CA1326413C - Process for coating polymer surfaces and coated products produced using such process - Google Patents

Abstract

ABSTRACT
Processes for treating polymeric surfaces to pro-duce smooth, durable, slippery coatings which are able to withstand the rigors of sterilization and, long term expo-sure to human blood and other bodily fluids without substantial loss of their slipperiness. An article or device suitable as a wound drainage device coated in accordance with the process described is also disclosed.

Description

1326~13 BM 8984~A-CIP

PROCBSS FOR COATING POLYMER SURFACES
AND COATED PRODUCTS PRODUCED VSING SUCH PROCESS
FIELD OF THE INV~IO~
This invention relates to the field of coatingc for polymer 6urfaces and particularly to proces~es for treating polymeric surfaces to produce smooth, durable, slippery coatings which are able to withstand the rigors of sterilization and long term exposure to human blood and other body fluid~ without substantial loss of their slipperiness. Nore particularly this invention relates to a proces~ for coating surgical devices made of various polymeric material~ to provide a superior ~mooth, durable slippery coating thereon.
BACKG~OUND OF THE INVENTION

The use of devices made from various polymeric materials, including silicone rubber and polyvinyl chloride ~PVC) and the like, has ach~eved an import~nt pl~ce in carrying out numerous surgical procedures. An important olass of ~uch devicQs consists o~ various wound drainage device~, surgical inserts and ~urgical tubing all of which are important in the rQmoval of blood and other ~luids from a surgical or wound sits.
Generally speaking in the cour~e o~ 6uch proce-dure~ a tubular device made of ~ome inert, usually polymeric material, ~ust be inserted And positioned through body tis-sue and mu~t allow unrestricted flow of blood through the device for up to sever~l days. The presently ~vallable de-vicas, ~pecially those made of ~llicone, have undesirably hlgh rQsistance to movement through tissue. A greater , ~326~13 problem is an undesirably high l~vel of blood clot formation inside drainage tubes, e~pecially those made from silicone and PVC. Most ~erious of all, the clots which form, especially in ~ilicone, are difficult to remove. I'hese undesirable characteristics primarily derive from the ~act that silicone rubber tubing has a very~ hydrophobic surface which is very poorly wetted by aqueou~ media. Devices made from PVC, although better performing than siliaone, also have poorly wetted, nonslippery suraces.
Thus it has been deemed desirable to develop a process which would allow one to coat the surfaces of devices made from various polymeric materials, such as for example silicone, PVC, latex, polyester, polyurethane, and thermopla~tic elastomers, to improve the wettability and slipperine6s of such devices, particularly under conditions encountered when such devices are employed in wound drainage applications.
Amongst the prior art in which the applicants are aware dealing with the problem of coating various polymeric materials in contact with human body fluids are the follow-ing:
U.S. Patent No. 4,100,309 discloses a multistep method of applying a hydrophilic coating on a substrate.
U.S. Patent No. 4,119,094 is related to U.S.
Patent No. 4,100,309 and claims arti¢les coated in accor-dance with the process ~et out therein.
U.S. Patent No. 3,925,178 discloses a process for treating a plastic contact lens to make the lens surface hydrophilic without changing the optical characteristics of the lens.
U.S. Patent No. 4,312,575, al~o disclos~ contact lenses having an ultrathin, clear, lipid-permeable hy-~32~3 drophilic barrier coating which is formed by an electricalglow discharge process.
U.S. Patent No. 4,589,879 teache~ a method ~or coating vinyl tubing with PVP using DMF as a solvent. The coated product produced i~ however ~ound to be distorted and the coating uneven and of very poor quality.
None of the foregoing references teaches the pro-cess or the pxoducts produced thereby which are the subject of the present invention.

SUMMARY OF THE INVENTION

The present invention is directed to a process for treating polymeric surfaces to produce smooth durable slip-pery coatings which are particularly suited for use as wound drainage or other surgical devices. Products made from such coated polymeric materials are al60 taught herein.

~escription of the Invention It has been found that producing a hydrogel sur-face on a silicone, PVC, latex, polyestQr, polyurethane, or thermoplastic ela~tomer surface, that i~, one which iR
wettable and slippery in water, will sub~tantially improve the performance of wound drainage devices con~tructed from ~ilicone rubber and PVC. For example, the frictional forces produced on the surface~ of such devices by inserting or removing them through tissue will be greatly reduced. More importantly the tendenay for the blood to clot has been shown to be lQssened and the ease o~ clot removal is greatly enhanced by such a coated ~urface. It is generally rscognized that a fluorinated surface (i.e. Teflon or Teflon-like) is much less prone to blood clot formation 1 32~413 (i.e. is less thrombogenic) than a ~ilicone rubber or PVC
surface, probably becau~e it has a lower energy sur~ace, and a lower coefficient of friation. Hence, low energy fluorinated sur~aces are also expected to produce surfaces with lesser blood clotting tendencie~ and less adherence of blood clots if they do form.
The object of the present invention is a process or treatment which will provide improved surface properties to wound or surgical drainage devices made from various polymeric materials, including silicone, PVc, latex, polyester, polyurethane and thermoplastic elastomers. The improved surface properties to be achieved will cQnsist of either a more wettable, slippery surface, or a lower energy, less thrombogenic surface. These characteristics are to be provided, respectively, via physically or chemically an-chored hydrogel polymer coatings, or by a fluorinated or polyfluorocarbon coated silicone rubber and PVc surface.
The modified polymeric surface must meet four conditions or criteria to be successful.
The criteria, or ~peci~ications, for an acceptably treated (coated) wound drainage device are the following:
1. The modified surface must retain this charac-teristic for a minimum of 100 hours when in contact with wound secretions.

2. The process and/or condition which produces such a surface must be applicable to the inside and outside diameters of round tubes and ir-regular cross-sectional shaped tubes. These round tubes and/or combinations of lrregular shapes are known as closed wound drainage devices, usually used in combination with a 132~413 suction device: ~uch as Snyder Hemovac~ or surgivac~.

3. The modified surface must be able to withstand an ethylene oxide sterilization process and not deteriorate, crack, have an adversely a~ected shelf-life, or impair the physical charac-teristics or properties of the polymeric sub~trate layer or 6urface.

