: 5 to 60 mol~
preferably 15 to 45 mol%, recurring ~tructural unit of the ~or~ula II: 5 to 80 mol%, preferably 20 to 70 mol~, and recurring structural unit of the for~ula III: 5 to 50 mol%, pre~erably 15 to 50 mol%.
Arom~tic copolyamides which are likewi~e particularly ~ ~ :
20 preferably employed in the proces~ according to the :
invention are those which have an intrin~ic vi~co~ity of -~
at lea~t 2.4 dl/g, prefsrably 3.0 to 6.5 dl/g (mea~ured on solutions o$ 0.5 g o~ polyamide in 100 ml of 98%
strength by weight sul~uric acid at 25C) and contain at lea~t the recurring ~tructural unit~ of the ~ormulae I, IV and V ::
~:
(~OC-Ar-CO-NH-~r'-NH~
::
(-OC~Ar-CO-llH ~ ~ ~ L NH-) (IV) (-OC-Ar-CO-NH ~ O ~ O ~ NH-) ~v) ~`
.~
~: `
: ' ,~' :: '.,', 3 ~
in which -Ar- and -Ar'- have the meaning~i defined above, and the proportion~ of the recurring structural unit~
IV and V, ba~ad on the total amount of theYe ~tructural unit~ in the polymer, lie within the following rangee: ;~
recurring etructural u~it of the formula ~: 40 to 65 mol~, preferably 45 to 55 mol%, recurring structural unit oi the formula IV: 5 to 55 mol%, preferably 35 to 45 mol%, and recurring ~tructural unit o the ~ormula V: 5 to 35 mol%, preferably 5 to 25 mol%.
Aramid~ of thie type are known from EP A-499,230, to which the present description likewi~e relatea.
Type~ of theee aramids which are particularly preferably employed are tho~e in which -Ar- and -Ar'- are 1,4-phenylene.
The aramid fibers can be ~tored in the form of chopped fibere, ~taple fibers or continuou~ filament~ ior carry-ing out the procees according to the invention. Staple fibera ha~e, for example, a htaple length o~ 1.5 to 48 mm, preferably 3 to 24i mm, in particular 4 to 12 mm.
Shaped articlee containing continuous ill~m~nts can be, for example, unid~rectionally rein orced shaped articles or shaped articlee reinforced by the windin~ proce~
. .
The proces~ according to the invention i~ not ~ubject to limitation~ in re~pect oi the fibar linear d~n~ity.
Typical 4iber linear deneit~ are above 1.0 dtex, prefer-ably in the range ~rom 1.7 to 15 dtex. ~ ~
: .
Continuouei ~ilamentEi are in general ctored ac multi-filament~i. The overall linear density thereu~ i3.
- 30 ty~ically in the range ~rom 220 to 18,400 dtex, pre$erably ~40 to 3360 dtex. It ha~ been $ound that the increa~e in strength ie more pronounic~d when multi-filament~ of higher ovsrall linear dennity~ are ~mployed, and for thie reason the use of ~uch multifilaments is l ~ r . . ~ ~ , " , : . : 1 f~ 5~ 3 ~
particularly preferred.
Staple fiber~ can be mixed into the matrix using conven-tional mixing units; thus, for example, staple fiber~ can be stored in the matrix of h.ydraulically setting materials by means of the positive mixere, plough share mixers and other such mixere which are cuRtomary in practi~e. The matrix i~ preferably in the orm of an inorganic material, ~uch as in the form of f~ne content~
such ae gypeum, cement or limastone flour, up to coaree constituente, such ae sand, gravel and stone The mixing into the inorganic material can be carried out in the dry or moint state.
Multifilaments can likewi~e be incorporated into the matrix by processee which are known per ~e, for example by etoring preahaped articlee of multifilamente with hydraulically setting materials; after setting, the~e give the de~ired ehaped article. These are preferably unidirectionally reinforced shaped articl~e or shaped articles reinforced by the winding procese.