4. The proces8 and/or condition which produces such a surface must be ~afe (e.g., FDA
approvable, pass USP XIX class IV), reasonable and feasible to scale-up in a continuous, semi-continuou~ or batch manufacturing mode.
It should be understood that thers are significant di~ferences for example between silicone rubber (crosslinked polydimethy~iloxane) and flexible vinyl (PVC). The basic polymer ~tructures are as follows:

~ilicone PVC

However, the silicone as use~ is a filled (silica), cross-linked (i.e., three dimensional, insoluble network) rubber, while the PVC i8 a soluble thermoplastic containing a 801-vent leachable plasticizer and no filler. The ~ilicone is a relatively stable, low surface energy (highly nonwater-wettable) material while PVC has an inter~ediate ~urface energy and water wettability and i8 relatively su~ceptible to reaction due to the chlorine-carbon bonds (108g of HC~

via heat or strong base, pos~ible quarternization with amines). However, the silicone has some residual ahemically reactive silane (SiH) and/or vinyl ~SiCH-CH2) group~. These were the groups used to curs (cross-link) the rubber. They are potentially usable for chemical attachment (grafting), if they are present in sufficient concentration, on or near the tubing surface. ~he ~ilica filler in the ~ilicone also possesses reactive surface silanol (SioH) groups usable for grafting, again if a sufficient concentration of these groups is at or just below the rubber surface, to provide a useful degree of bonding.
A complication with PVC is the presence of the organic ester (e.g. dioctyl phthalate) plasticizer, which can both migrate (bloom) to the surface and interfere with surface reactions, or be leached out during solution or solvent treatment, resulting in a hardened, perhaps more brittle or crack-prone surface.
However, it must be remembered that vinyl tubing is not cros~-linked and any organic liquid which i~ a sol-vent for PVC will attack or erode the tu~ing. Thi~ is in contrast to the silicone tubing, which is cross-linked and swells but cannot dissolve in a liquid which is a ~olvent for uncross-linked sili¢one. Hence sllicone rubber can be easily and conveniently impregnated with a number of poten-tial coupling or grafting agents, using a range of solvents and soaking conditions, while solvenk solutions ~or treating vinyl must ~e chosen and used with care.
Hence, although soma coating or treating methods can be used on both silicone, PVC and other polymeric mate-rials, the special requirements of the substrates' surfaces must bQ kept in mind and the procedures adapted to the sur-132~13 "

faces as required; some possible treatment procedures willbe unique to the particular surface utilized.
A chemical process ha~ been developed far coating drainage tubes with a hydrophilio polymer that substantially reduces the coefficient of friction and 6urface tension of these drain materials. The coating provides an extremely soft, slippery outer surface which enhances ease o~ instal-lation and removal, while minimi~ing frictional irritation of surrounding cells and ti6sue. The internal coating provides a surface with a low interfacial tension 6ubstan-tially reducing intraluminal and fenestration port adhesion of blood, blood clots, or other exudate, thus decreasing the negative pressure required to evacuate the wound and increasing the rate of flow through the drain.
The coating process of the present invention pro-vide~ a chemical bond between the polymeric drain materials and a polyvinvlpyrrolidone hydrogel, treated with a silane and copolymer to provide a highly biocompatible coating while maintaining clarity, radiopacity, and other physical properties of the drains.
The coating material i8 a hydrogel. A hydrogel is a polymeric material which exhibits the ability to swell in water and retain a significant fraction (e.g., 20%) of water within its structure~ but which will not dlssolve in water. Hydrogels have been shown to have great potential as blood and tissue compatible materials.
In theory, hydrogels are attractive as bioma-terials because they are similar to the body' 8 own highly hydrated composition. Thus, if the interface of a foreign ob~ect does not appear foreign to the biomoleculQs and cells in the vicinity, then they should not be attracted to the interface.

" ~32~413 In keeping with the foregolng considerations a treatment procedure has been developed that gives a more slippery surface than untreated control~ for various poly-meric materials which comprises the following general ~tep~:
In the case of a silicone, latex, polyester, polyurethane or thermoplastic elastomer polymeric ~urfaces:
- Application of a tie coat compri~ing a solution of a poly(methyl vinyl ether/maleic anhydride) such as AN
119, AN 139, AN 149, Gantrez AN-169 or AN-179 (GAF Corp.) in a 1:1 methanol/isopropanol; followed by a heat-dry cycle, then, - Application of a slippery coating comprising a combined solution of polyvinyl pyrrolidone (PVP), K-90 (GAF
Corp.) and N-trimethoxypropyl 8ilyl polyethylenimine (PSo76-Petrarch) in isopropanol; followed by a further heat dry cycle.
In the case of a polyvinylchloride polymeric sur-face:
- Application of a slippery coating comprising a combined solution of polyvinyl pyrrolidone (PVP), K-90 (GAF
Corp.) and N-trimethoxypropyl silyl polyethylenimine (PS076-Petrarch) in n-propyl alcohol, followed by a heat dry cycle in an air-circulating oven at 80C for about 20 minutes.
Generally, for silicone polymer appliaations the article will first be treated with 1:1 solution of methanol and isopropanol containing from about 0.25-4.0 wt.% of a polymethyl-vinyl ether/malelc anhydride, such Gantrez as AN-169 (GAF Corp.) or the like. Preferably about 1 wt% Gantrez AN-169 ln a methanol/isopropanol solution will be used.
However, any solvent can be utilized with equal effect, which solubilize~ the Grantez and permits it to adhere to the surface of the silicone.

``` 1326~13 It has been found that a 50/50 methanol/isopropanol (IPA) mixture swells the silicone rubber two to three times as much as methanol alone, while isopropanol swells it even more. The degree of swell in the priming step for treating silicone is very important in obtaining the durable, slippery when wet, coating of PVP/PS076. The Gantrez ANi69 hal~ e~ter is probably impregnated into the silicone surface if the degree of swelling is _1.5 percent. Consequently isopropanol alone is expected to work especially well a6 the Gantrez impregnating solvent.
In any event these swelling data, see Table 1, strongly suggest that ~ome degree of swelling iB needed to achieve a good result from the two step coating procedure on silicone.

--~ 1 326413 TABI,E 1., 8WELLING OF ~ILICONE TUBIN~I IN LpWER
AI,CO}IOL~ AND AI.CO~OL MIXTURE~ ~ n ~eight Ga~n (Percent by We~ght) Versus Swellino Time ~n M~nutes Alcohol 10 Z0 60 180 360 4320 Methanol(b) 1.2 1.4 l.S 1.2 0.9 0.7 Ethanol(C) 2.1 3.2 4.3 4.8 4.6 4.1 n-Propanol(d) 3.9 5.4 7.7 12.78 -- 14.6 n-Butanol(e) 4.6 6.7 11.4 IS.~ 1~.5 17.9 n-Pentanol(f) 4.3 6.1 9.0 13.0 13.8 14.3 iso-Propanol(9) 5.6 8.0 13.5 19.3 21.6 22.1 1/1 Methangll Z.3 2.8 3.9 4.3 -- 3.5 n-Propanol~h~
1/1 Methanol/ 2.1 2.6 3.9 4.2 -- 3.3 ~so-Propanol(ll) (a) II~gh chem~cal purity, well dr~ed alcohols used at room temperature (70 F, Z3 C). All swell~ng experlments ln run tr~pl~cate and we~ght gain results averaged.
b ~urd~ck and Jackson d~stilled ~n glass, cO.OS percent water.
c Absolute ethanol, dr~ed over mol sleve 3A.
d Aldr1ch Gold Label (~0.005 percent water).
J. T. aaker Reagent grade (~0.05 percent water).
n-Pentanol, Metheson Coleman and Bell, 99~ mole percent pure.
a J. T. ~aker reagent grade, dr~ed over mol s~eve 3A.
~ 50/50 mixture by volume.

. .

1 3 ~ 3 - sased upon evaluations undertaken it has been determined that methanol alone i6 not nearly a6 ef~ective a solvent for treatment of silicone as the 50/50 methanol/isopropanol blend or IPA alone. Thi appears to be a function of degree of swelling.
Similar results are obtained with vinyl (PVc) tubing where only isopropanol (IPA) is used as solvent, except that some wettability is noted when methanol alone is used as the coating solvent. However, the use of the mixed alcohols or IPA alone as the solvent results in definitely better slipperiness. Also it is quite clear that PS076 must be used along with the PVP or the high~y slippery wettability is 108t much more quickly and readily.
It is believed that there is a ~ubsta~tial and important difference in the final slipperiness and its durability between the use of methanol alone and of 50/50 methanol/IPA or IPA alone as the solvent3, on both the silicone and vinyl substrates that is not anticipated in the prior art.
The heat-dry aycle following the initial treatment with the Gan~rez solution i~ accompli~hed by placing the treated article in an air-circulating oven at 80a for about 15 minutes.
The second step in the treatment process of the present invention for silicone polymer latex, polyester, polyurethane or thermoplastia elastomers invol~es the appli-cation of a combined solution of PVP and PS076, followed by a heat-dry cycle to form a slippery coating.
Generally speaking for silicone polymer products this solution will be a ~olution containing from about 0.25 to about 5.0 weight percent PYP and from about 0.1 to about 1.0 weight percent PS076 in pure isopropanol.

~32~13 Preferably, a solution containing about 2 wt.
percent PVP and about 0.2 wt percent PS076 will be utilized in pure isopropanol.
Generally speaking, for pol~vinyl chloride poly-meric products the combined ~olution o~ PVP and PSO76 will be applied to the article directly without any pretreatment.
The solution will generally contain from about 0.25 to about 5.0 weight percent of PVP and from about ~.1 to about 1.0 weight percent of PSO76 in pure isopropanol or n-propyl alcohol. Preferentially, about 2 weight percent PVP and about 0.2 weight percent PSO76 will be utilized in pure n-propyl alcohol.
Polyvinyl chloride (P'~C) tubing has been dried in ovens (circulating air) set at 150C, 200C and 250C. Both untreated vinyl and tubing freshly treated with IPA were tested. At 150C the tubing withstands about 5 minutes before showing sub~tantial evidence of softening and can be dried. However, at 200C all samples began to melt within 10-15 seconds and at 250C they melted almost immediately (5 seconds). It was impossible to dry vinyl tubing at these temperatures which are taught by the prior art.

A number of materials similar to PSO76 have been found to work with equal advantage. PSO76 alternate~ are listed in Table 2. These include PSO76.5, a closely related polymeric silane coupling agent and a number o~ other polymeria silane coupling agents. These are unique materials introduced by Petrarch. They are polymers with silane coupling functionality [-Si~oR)3]~ where R i8 methyl or ethyl groups, attached as pendent groups on the backbone.

There are al80 a number of the usual low molecular weight ~ilane coupling agents used in industry for a number of years. These are made commercially by Dow Corning, Union Carbide and others. Lists of these products are appended.
All coupling agents can self react, after hydrolysis (e.g., via moi~ture in air or condensed on a surface or added to a treatment procedure), through the intermediate t-Si(oH)3]
groups which form, or can form. Water is eliminated and siloxan2 (si-0-Si) crosslinks form. These SioH groups can also interaat with organic hydorxyl groups resulting in Si-0-C crosslinks. Yet these coupling agent group~ are thermally stable, ana chemically stable in the absence of water. Hence they can be mixed with PVP, or other water or alcohol or organic solvent soluble polymers in dry alcohol or other dry organic solvent solutions without reacting.