It has furthermore been foun~ ~hat the ~aintena~ce or increaee in tensile ~trength i8 eeeantially retained during long-term ~torage. The i~provement in the proper-ties of the fibers can be utilized, in particular, in the production and u e o haped article~ which are produced from a co~bination of kh~ aramid fibere to be u~ed according to the invention and an aqueou~ mixture of a hydraulically eetting inosganic material. The inve~tion therefore al~o relaten to the ehaped article~ obtainable in thie manner.
The fibere treated or to be treated acaording to the invention can be employed fo~ the production of gypeum, cement, mortars, plastere, ecr0ed or aoncrete.
The following examplee illustrate khe invention without limiting it.
- 10 - ~1133~
General working in~truc~ion~
Multifilament~ which compri~e an ar~mid ba~ed on 100 mol~
of terephthalic acid, 25 mol% o para-phenylenadi~mine, 25 mol% of 1,4-bis(4-aminophenoxy)benzene and 50 mol% of 3,3'-dimethylbenzldine (aramid I) or ~n aramid ba~ed on 100 mol% of terephthalic acid, 50 mol% of para-phenyl-enediamine, 15 mol% of 1,4-bi~(4-aminopheno~y)benzene and 35 mol% of 3,4'-diaminodiphenyl ether (aramid II) are employed ln tha following example~.
The fiber tow ia produ~ed by a cu~tomary wet ~pinning process by ~pinning of a polymer solution in N-methyl-pyrrolido~e i~to a precipitating bath and after-treatment comprising washing, stretching and drying.
: `
Storage i8 carried out in cement filtrate: Portland Cement PZ 35 (200 g in 1 1 of water).
Examples 1-4:
A fiber tow of aramid I o~ overall linear den~ity 1680 dtex i8 ~tor~d for 24 hours in cement filtrate of pH 12.5 at ~arious temperature~. The ten~ile stre~gth~, moduli and elongatione at break of the ~pe~imen~ after storage are ~hown in Table 1. ~xample 1 shows the Yalues for the u~treated fiber.
:' " ': '' ' ' ~ :, ,: . . . : : ~: . , : : : ( : ~: . ,:
f~, .
~ ~ ~ 3 3 ~
Table 1~
Example No. 1 2 3 4 Storage temperature (C) - 22 60 95 Tensile strength (cN/tex) 204 221 226 230 5 Modulu~, (N/tex) 60.3 60.7 60.2 58.5 Elongation at break (~) 3.4 3.7 3.8 4.0 Exam~,les 5-8 A ~iber tow o' aramid I of c,verall linear den0ity 1100 dkex i~ ~tored for 24 hours in ~odiu~ hydr4xide ~olu'cio~ :
of various pH values at 60C. The ten~ile strens~ths, moduli and elongation at break of the apeci~en~, af'cer ~torage are ehown in Table 2. Example 5 F,how~ the values for the untreated f'iber.
Table 2:
' 15 Example No. 5 6 7 8 pH - 10 12 14 Ten~ile ~tre~gth (cN/tex) 196 203 201 207 Modulus (N/tex) 60.3 60.2 59.1 58~,5 ~longation at break (%) 3.5 3.6 3.6 3.8 20 Exam~,le.~ 9-12: :
A $iber tow o ar~mid I of overall linear density 1680 dtex i~ stored f or 24 hour~ in sodium hydroxide ~olution :
of variou~ pH value~ at 60C. The "cen~,ile 6trength3, ~moduli and elongation~ at break of th2 ~"pecimane a""'cer !25 storage are 6hown ~n Table 3. ~xample 9 ~hows the value~
~~or th- ~tr-at~d ~lbor.
: ~
,, , . . ,, ,, . ~ . . . . .
~ 3 ~ ~ ~
Table 3:
Example No. 9 10 11 12 pH - 10 12 14 Tensile ~trength (sN/tex) 204 207 229 231 5 Modulus (N/tex) 60.3 60.4 61.2 61.4 Elongation at break (~) 3.4 3.5 3.9 3.9 ExamPle~ 13-16:
A fiber tow of aramid II of overall linear density 1100 dtex is stored for 24 hour~ in ~odium hydroxide solution of variou~ pH values at 60C. The ten~ile ~trength~, moduli and elon~ations at break of the ~pecimen~ aftar ~torage are shown in Table 4. Example 13 show3 the values for the untreated iibe~.