When the mixture~ are exposed to water, as in coating procedures in air, and especially if a water treatment or wash i8 used, the chemical reaction described above leading to either a) self-crosslinking of the silane coupling agent or b) crosslinking of the silane coupling agent and the organic polymer (if some hydroxyl group~ are available on the polymer), or c) both, can occur. If these types of reactions occur, more durable, wettable coating~ would be achieved -- provided an appropriate balance of material~ is maintained.

The polymeria ¢oupling agents are, in general, actually shown to be much more active in produaing gelled (i.e., crossllnked or cured) films (see Table 2) than the low molecular weight silane coupling agents. ~owever, the quaternary salt coupling agents, with long aliphatic ~fatty) groups attached also appear to be active. In addition, several other types of 6pecial polysiloxanes or silicone copolymers are shown to be potentially usable.

~ 32 ~13 TABLE 2. PS076 ALTERNATE5 -PVP
Item Product Curing No. Number Chemical Type Source Agent(a) Comments (b) 1 PS076 (N-Trimethoxy- Petrarch 3 Ethylene-silyl-propyl) Systems, imine/-polyethylene- Inc. silane imine coupling agent copolymer 2 A0700(c) N-2-Aminoethyl- ditto 2 Silane 3-aminopropyl coupling trimethoxy- agent,amino silane functional 3 Corcat Polyethylene- Virginia 2 Polyethyl-P-18 imine Chemicals eneimine (d) 4 PS076.5 (Dimethoxy- Petrarch 3 Ethylene-(e) silylpropyl)- Systems, imine/-polyethylene- Inc. silane imine coupling agent copolymer PS075(f) (N-Trimethoxy- ditto 5 Polyamide/-silylpropyl)- silane polyazamide coupling agent 6 PS078.5 (Triethyoxy- " 4 Poly-silyl modified butadiene/-poly(l,2- silane butadiene) coupling agent 7 PS074.2 Nethacrylate " 4 Complex functional polymeric polymeric silane silane coupling agent copolymer (1) 8 PS072(g) Dimethylsilox- " 4 Polysilox-ane ethylene ane-oxidepropylene hydrophilic oxide copolymer organic block copolymer 9 PS922 Glycidoxy- " 5 Epoxy-propylmethyl functional (45-55%) di- silicone methylsiloxane copolymer copolymer PS9120 Polydiethoxy- " 5 Polyorgano-(h) silane ~40-42~ ~ilicate SiO2 content) precursor of poly-silicic acid and hydrophilic silica 132~413 TABLE 2. (continued) -PVP
Item Product Curing No. Number Chemical Type Source Agent comments (a) (b) 11PS077 (N- " 4 Poly-Trimethoxysilyl ethylene -propyl)-O- glycol polyethylene urethane oxide urethane silane coupling agent 1209745 Octadecyl- " 4 Silane dimethyl [3- coupling (Trimethoxy- agent silyl)- quaternary propyl]ammonium ammonium chloride salt (i) 13T1803 N-Tetradecyldi " 4 ditto methyl (3-trimethoxy-silylpropyl) ammonium chloride 14G6720(k) (y-Glycidoxy- " 3 Silane propyl~trimeth- coupling yoxysilane agent epoxy functional . T2924 N- " 2 Silane Trimethoxysilyl coupling -propyltri-N- agent butyl ammonium quaternary bromide ammonium salt 16I7840 Isocyanato- " 3 Silane propyl- coupling triethoxysilane agent (95%) isocyante functional 17T2507 N-(Triethoxy- " 1 Silane silylpropyl) coupling urea agent urea functional 18D4520 Diethoxy- " 1 Silane phosphate-ethyl coupling triethoxysilane agent diethyl phosphate functional 19 Corfax Fatty al~yl Virignia 1 Dispersant/
712 substituted Chemicals surfactant polyethylene- (d) with imine reactive amines Footnotes on following page.

~32~
TABLE 2. (continued) (a) Approximately 0.2-0.4 percent of the test material added to 1 gram of a 2.0 percent PVP (K90) solution in isopropanol in 4 dram glass via].s and the solution or cloudy dispersion taken to dryness at 80 C (-2-3 hours), cooled, and 5 ml distilled water added. The samples were inspected and gently swirled by hand over a 8-hour period. The behaviour of the solid film was rated in one of five categories as follows:
1. Dissolved readily to a clear solution, over 1-2 hours 2. Dissolved slowly to a clear solution, over 2-4 hours 3. Formed a gel which swelled greatly, then slowly dispersed until it was difficult to see over 2-4 hours.
4. Formed a gel which swelled greatly, then slowly dispersed to a cloudy dispersion, over 2-4 hours.
5. Formed a slightly swollen gel which remained intact over 8 hours.
(b) General description identifies whether the material is polymeric in nature.
(c) Equivalent to Dow Corning Z-6020 and Union Carbide UC 1120.
(d) Division of Celanese Corp. (formerly Cordova Chemical Company).
(e) Modified version of PS076, with two reactive methoxysilyl groups per coupling agent unit, instead of three as in PS076 (f) Discontinued product formerly available from Petrarch.
(g) Three related products from Petrarch were not tested but would be expected to be equivalent. These are PS071, PS073, PS073.5, all dimethylsiloxane-ethylene oxide copolymers.
(h) Three related products from Petrarch were not tested but would be expected to be equivalent. These are PS912X, PS9130 and PS9150. The first two are polydiethoxysiloxanes with potentially higher SiO2 content. PS9150 also contains 7-9% of a titanoxane (Tio2 precursor) group.
(i) Quaternary salt portion of coupling agent has a long, aliphatic group (hydrophobic group).
(j) Quaternary salt portion of coupling agent has only low molecular weight butyl groups.
(k) Equivalent to Dow Corning 2-6040 and Union Carbide A-187.
(1) Methyl methacrylate/y-trimethoxypropylsilyl methacrylate/vinyl pyrrolidone, vinyl-~ methacrylatomethylate copolymer.

A summary of the cla~ses~o~ materials with ratings of 3-5 in Table 2 is the following:

. Polymeric silane coupling agents - item numbQrs 1, 4, 5, 6, 7, 11 . Reactive polydialkoxysiloxanes - item 10 and three (3) footnoted variants . Silicone polymer with pendent reactive oraanic functional groups - item g . Silicone polymer with a chemically attached (block copolymer) hydrophilic, or water soluble, organic polymer - item 8 and three (3) footnoted variants . Low molecular weight, or non-polymeric, 6ilane coupling agents - items 13, 14 and 16.
All the products with a rating of 3 to 5, including PS076 t3) are considered good candidates for use in the process of the present application. Ratin~s of 2 indicate weak activity. Ratings of 1 indicate essentially none is expected.
Various alternates to Gantrez AN169 have been evaluated, these are ~et out in Table 3.

..... .. . .. . _ .. .. ..

-- 132~413 TABLE 3. GANTREZ AN-169 ALTERNATES
-PVP
Item Product Curing No. Number Chemical Type Source Agent Comments (a) (b) l 18,805-0 Ethylene/maleic Aldrich 5 About 50 anhydride Chemical mole copolymer Co. percent maleic anhydride 2 18,293-l Styrene/maleic ditto 5 About 50 anhydride mole copolymer percent maleic anhydride, 50,000 molecular weight 3 18,128-5 Polyacrylic " 5 Molecular acid weight 250,000 4 2348 Polymalaic Poly- 5 Homopolymer anhydride sciences, of maleic Inc. anhydride 3347 Poly(vinyl ditto 4 acetate-maleic anhydride) (a) Same as Table 2 Gantrez AN-169, also rates a 5.
(b) Same as Table 2 ~I; r - 132~13 In addition to the Gantrez AN-169 alternate candidates tested in Table 3, others are also expected to work with equal advantage. These include any polymers or copolymers of acrylic or methacrylio acid, maleic anhydride, crotonic anhydride, or any other carboxyl-group-containing, or nascent carboxyl-group-containing (i.e., a~hydride groups) polymers which are directly soluble in methanol, ethanol, n-propanol, isopropanol, or other lower alcohols, or which are soluble in these alcohols after hydrolysis to the free carboxyl-group-containing polymers. Polymers or copolymers with other strong acid groups such as sulfonic acid or prosphoric acid groups, which are similarly soluble, would also be expected to be usable.
Any organic solvents other than the silicone-swelling alcohols (see Table 1) ethanol through isopropanol, such as methylene chloride, 1,1,1-trichloroethane, MEK, methyl a¢etate and 80 on, which dissolves these polymers or copolymer~, and swells siliaone rubber to some extent are also candidates for use in sllicone rubber treatments, using PVP, or a high vinyl pyrrolidone copolymer as the wettable, slippery coating polymer.
In addition to PVP K-90, lower molecular welght PVP product6 from GAF Corp. may be u~ed ln plaoe of PVP-K90, although they are not expected to be as good in durability.
Higher molecular weight polyvinyl pyrrolidone homopolymer~
if available, would be expected to perform better than PVP
K-90. However, the ea~e of dissolution and the application ease of higher molecular weight products will be dimini~hed as higher solution viscosities are encountered. Vinyl pyrrolidone copolymers, which contain about fifty mole percent or more vinyl pyrrolidone (VP) monomner are expected to show some of the beneficial properties of PVP K-90, if 1~2~13 they are soluble in the same lowe~ alcohols cited above and in Table 1 and can thus be coated on primed silicone (silicone primed with an alcohol solution of Gantrez AN-169 or other appropriate acid-group-containing polymer or copolymer). For example, GAF supplie~ vinyl acetate/vinyl pyrrolidone (e.g., E-735, 70/30 VAc/VP; E-635, 60/40 VAc/VP:
E-535, 50/50 VAc/VP copolymers) and a-olefin/vinyl pyrrolidone copolymers Ganex V-220 and V-216 which are expected to have some utility. Such copolymers of vinyl pyrrolidone with any other comonomer, which are soluble in the lower alcohols, or other appropriate organic treating solvents, are potential candidates to be used in place of PVP.
In addition a new family of polymers from Dow Chemical Company, polyethyloxazoline (PEOX) appears to be usable in place of PVP. Products XAS-10874.01, molecular weight 50,000: XAS-10874.03, molecular weight 200,000; and XAS 10874.05, molecular weight 500,000 are available. These polymers are soluble in water and the lower alcohols. XAS-10874.03 in isopropanol ~2 percent) provide~ a result ~imilar to PVP-K90 when 0.2 percent PS076 is added.
Silicone tubing primed using solution Z-l, then dried and overcoated with this Z-2 substitute, provides a similar wettable, slippery product tubing. Coated directly on vinyl (PVC) tubing this solution provides a similar result to solution Z-2. A sample of this solution ( 1 gram) taken to dryness at 80 C (as in Table 3) provides a product with a water exposure rating of 3.
In addition to vinyl pyrrolidone (VP) copolymers, and polyethyloxazoline (PEOX), there may be other water soluble, or highly water swellable, polymers which can be subst~tuted for PVP. To be usable in the preferred process 132~13 of the present ~nvention, however, they must be soluble in the lower alcohols. Thus rules out a number of polymers which are water soluble but not alcohol ~oluble. Also it must be recognized that other candidates might not all produce a durable slippery coating. This depend~ on what provides the durability of the PVP/PS076 combination. I~
this is due to self-reaction, or crosslinking, of the PS076 to produce an interpenetrating polymer network (IPN) of entangled but not cross-linked PVP, then most, or all other lower alcohol soluble, water soluble polymers of comparable molecular weight probably will work. This includes:
. Polymethacrylamide . Poly(methylvinylether) . Poly(hydroxyethylmethacrylate) . Polyethyleneoxide, or poly(oxyethylene) . Hydroxypropylcellulose.
Additionally polymers soluble in water but not in the lower alcohols may be usable if they and PS076 are together soluble in any other acceptable coating solventa, or if double coating is possible. This is, the polymer may be applied in water solution and the PS076 separately in an alcohol. Such polymers include:
. Polyacrylamide . Polyvinylalcohol . HydroxyethylcellulQse . Poly-2,3-dihydroxypropylmethacrylate.
However, i~ the water soluble polymer must react (cro~slink) with the PS076, or its alternate, not all these candidates will nQcQssarily work. For example PVP may work becausQ of structural imperfections resulting in pendent 8-(n-carboxyethyl) groups which complex with, or react with PS076. Polyacrylamide and polymethacrylam~de can contain 132~ 3 ~ome acrylic (or methacrylic) acid groups which could perform a similar function.
Wh~le the lnvention ha~ generAlly been described above, the detail~ o~ the present invention will be better under6tood by recourse to the following examples and the appended drawings wherein:
Fig. 1 illustrates various ~ilicone flat drains as well as PVC and silicone round drain~;
Fig. 2 illustrates a test apparatus for measuring a level of applied vacuum required to remove clotted blood from the inner surface of several drain configurations;
Fig. 3 is a graph illustrating the average blood clot removal force from several sizes of 6ilicone drains te~ted;
Figs. 4, 5, 6 and 7 are graphs lllustrating the coating advantages of each particular size silicone drain and configuration;
Fig. 8 is a graph showing the average l/8" and 3/16"
diameter PVC drains tested;
Figs. 9 and lO again are graphs revealing the individual performance of each size drain;
Fig. ll illustrates the equipment and experimental set-up for the dynamic vacuum test:
Fig. 12 i6 a plot of the average data collected during the dynamic vacuum test using various PVC and silicone perforated drains;
Fig. 13 illustrates the results obtained in a ~tatic vacuum test on non-coated and coated drains according to the invention;
Fig. 14 i8 a typical set-up for conducting an evacuator vacuum te6t on various test drain~;
Fig. lS repre~ents the average volume collected using a particular form of evacuator with various drain configuration6;
Fig. 16 illustrates the mean variation in blood clot adherence to coatod versus non-coated wound drains:
Fig. 17 illustrates the equipment ~et-up for conducting a porcine ~kin extraction te6t:
Fig. 18 illustrates the drain extraction force through pcrcine ~kin uti~izing non-coated and coated drains.

EXAMPLES

GENERAL_COMMENTS

Unle~s otherwise indicated 6amples of silicone and PVc tubing were utilized throughout in demonstrating the treatment method of the pre6ent invention.

TREATMENT_PROCEDURE_SILICONE AND PVC TUBING
Procedure 1. Individual tubing samples-were cut to 15 inches in length and then marked by cutting out notches at the end of the tubing to indicate its respective reference number. Two holes were also punched out at thi~ same end for sample hanging during the drying step.
2. For silicone tubing the individual tubing was placed in a 16-inch glass tube containing the Gantrez AN-169 sQlution (see Solution Z-1) for 3 minutes. The tubing was then placed in an air-circulating oven at 80C for 15 min-utes.