, .
Table 4:
15 Example No. 13 14 15 16 pH - 10 12 14 :
T2nsile ~trength (cN/tex) 225 228 230 231 :.
Modulu~ (N/tex) 47.4 46 47 46 Elongation at break (%) 4.6 4.8 4.8 4.9 20 Example~ 17-20: .
A ~iber tow of aramid I of overall linear denaity 1100 dtex is ~tored for 24 hour~ in ce~ent f~ltrate o~ p~ 12.5 at variou~ t~mperatures. The tensile ~trangth~, ~oduli and elongation~ at brea~ o~ tha epo~imena a~ter ~torage are ~hown in Table 5. Exa~ple 17 shows the ~alues for the untreated iber.
?~113310 ~ ::
Table 5:
Example No. 17 18 19 20 Storage t~mperature (C) - 22 60 95 Tensile Gtrength (cN/te~) 196 206 213 211 Modulus (N/tex) 60.3 59.9 59-3 57.0 Elongation at break (%) 3.5 3.6 3.7 3.9 Examples 21-24:
A fiber tow of aramid II of overall linear den~ity 1100 dtex is stored for 24 hours in cament filtrate of pH 12.5 at ~arious temperaturee. The tensile ~trengths, moduli and elongation~ at break of the specimen~ after ~torage are ~hown in Table 6. Example 21 shows the value~ for the untreated fiber.
. .
. , Table 6:
15 Example No. 21 22 23 24 Storage temperature (C) - 22 60 95 Tensile strength (cN/tex) 225 230 229 225 Modulus (N/tex) 47.4 45.6 45.7 45.2 ~ ~
Elongation at break (~) 4.6 4.9 4.8 4.8 ~ -:, ~ .
Examples 25-35~
", ~.,, ',"
A fiber tow of aramid I of overal linear den~ity 1680 dtex i~ ~tored for a relatively long period of time in cement filtrate of pH 12.5 at 80C. Fiber ~po~lmen~ are ;~
taken f rom time to ti~e and their ~echanical properties are determined. The t2n8ile strength~, moduli and elongatione at break of th0 ~pecimens stored for ~arious period~ of time are shown in Table 7.
':
~.
~ hr~ ~ 1 3 3 1 0 .. .
Table 7:
Example no. 25 26 27 28 29 30 31 32 33 34 35 Storage time 0 1 2 3 4 5 9 15 20 26 30 (days) 5 Tensile 210 214 221 227 230 227 228 227 228 228 232 strength (cN/tex) Modul us 60.3 58.5 59 58.2 58.2 58.0 58.6 59.0 58.0 58.2 59.3(N/tex) 10 Elongation 3.4 3.8 3.9 4.0 4.0 4.0 4.0 3.9 4.0 4.0 4.0 at break (X) Examplee 36-46:
. .
A fiber tow of aramid I of overall linear den~ity 1100 dtex ~ stored for a relatively long period of time in cement filtrate of pH 12.5 at 80C. Fiber specimens are taken from time to time and their mechanical properties are determined. The tensile otrengths, moduli and elon-gation~ at break o4 the specimens ~tored for variou~
perioda of time are shown in Table 8.
Table 8~
Example no. 36 37 38 39 40 41 42 43 44 45 46 Storage tlme 0 1 2 3 4 5 9 15 20 26 30 (days) Tensile 201 209 211 206 211 212 212 210 209 212 213 strength (cN/tex) Modulus 60 58.0 57.0 58.0 58 58.8 59.3 57.4 57.9 58.1 58.2 (N/tex) Elongation 3.5 3.7 3.9 3.7 3.8 3.8 3.7 3.8 3.8 3.8 3.8 at break (X) 3xamples 47-57:
I A fiber tow of aramid II of overall linear den~ity 1100 dtex i~ etored ~or a relatively long period of tlme in cement filtrate of pH 12.5 at 80C. Fiber ~pe~iimena are taken 4rom time to time and their me~ihaniaal propertie~
are determined. The tensile 3trength~, moduli and elongatione at break of the ~pecim~ns ~tored for variou~
periods of time are ahown in Table 9.