3. The tubing was removed from the oven, allowed to cool down to room temperature for several minutes.
4. The tubing wa~ then dipped into the polyvinylpyrrolidone/PS076 solution (see Solution Z-2) for 3 minutes.
5. The same drying procedure de~cribed above wa~
carried out, with the exception of the drying time being in-creased to 20 minutes.

For polyvinyi chloride tubing steps 2 and 3 were omitted and step 4 was carried out using a combined poly-vinylpyrrolidone/PS076 solution (see Solution Z-3) in n-propyl alcohol.

132~13 Solutions Z-1 - Gantrez AN-169. Gantrez AN-169 a product o~
the GAF corporation, i~ preferably made up to a 0.25-5.0 percent ~olution in a 1:1 ratio of methanol and isopropanol, and more preferably a 1.0 percent solution will be used.
z-2 - Combined Polvvinyl~yrroliaone ~PVP) and PS076 Solution. PVP K-90, another product of the GAF
Corporation, is added at about 0.25-5 weight percent and preferably at 2.0% weight percent, along with from about 0.1 to about l.o weight percent, preferably about 0.2 weight percent PSo76, to about 97.8 weight percent i~opropanol.
Z-3 - Combined PY~P and PS076 Solution P~P K-90 is added at about 0.25-5.0 weight percent and preferably at about 2.0% weight percent, along with about 0.1 to about 1.0 weight percent, preferably about 0.2 weight percent, PS076 to about 97.8 weight percent n-propyl alcohol.

EXPERI~EN~AL.CONDITIONS AND MATERIALS

A ~eries o~ experiments were conducted utilizing wound drains and evacuator~ manufactured ~rom silicone and polyvinyl chloride materials by Zimmer Patient Care Division (Dover, OH). The silicone drains consists of 7 mm and 10 mm Jackson Pratt type drains. The~e drains are constructed with a round connecting ~evacuator) tube ~.100 I.D. x .187 .D. x 32 in. long), molded to a drainage section ~8 3/4 in.
long), having an elliptical shape in cross section with minor and ma~or axes o~ 3 mm and 4 mm by 7 mm and 10 mm re-spectively. The elliptical drain has three triangular ridges on one wall, to prevent total collap~e from kinking or external pres~ure and to maintain potency of the lumen when a vacuu~ is applied~ The drainæ are perforated with 13~413 offset holes the total length of the elliptical shaped sec-tion ~Figure 1).
Two ~izes of round 6ilicone and polyvinyl chloride drains were used in this investigation. Physical dimension~
of the two silicone round drains were .062 I.D. x .125 O.D., (l/8") with a middle perforated section of 12 inches and a .loo I.D. x .188 O.D., (3/16"~ drain having a middle perforated section if 15 3~4 inches, both drains were 42 inches in total length. The PVC drains were .062 I.D. x .125 O.D., (1/8") with a 12 inch middle perforated section and a .125 I.D. x .188 O.D., (3/16") drain having a 15 3/4 inch middle perforated section, total length of both drains were 42 inches. Half of each round drain was coated with hydrogel in accordance with the procedure outlined above and the other non-coated half served as the control. Total length of the elliptical (flat) drains were coated and uti-lized in the6e experiments while non-coated flat drains from the same manufacture lot number provided controls. The in-side diameter of both PVC and Silicone drains were com-pletely coated, whereas the coating on the outside diameters included the total perforations and up to the location spot.
Beyond thi~ spot the outside diameters were not coated.
Citrated fresh porcine whole blood and commer-cially prepared sheep plasma was used in these expQriments.
Coagulation was initiated by the addition of a calcium chloride (CaCl2) solution. Coagulation times were determined by the Lee White TQst. Zimmer Low Pressure/-Demand Volume Irrigation~ unit served as a vacuum source while Bio-Tek~ pressura tranducers were used to verify pressure readings. A Gralab~ electronic timer was utilized for timed experiments. Drain extraction forces and physical ~32~13 properties data were determinéd utilizing an Instron\
testing device.

EXAMPLE I
This invitro experiment wa~ conducted to measure the level of applied vacuum required to remove clotted porcine blood from the inner surface of each drain configu-ration. The test apparatus was set up in the following manner (Figure 2). A non-coated and coated sample were in-serted into the ~ide port of separate looo ml flask, elimi-nating all connectors. The drains were sealed around the port by soft moldable clay. The vacuum ~ource was connected to the top of the two flask via a Y-connector. A Bio-Tek pressure transducer wa~ installed in the vacuum line leading to the vacuum display on the LP/DVI for a more accurate negative pre6sure readout. A shallow tray supporting the test drains was placed on a horizontal plain, level with the sidQ ports on the flask. Both drains were clamped off approximately 1 inch from the flask side ports and a vacuum applied to the sy~tem for leakage checks. 600 ml of porcine blood to which calcium chloride was added, was poured into the tray covering both drain~ ~approximately 2 inches deep).
The vacuum level was slowly incrQased until blood was drawn through both drain tubes and began dripping into the flask, thus fillin~ both tubes with treated blood. A minimum negative pressure wa~ maintained to hold the blood in the tubes. The blood alot time was ad~usted for 5 minutQs via the Lee White test although a waiting period of 10 minutes was e~tablished before starting the test. Both drain tubes were then rai~ed from the clotted mass of blood, the vacuum was slowly increased in increments of 10 mmHg every 10 seconds until the clots were evacuated. ImmediatQly after - 132~
the clot was evacuated from either tube, that tube was clamped off at the flask and vacuum was increa~ed on the non-patient tube until it evacuated or the vacuum pump reached its operating limit. The minimum level of vacuum necessary to evacuate the clotted blood was recorded.
Figure 3 exhibit~ the average blood clot removal force from all 8ize9 of silicone dra~ns tested, i.e. 7 mm, 10 mm flat, 1/8 in. and 3/16 in. round. Figures 4, 5, 6 and 7 reveal the coating advantages of each partiaular size silicone drain and con~iguration. The graphs indicate both silicone test drains ~coated a~d uncoated) are attached to a common vacuum source ~tarting at 0 mmHg as indicated in the left corner of the graphs. As the vacuum i~ increased, the clot releases from the coated drains at an average of 43 mmHg and the pressure drops to zero on the Bio-Tek attached to that drain. That drain is immediately clamped off and the vacuum continues to be increased on the non-coated drain until the clot is releaaed or the maximum vacuum limit of the LP/DVI machine is reached.
Figure 8 shows the average of 1/8 in. and 3/16 in.
diameter PYC drains tested. Figures 9 and 10 reveals the individual performance of each size drain. Again, the coated PVC drain allows the clotted blood to be evacuated with les6 than 50 mmHg vacuum while the non-coated drain remains blocked in excess of 200 mmHg.