3 1 ~
Table 9:
Example no. 47 4B 49 50 51 52 53 54 55 56 57 Storage time 0 1 2 3 4 5 9 15 20 26 30 (days) Tensile 212 220 215 214 218 215 225 221 217 225 221 :
strength (cN/tex) Modul lls 45 .1 45 . 0 44 . 0 45 . 0 44 . 0 44 .1 45 . 2 45 . 8 44 . 7 45 .1 44 . 2 (N/tex) 10 Elongatlon 4.7 4.5 4.7 4.5 4.7 4.7 4.8 4.6 4.7 4.8 4.7 at break (%) Exam~les 58-65:
Multifilament~ which comprise an aramid ba~ed on 100 mol%
of terephthalic acid, 50 mol% of para-phenylenediamine and 50 mol% of 3,4'-diaminodiphenyl ether were employed in the following exa~ple~
The multifila~ent ia a fiber tow wet-spun and after~
treated by the customary pro~ee~. Storage wan carried out in cement filtrate: Portland Cement PZ 35 (200 g in 1 1 20 of water). ~; .
~ ' ~ '.:~`.' '` .'.'' Example~ 58-61 A fiber tow o$ f~lament~ of the aramid characterized :~
above o o~erall linear den~ity 1700 dtex wa etored for 24 hour~ in ~ement ~ilt~ate o~ pH 12.5 at variou~
tamperatures. The ten~ile ~trength~, moduli and elongation~ at brsak o~ the ~pe~imen~ after storage are ahown in the ~ollowing table. ~xample 58 sho~3 ~he ~alue~
for the untreated ~iber.
:
- ~ f~ 3 3 ~
. - 16 -Example No. 58 59 60 61 Storage temperature (C) - 22 60 95 Ten~ile ~trength (cN/tex) 225 225 235 240 Modulu~ (N~tex) 60 60 60 60 5 Elongation at break (~) 4 4 4 4 Exam~le~ 62-65: .
";
A ~iber tow of filaments o~ the aramid charaaterized above o~ overall linear den~ity 1700 dtex was ~tored for 24 hours in ~odium hydro~ide solution of various pH
10 values at 60C. The tensile ~trengths, moduli and ~ ::
elongation~ at break of the specimen~ after storage are Ehown in the following table. Example 62 ehow~ the value~
~or the untreated fiber.
Example No. 62 63 64 65 15 pH - 10 12 14 Ten~ile strength (~N/tex) 225 230 245 245 Modulus (N/tex) 60 60 60 60 Elongation at break (~) 4 4 4 4 - ~-
Claims (16)
1. A process for maintaining or increasing the tensile strength of fibers of aromatic copolyamides which are built up chiefly from para-monomers and are soluble in orgainc aprotic and polar solvents in the course of storage in alkaline media, comprising the measures:
a) production of fibers from the said aromatic copolyamides by dry or wet spinning processes which are customary per se, b) after-treatment of the resulting fibers in a manner which is known per se, and c) storage of the fibers in an aqueous environment which has a pH of at least 10 for at least a period of time and at a temperature such that the tensile strength of the said fibers, based on the tensile strength of the fibers employed in step c), is at least retained or increased.
a) production of fibers from the said aromatic copolyamides by dry or wet spinning processes which are customary per se, b) after-treatment of the resulting fibers in a manner which is known per se, and c) storage of the fibers in an aqueous environment which has a pH of at least 10 for at least a period of time and at a temperature such that the tensile strength of the said fibers, based on the tensile strength of the fibers employed in step c), is at least retained or increased.
2. The process as claimed in claim 1, wherein the storage of the fibers in step c) is carried out at least for a period of time and at a temperature such that the tensile strength of the said fibers, based on the tensile strength of the fibers employed in step c), is increased by at least 1%, in particular by 2 to 10%.
3. The process as claimed in claim 1, wherein fibers which have an initial tensile strength of at least 120 cN/tex and an initial elasticity modulus, based on 100% elongation, of more than 30 N/tex, are employed in step c).