Results of the blood clot removal data demon-strates that coating PVC and silicone wound drains using the process of the present invention substantially reduces blood clot adherence to the inside surfaces o~ the drain as indi-cated by an approximately 500% decrease in vacuum required to remove the clot from the drain. In 75% of the non-coated drains a vacuum in excess of 200 mmHg dld not move the clot - 13~13 and even 300 mmHg in some samples. In all ca~es the alot was evacuated from the coated drain with le~s than 90 mmHg vacuum.

EXAMPLE II
Dynamic vacuum Te~t Equipment and experimental set-up for the Dynamic Vacuum Test is illustrated in Fig. 11. It uses the same apparatus and sample set-up procedure as the blood clot re-moval experiment of Example I except each collection flask is located on its own digital readout balance. Thus allow-ing for data collection on the amount of fluid collected by each drainage tube at any specifia time during the test.
Sheep plasma ~upplied by Polyscience Ina. was used in t~is evaluation. Coagulation was initiated by the addition of calcium chloride solution and ad~usted for a clot time between three and four minutes.
In this experiment the treated plasma was immedi-ately poured into the tray, covering the test drains. The vacuum was ~et at 8 mmHg and a reading taken every minute of the amount of plasma flowing through each coated and non-coated drain. Five minutes into the test the vacuum was increased to 30 mmHG and allowed to stabilize for 1 minute, then the vacuum was increased to 60 mmHg and 85 mmHg respectively. The volume of the plasma collected from the non-coated drains was an average of 13 ml and after 4 minute~ all flow had stopped, indicating the drains were totally occluded. The coated drains continued to be patent for 6 minutes ~50% longer) and delivered a total of 43.5 ml of plasma (234% increase).

Figure 12 i~ a plot of the average data coll~cted on 1~8 in. PVC and silicone perforated drains. This graph 1326~13 clearly illustrates the advantage of the low friction aoat-ing of the present invention on PVC and silicone wound drains, specifically in the length of time they remained patent and in the increase in volume of plasma collection at identical negative pressures when compared to a non-coated wound drain.

EXAMPLE III
Hemovac~ Volume Test This experiment was designed to evaluate the benefits of low friction coated wound drains when they are attached to a Zimmer 400 ml compact evacuator (Hemovac~).
The Hemovac~ devices were set-up with one utilizing a non-coated drain and the other using a coated drain according to the present invention, see attached tFigure 13). Both drains were submerged in a common supply of fresh wholQ
porcine blood that had been treated with calcium chloride.
Coagulation time was between 5 and 6 minutes. Both evacuators were separately monitored with Bio-Tek pressure monitors and compressed until both evacuators wera at equal vacuum, then released at the same instant and allowed to draw in coagulated ~lood until the Bio-Teks lndicated a constant vacuum reading for a minimum of 5 minutes and no drainage into the evacuator could be observed. Vacuum readings were taken every minute during the evacuation process. After all drainage had stopped each evacuator was weighed for total net weight gained and converted into volume of fluid collected, expre6sed in milliliters.
Figure 14 represents the average volume collected using a 400 ml compact evacuator tHemovac-~ with various drain configurations, i.e. 1/8 in. and 3/16 in. round perforated PVC, 10 mm flat and 3/16 in. round ~ilicone l 326413 drains. The low friction coated drain collected 56% more coagulated blood over a 43% longer time period than the non-coated drains.

EXAMPLE IV
static vacuum Test This test was established to measure the effec-tiveness of the low friction drain coated in accordance with the present invention at very low vacuum pressures which occurs in all evacuator device~ as they approach full capacity. A Low Pres~ure - Demand Volume Irrigation unit was used as a constant vacuum source with a Bio-Tek monitor ln-line to verify pressure readings. The test samples were submerged in a tray of calicified porcine whole blood with a coagulation time between 11 and 12 minutQs ~Figure 11). The vacuum was maintained ~t 10 mmHg throughout this test until the two drain~ were totally occluded with clotted blood.
The total volume of blood accumulated in each flask was de-termined and plotted on Figure 15. The data on thls graph represents the mean volume accumulated over a serie~ of tests which included 7 mm, 10 mm flat and 3/16 in. silicone drainst 1/8 in. and 3/16 in. PVC round drains, coated and non-coated.
The chart indicates a 30% increase in volume col-lected over the same time period at 10 mmHg, as compared to the non-coated drains.

~lood Clot Adh~sion The accumulation of blood clot adhesion data was recorded from the Dynamic Vacuum Test, Static Vacuum Test and the Hemovac Volume Test (Examples II-IV)~ Each drain 132~413 section (coated and non-coated from each test) was extracted from the tray containing coagulated porcine ~lood, hung in a vertical position for 5 minutes, then weighed. The net ac-cumulation of clotted blood on the drains was determined.
In all cases perforated drain samplee were used during these evaluations and included 7 mm, lO mm flat, 1/8 in./ and 3/16 in. round silicone drains as well as l/8 in. and 3/16 in.
PVC drains. Figure 16 illustrates the mean variation in blood clot adherence to coated versus non-coated wound drains. This data reveals that porcine blood does not adhere well to the low friction coated drain during the co-agulation proce~s. The coated drain~ exhibited an average of 464~ less weight in clotted porcine blood attached to their surface as compared to non-coated wound drains.

EXAMPLE VI
Porcine Skin Ext~action Test This study was de~igned to measure the effec-tiveness and durability of the low friction coating accord-ing to the pre~ent invention on the outside diameters of the drain by pulling through fresh porcine ~kin. AB in the previous experiments of Example~ I-V, the round drain samples were prepared by cutting a middle perforated drain in the center, then coating one half with low friction coating according to the prqsent invention and using the other half as a control. The 7 mm and lO mm flat drains used for control an coated samples were separate items selected from the same production and processing lots of materials.
An Instron Tensile Testing machine with a 10 pound load cell and full scale selection mode of l pound were used for thi,s test. A fixture built to hold a section of fresh - 132~3 porcine skin taken from the lowér bac~ wa~ mounted in the In~tron machine (Figure 17). A wound drain with a trocar attached was pas6ed through a container of water before perforating the porcine skin from the bottom side. Once the trocar exited the skin it was removed and the ~ample drain wa~ tightened in the clamp attached to the Instron load cell. Approximately 7 inches of drain sample was extracted through the skin each test. The crosshead of the Instron was ~et at a rate of 20 inches per minute and the pulling force in pounds was recorded on a strip chart recorder. A
non-coated control drain was pulled through the skin at the beginning and end of each 6eries of tests to establish a comparison value and to verify the characteristics of the porcine skin after repeated testing using the same hole.