4. The process as claimed in claim 1, wherein the strongly alkaline environment has a pH equal to or greater than 12, preferably 12 to 14.
5. The process as claimed in claim 4, wherein an aqueous solution of an alkali metal hydroxide, in particular sodium hydroxide solution, or an aqueous slurry or mixture of a hydraulically setting inorganic material, in particular concrete or cement, is used as the storage medium.
6. The process as claimed in claim 5, wherein an aqueous mixture of a hydraulically setting inorganic material is used as the storage medium and storage is carried out after mixing in of the fibers and after shaping of the resulting mixture.
7. The process as claimed in claim 1, wherein the storage is carried out at a temperature of 20 to 100°C, in particular at 20 to 60°C.
8. The process as claimed in claim 1, wherein an aro-matic copolyamide is employed which has an intrinsic viscosity of at least 2.4 dl/g (measured on solutions of 0.5 g of polyamide in 100 ml of 98%
strength by weight sulfuric acid at 25°C) and con-tain at least the recurring structural units of the formulae I, II and II
(I) (II) (III) in which -Ar- and -Ar'- are divalent organic radi-cals in which the valency bonds are in the para-position or a comparable coaxial or parallel posi-tion relative to one another, R is a C1-C4-alkyl radical, in particular methyl, a C1-C4-alkoxy radical, in particular methoxy, or a chlorine atom, R' is an unsubstituted or alkyl-substituted methyl-ene radical or a grouping -O-Ar-O-, in which -Ar- assumes the meaning defined above, and the proportions of the recurring struc-tural units I, II and III, based on the total amount of these structural units in the polymer, lie within a range defined by the following corner points:
point Q corresponding to 5 mol% of structural units of the formula I, 45 mol% of structural units of the formula II and 50 mol% of the structural units of the formula III, point R corresponding to 45 mol% of structural units of the formula I, 5 mol% of structural units of the formula II and 50 mol% of structural units of the formula III, point S corresponding to 60 mol% of structural units of the formula I, 35 mol% of structural units of the formula II and 5 mol% of structural units of the formula III, point T corresponding to 20 mol% of structural units of the formula I, 75 mol% of structural units of the formula II and 5 mol% of structural units of the formula III, and point U corresponding to 5 mol% of structural units of the formula I, 80 mol% of structural units of the formula II and 15 mol% of structural units of the formula III.
strength by weight sulfuric acid at 25°C) and con-tain at least the recurring structural units of the formulae I, II and II
(I) (II) (III) in which -Ar- and -Ar'- are divalent organic radi-cals in which the valency bonds are in the para-position or a comparable coaxial or parallel posi-tion relative to one another, R is a C1-C4-alkyl radical, in particular methyl, a C1-C4-alkoxy radical, in particular methoxy, or a chlorine atom, R' is an unsubstituted or alkyl-substituted methyl-ene radical or a grouping -O-Ar-O-, in which -Ar- assumes the meaning defined above, and the proportions of the recurring struc-tural units I, II and III, based on the total amount of these structural units in the polymer, lie within a range defined by the following corner points:
point Q corresponding to 5 mol% of structural units of the formula I, 45 mol% of structural units of the formula II and 50 mol% of the structural units of the formula III, point R corresponding to 45 mol% of structural units of the formula I, 5 mol% of structural units of the formula II and 50 mol% of structural units of the formula III, point S corresponding to 60 mol% of structural units of the formula I, 35 mol% of structural units of the formula II and 5 mol% of structural units of the formula III, point T corresponding to 20 mol% of structural units of the formula I, 75 mol% of structural units of the formula II and 5 mol% of structural units of the formula III, and point U corresponding to 5 mol% of structural units of the formula I, 80 mol% of structural units of the formula II and 15 mol% of structural units of the formula III.
9. The process as claimed in claim 8, wherein -Ar- and -Ar'- axe 1,4-phenylene, R is methoxy or chlorine or, in particular, methyl and R' is -0-1,4-phenylene-O-, the proportions of the amounts of the recurring structural units, based on the total amount of these structural units within the polymer, lying within the following ranges:
recurring structural unit of the formula I: 15 to 45 mol%, recurring structural unit of the formula II: 20 to 70 mol%, and recurring structural unit of the formula III: 15 to 50 mol%.
recurring structural unit of the formula I: 15 to 45 mol%, recurring structural unit of the formula II: 20 to 70 mol%, and recurring structural unit of the formula III: 15 to 50 mol%.
10. The process as claimed in claim 1, wherein the aromatic copolyamide employed is a compound which has an intrinsic viscosity of 2.4 to 6.5 dl/g (measured on solutions of 0.5 g of polyamide in 100 ml of 98% strength by weight sulfuric acid at 25°C) and contains at least the recurring structural units of the formulae I, IV and V
(-OC-Ar-CO-NH-Ar'-NH-) (I) (IV) (V) in which -Ar- and -Ar'- have the meanings defined in claim 8, and the proportions of the recurring struc-tural units I, IV and V, based on the total amount of these structural units in the polymer, lie within the following ranges:
recurring structural unit of the formula I: 40 to 65 mol%, recurring structural unit of the formula IV: 5 to 55 mol%, and recurring structural unit of the formula V: 5 to 35 mol%.
(-OC-Ar-CO-NH-Ar'-NH-) (I) (IV) (V) in which -Ar- and -Ar'- have the meanings defined in claim 8, and the proportions of the recurring struc-tural units I, IV and V, based on the total amount of these structural units in the polymer, lie within the following ranges:
recurring structural unit of the formula I: 40 to 65 mol%, recurring structural unit of the formula IV: 5 to 55 mol%, and recurring structural unit of the formula V: 5 to 35 mol%.
11. The process as claimed in claim 10, wherein -Ar- and -Ar'- are 1,4-phenylene, and wherein the proportions of the amounts of the recurring structural units, based on the total amount of these structural units within the polymer, lie within the following ranges:
recurring structural unit of the formula I: 45 to 55 mol%, recurring structural unit of the formula IV: 35 to 45 mol%, and recurring structural unit of the formula V: 5 to 25 mol%.
recurring structural unit of the formula I: 45 to 55 mol%, recurring structural unit of the formula IV: 35 to 45 mol%, and recurring structural unit of the formula V: 5 to 25 mol%.
12. The process as claimed in claim 1, wherein an aro-matic copolyamide is employed which has an intrinsic viscosity of at least 2.4 dl/g (measured on solutions of 0.5 g of polyamide in 100 ml of 98%
strength by weight sulfuric acid at 25°C) and con-tains at least the recurring structural units of the formula I and VI
(OC-Ar-CO-NH-Ar'-NH-) (I) and (VI) in which Ar and Ar' have the meanings defined in claim 8 and the proportions of the recurring struc-tural unite I and VI, based on the total amount of these structural units in the polymeres, lie within the following ranges:
formula I: 50 to 60 mol%; formula VI: 40 to 50 mol%.
strength by weight sulfuric acid at 25°C) and con-tains at least the recurring structural units of the formula I and VI
(OC-Ar-CO-NH-Ar'-NH-) (I) and (VI) in which Ar and Ar' have the meanings defined in claim 8 and the proportions of the recurring struc-tural unite I and VI, based on the total amount of these structural units in the polymeres, lie within the following ranges:
formula I: 50 to 60 mol%; formula VI: 40 to 50 mol%.
13. A shaped article obtainable by the process as claimed in claim 6.
14. The shaped article as claimed in claim 13, which contains multifilaments, preferably multifilaments having an overall linear density of 840 to 18,000 dtex.