Each low friction coated drain was pull~d through the porcine skin ten times which provided a friction profile on the strip chart recorder. Review of this profile indi-cated the durability and adherence atrength of the coating to the drain surface as well as the effectiveness in reducing the force required to pull the drain through the skin.
An avErage extraction force for 1/8 in. PVC, 3/16 in. and 10 mm flat silicone drains is illustrated in Figure 18. The non-coated control values averaged 395 gms. (.87 lbs.) compared to the mean extraction force of 86 gms. (.19 lbs.) for th~ low friction coated drains. This indicate~
approximately 4 1/2 times less effort i8 required to pull the coated drain~ through poraine ~kin then the non-coated drains. This has a direct relation~hip to drain removal from patients and should producs considerably les~ discom-fort.

132~13 The standard deviation of all the data collected over the ten repeated extractions was + 13.6 gms. ~+ .032 lbs.), which signifies the adhe~ive ~trength and durability of the low friation coating on PVC and silicone drain mate-rials .
The results of experiments conducted demonstratethat coating PVC and 6ilicona wound drains with low friction hydrogel using the process of the present invention de-creases the degree to wh~ch clotted blood adheres to the sur~ace, extends potency time of the drains, requires lecs negative pressure for drainage to occur and facilitates the extraction of the drain through skin.
The data provided by these experiments illustrates that the performanee, applieation and effectiveness of polyvinyl ehloride and sllieonQ wound drains may be ~ubstantially improved by coating the surfaces with a hydrogel using the process of the present invention. The hydrogel surface absorbs fluids thus providing a low eoeffieient of frietion for blood elot adhe3ion, while providing a rather soft surfacQ consistency that can contribute to less mechanieal ~frietional) irritation of adjacent tissue~. The drains require less negative pressure to remove blood elots, increase the effeetiveness and effieiency of evaeuation deviee~ by allowing more volume to be evaeuated in the same period o~ time, and remain patent longer than non-eoated wound drains.
While the invention has been described with re-spect to various speeifie examples and embodiments it is to be understood that the invention is not limited thereto and that it can be variously praetieed within the seope of the following elaims.

Claims (23)

1. A process for treating an article or device having a polymeric surface to produce a smooth, durable, slippery coating comprising applying to the polymeric surface of the said article or device a combined solution of polyvinylpyrrdolidone (PVP) and N-trimethoxypropyl silyl polyethylenimine (PSO76) and then subjecting said article or device to the heat/dry cycle.

2. The process of claim 1 wherein the article has a polymeric surface selected from the group comprising silicone and polyvinyl chloride, latex, polyester, polyurethane and thermoplastic elastomers.

3. The process of claim 2 wherein the polymeric surface is silicone, latex, polyester, polyurethane and thermoplastic elastomers.

4. The process of claim 3 wherein the surface of the article or device is first pretreated by applying a solution of poly (methyl vinyl ether/maleic anhydride), and subjecting to a heat/dry cycle, prior to applying said com-bined solution.

5. The process of Claim 4 wherein the poly(methyl vinyl ether/maleic anhydride) is in solution with a 1:1 mixture of methanol and isopropanol.

6. The process of Claim 4 wherein the poly (methyl vinyl ether/maleic anhydride) solution contains from about 0.25 to about 5.0 weight of said poly (methyl vinyl ether/maleic anhydride).

7. The process of claim 4 wherein the poly (methyl vinyl ether/maleic anhydride) solution contains about 1.0 weight percent of said poly (methyl vinyl ether/maleic anhydride).

8. The process of Claim 2 wherein the polymeric surface is silicone, the surface of the article or device is first pretreated by applying a solution of polymethyl (vinyl ether/maleic anhydride) is then subjected to a heat/dry cycle, and is then treated by applying a combined solution of PVP and PS076 in isopropanol and then subjected to a further heat/dry cycle.

9. The process of Claim 8 wherein the combined solution of PVP and PS076 in isopropanol contains from about 0.25 to about 5.0 weight percent PVP and from about 0.10 to about 2.0 weight percent PS076 and the rest isopropanol.

10. The process of Claim 8 wherein the combined solution of PVP and PS076 in isopropanol contains about 2.0 weight percent PVP and about 0.2 weight percent PS076.

11. The process of Claim 8 wherein the first heat/dry cycle is carried out at about 80°C for about 15 minutes and the second heat/dry cycle is carried out at about 80°C for about 20 minutes.

12. The process of Claim 2 wherein the polymeric surface is polyvinyl chloride.

13. The process of Claim 2 wherein the polymeric surface is polyvinyl chloride and is treated with a combined solution of PVP and PS076 in n-propyl alcohol and then sub-jected to a heat/dry cycle.

14. The process of Claim 13 wherein the combined solution of PVP and PS076 in n-propyl alcohol contains from about 0.25 to about 5.0 weight percent PVP and from about 0.1 to about 2.0 weight percent PS076 and the rest is n-propyl alcohol.

15. The process of Claim 13 wherein the combined solution of PVP and PS076 in n-propyl alcohol contains about 2.0 weight percent PVP and about 0.2 weight percent PS076.

16. The process of Claim 13 wherein the heat/dry cycle is carried out at least about 80°C for about 20 minutes.

17. An article or devices having a polymeric surface which has been treated to produce a smooth, durable, slippery coating, said coating being formed by applying to the polymeric surface of the said article or device a com-bined solution of PVP and PS076 and subjecting said article or device to a heat/dry cycle.

18. An article or devices having a polymeric surface which has been treated to produce a smooth, durable, slippery coating, said coating being formed by applying to the polymeric surface of the said article or device a combined solution of PVP and PS076 and subjecting said article or device to a heat/dry cycle, said article having a silicone surface treated in accordance with any of claims 8 through 11.

19. An article or devices having a polymeric surface which has been treated to produce a smooth, durable, slippery coating, said coating being formed by applying to the polymeric surface of the said article or device a combined solution of PVP and PS076 and subjecting said article or device to a heat/dry cycle, said article having a polyvinyl chloride surface treated in accordance with claims 13 and 16.

20. An article or device having a polymeric sur-face treated in accordance with Claim 1 which is tubular in shape.

21. An article or device having a polymeric sur-face treated in accordance with Claim 1 which is flat in shape.

22. An article or device having a polymeric sur-face treated in accordance with Claim 1 which is suitable for use in surgical procedures.

23. An article or device having a polymeric sur-face treated in accordance with Claim 1 which is suitable for use as a drainage device.