15. The shaped article as claimed in claim 13, which contains staple fibers.
16. The use of the fibers treated or to be treated by the process as claimed in claim 1 for the production of gypsum, cement, mortars, plasters, screed or con-crete.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP4300626.4 | 1993-01-13 | ||
| DE4300626A DE4300626C2 (en) | 1993-01-13 | 1993-01-13 | Process for maintaining or improving the mechanical properties of fibers from aromatic copolyamides in alkaline media and use of the treated fibers for the production of moldings |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2113310A1 true CA2113310A1 (en) | 1994-07-14 |
Family
ID=6478060
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2113310 Abandoned CA2113310A1 (en) | 1993-01-13 | 1994-01-12 | Process for maintaining or improving the mechanical properties of fibers of aromatic copolyamides in alkaline media and shaped articles containing such fibers |
Country Status (9)
| Country | Link |
|---|---|
| US (1) | US5616683A (en) |
| EP (1) | EP0606859B1 (en) |
| JP (1) | JPH06280115A (en) |
| AT (1) | ATE164894T1 (en) |
| BR (1) | BR9400083A (en) |
| CA (1) | CA2113310A1 (en) |
| DE (2) | DE4300626C2 (en) |
| FI (1) | FI940123A (en) |
| NO (1) | NO940114L (en) |
Families Citing this family (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4401233A1 (en) * | 1994-01-18 | 1995-07-20 | Hoechst Ag | Bundles of staple fibers made from aromatic polyamides with improved dispersibility in viscous matrices, and process for producing fiber-reinforced composites |
| US6001476A (en) * | 1997-04-18 | 1999-12-14 | Selivansky; Dror | Method of upgrading existing nylon fibers and use of same for reinforcement of cementitious composites |
| DE10159339B4 (en) * | 2000-12-05 | 2004-04-08 | Akzo Nobel N.V. | Filler and use of such a filler |
| DE10159337B4 (en) * | 2000-12-05 | 2004-04-08 | Akzo Nobel N.V. | Filler and use of such a filler |
| US7669236B2 (en) * | 2004-11-18 | 2010-02-23 | Biogy, Inc. | Determining whether to grant access to a passcode protected system |
| US7770018B2 (en) * | 2004-11-18 | 2010-08-03 | Biogy, Inc. | Setting up a security access system |
| US7979716B2 (en) | 2004-11-18 | 2011-07-12 | Biogy, Inc. | Method of generating access keys |
| US7707622B2 (en) | 2004-11-18 | 2010-04-27 | Biogy, Inc. | API for a system having a passcode authenticator |
| US20060107312A1 (en) * | 2004-11-18 | 2006-05-18 | Michael Fiske | System for handing requests for access to a passcode protected entity |
| US7565548B2 (en) * | 2004-11-18 | 2009-07-21 | Biogy, Inc. | Biometric print quality assurance |
| US20060107315A1 (en) * | 2004-11-18 | 2006-05-18 | Michael Fiske | System that uses access keys |
| US8209751B2 (en) * | 2004-11-18 | 2012-06-26 | Biogy, Inc. | Receiving an access key |
| US20090228714A1 (en) * | 2004-11-18 | 2009-09-10 | Biogy, Inc. | Secure mobile device with online vault |
| US7702911B2 (en) * | 2004-11-18 | 2010-04-20 | Biogy, Inc. | Interfacing with a system that includes a passcode authenticator |
| US20060107309A1 (en) * | 2004-11-18 | 2006-05-18 | Michael Fiske | Using an access key |
| US7886155B2 (en) | 2004-12-20 | 2011-02-08 | Biogy, Inc. | System for generating requests to a passcode protected entity |
| US20080288786A1 (en) * | 2004-12-20 | 2008-11-20 | Michael Stephen Fiske | System with access keys |
| EP2661457B1 (en) * | 2011-01-04 | 2018-03-28 | Teijin Aramid B.V. | Electrical insulating paper |
| KR101386429B1 (en) * | 2012-12-28 | 2014-04-29 | 코오롱인더스트리 주식회사 | Method of dry-spinning para-aramid fiber |
| WO2016170050A1 (en) * | 2015-04-22 | 2016-10-27 | Teijin Aramid B.V. | Cord comprising multifilament para-aramid yarn comprising non-round filaments |
Family Cites Families (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL53915C (en) * | 1938-10-03 | |||
| US2781242A (en) * | 1954-02-05 | 1957-02-12 | Du Pont | Process of improving the hand of polyethylene terephthalate fabric by heat shrinking and hydrolyzing the fabric |
| NL212981A (en) * | 1956-12-14 | |||
| JPS53138422A (en) * | 1977-05-11 | 1978-12-02 | Asahi Chemical Ind | Formed product of fiberrreinforced cement |
| JPS58151363A (en) * | 1982-03-01 | 1983-09-08 | 帝人株式会社 | Fiber reinforced cement product |
| JPS61183155A (en) * | 1985-02-09 | 1986-08-15 | 鹿島建設株式会社 | Manufacture of fiber reinforced cement concrete products |
| EP0199090B1 (en) * | 1985-03-23 | 1990-10-03 | Hoechst Aktiengesellschaft | Shaped articles of aromatic copolyamides, and process for their manufacture |
| EP0225404B1 (en) * | 1985-11-28 | 1991-04-10 | Mitsui Kensetsu Kabushiki Kaisha | Fibre-reinforced moulded cement body |
| US4693749A (en) * | 1985-12-20 | 1987-09-15 | E. I. Dupont De Nemours And Company | Cement reinforcement |
| US5306782A (en) * | 1989-05-08 | 1994-04-26 | American Cyanamid Company | Surface-modified polyacrylonitrile fibrous substrates |
| US4974522A (en) * | 1989-06-09 | 1990-12-04 | Relmech Manufacturing Limited | Cold-molded cementitious composites reinforced with surface-modified polyamide fibres and method of preparing same |
| DE3929376C1 (en) * | 1989-09-05 | 1991-04-18 | E.I. Du Pont De Nemours And Co., Wilmington, Del., Us | |
| DE4010941A1 (en) * | 1990-04-05 | 1991-10-10 | Hoechst Ag | METHOD FOR PRODUCING AROMATIC POPYAMIDES WITH HIGH HYDROLYSIS RESISTANCE |
| ATE140708T1 (en) * | 1991-02-14 | 1996-08-15 | Hoechst Ag | AROMATIC COPOLYAMIDES, METHOD FOR THE PRODUCTION THEREOF AND STRUCTURES FORMED THEREFROM |
| US5266672A (en) * | 1991-07-02 | 1993-11-30 | Hoechst Aktiengesellschaft | Aromatic copolyaide from diamino benzanilide |
| DE4139747A1 (en) * | 1991-12-03 | 1993-06-09 | Bayer Ag, 5090 Leverkusen, De | FUEL-BASED, OPTICALLY ACTIVE PEARL POLYMERISES |
| CZ134893A3 (en) * | 1992-07-08 | 1994-02-16 | Hoechst Ag | Aromatic copolyamides, process of their preparation and objects made therefrom |
-
1993
- 1993-01-13 DE DE4300626A patent/DE4300626C2/en not_active Expired - Fee Related
-
1994
- 1994-01-07 EP EP19940100194 patent/EP0606859B1/en not_active Expired - Lifetime
- 1994-01-07 AT AT94100194T patent/ATE164894T1/en not_active IP Right Cessation
- 1994-01-07 DE DE59405607T patent/DE59405607D1/en not_active Expired - Fee Related
- 1994-01-11 FI FI940123A patent/FI940123A/en unknown
- 1994-01-12 CA CA 2113310 patent/CA2113310A1/en not_active Abandoned
- 1994-01-12 NO NO940114A patent/NO940114L/en unknown
- 1994-01-12 BR BR9400083A patent/BR9400083A/en not_active Application Discontinuation
- 1994-01-13 JP JP206294A patent/JPH06280115A/en active Pending
- 1994-01-13 US US08/181,172 patent/US5616683A/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| EP0606859A1 (en) | 1994-07-20 |
| NO940114L (en) | 1994-07-14 |
| ATE164894T1 (en) | 1998-04-15 |
| DE59405607D1 (en) | 1998-05-14 |
| EP0606859B1 (en) | 1998-04-08 |
| JPH06280115A (en) | 1994-10-04 |
| BR9400083A (en) | 1994-08-02 |
| US5616683A (en) | 1997-04-01 |
| FI940123A0 (en) | 1994-01-11 |
| DE4300626C2 (en) | 1996-11-14 |
| NO940114D0 (en) | 1994-01-12 |
| DE4300626A1 (en) | 1994-07-14 |
| FI940123A (en) | 1994-07-14 |
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