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Publication numberUS2127896 A
Publication typeGrant
Publication dateAug 23, 1938
Filing dateJan 14, 1937
Priority dateAug 13, 1936
Publication numberUS 2127896 A, US 2127896A, US-A-2127896, US2127896 A, US2127896A
InventorsVohrer Herbert
Original AssigneeVohrer Herbert
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Method of producing elastic objects from polyvinyl alcohols
US 2127896 A
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Description  (OCR text may contain errors)

\ Patented Aug. 23, I938 UNITED STATES METHOD OF PRODUCING ELASTIC OBJECTS FROM POLYVINYL ALCOHOLS Herbert Vohrer, Berlin, Germany No Drawing. Application January 14, 1937, Se-

rial 1936 '1 Claims.

My invention relates to the production of elastic articles from a polyvinyl alcohol.

Hitherto elastic articles, f. e. hoses, threads, bands, packings, membranes, etc., have been produced from polyvinyl alcohols insoluble in cold water by pressing a mixture of polyvinyl alcohol and softening agents, and a quantity of water exceeding the quantity which the used softening agents are able to withhold at temperatures from 70 to 130 C. Thereafter the ready article had to be freed from the excess of water contained therein by drying and this process caused a certain shrinkage of the article. As the dryingprocess may, according to the form of the article, take up to several days, and as the shrinkage can not be exactly predetermined so that the size of the article in its final form is often different from the desired size, the use of an excess of water is not only very disadvantageous but it makes it even impossible to produce articles having a considerable wall thickness as the drying of such articles would take an economically unbearable space of time.

It has been proposed to replace the excess of water by a surplus of softening agents, however, herewith the high percentage of softening agents in the articles caused such a strong "sweating" of them in moist air that this process could not be used in practice.

30 Now I have found that the usual mixture of a polyvinyl alcohol with 15 to 50 parts by weight of softening agents can be used for producing elastic articles even without any water or with just that quantity of water which the softening agents are able to withhold, if the temperature at which the pressing is effected, is raised to between 135 and 180 C. The pulverized mixture of polyvinyl alcohol and softening agents can either be worked at this temperature into a kneadable caoutchouclike mass and then be pressed into the desired form, or it can be formed in the cold state and then be pressed at the above mentioned temperature. In both cases articles of any form and with any desired wall-thickness can be obtained which do not need any drying but are completely finished as soon as they leave the press. The pressing operation can be performed by means of a worm press or piston-press in order to enable the continuous production of hoses, bands and threads; or a stamping-press may be used for producing packings, membranes and the like. The production of the last mentioned articles can also be effected by the known die casting process.

In producingarticles from polyvinyl-alcohols according to my method the same organic or in- In Germany August 13,

organic filling substances may be used as with the known methods; they may be soluble in water and glycerin or insoluble. I1 soluble filling substances are used, such as glue, starch, dextrin or the like, then the percentage of softening agents admixed to the polyvinyl alcohol must be increased according to the added quantity of filling substances.

The composition of the mixtures to be used with the method according to the invention shall be illustrated by the following examples:

I. parts by weight of. polyvinyl alcohol, 40 parts by weight of glycerin.

II. 55 parts by weight of polyvinyl alcohol, 10 parts by weight of a 50% solution of glue in water, 35 parts by weight of ethylene-glycol.

III. 40 parts by weight of polyvinyl alcohol, 20 parts by weight of starch, 10 parts by weight of a 50% solution of glue in water, 30 parts by weight of glycerin.

IV. 25 parts by weight of polyvinyl alcohol, 25

parts by weight of starch, 25 parts by weight of inorganic filling substances, and 25 parts by weight of glycerin.

What I claim is:

1. A method of producing elastic objects from polyvinyl alcohols comprising preparing a mixture containing a polyvinyl alcohol, 15 to 50% by weight of softening agents and not more water than the quantity of softening agent present in the mixture is able to withhold, working up such mixture into a kneadable mass, pressing such mass into the desired form and heating such pressed mass to a temperature of to C.

2. A method according to claim 1 in which said mixture is worked up into a kneadable mass at a temperature between 135 and 180 C. prior to the pressing operation.

3. A method of producing elastic objects from polyvinyl alcohols comprising preparing a mixture containing a polyvinyl alcohol, 15 to 50% by weight of softening agents and not more water than the quantity of softening agent present in the mixture is able to withhold, working up such mixture into a kneadable mass, shaping such mass into the desired form in the cold state and subsequently subjecting such shaped mass to pressure at a temperature between 135 and 180 C.

4. A method of producing elastic objects from polyvinyl alcohols comprising preparing a mixture containing a polyvinyl alcohol, 15 to 50% by weight of softening agents, organic filling substances, and not more water than the quantity of softening agent present in the mixture is able to withhold, working up such mixture into a kneadable mass, pressing such mass into the desired form and heating such pressed mass to a tempereture of 135 to 180 C.

5. A method of producing elastic objects from polyvinyl alcohols comprising preparing a mixture containing a polyvinyl alcohol, 15 to 50% by weight of softening agents, inorganic filling substances, and not more water than the quantity 0! softening agent present in the mixture is able 10 to withhold, working up such mixture into a kneadable mass, pressing such mass into the desired form and heating such pressed mass to a temperature of 135 to 180 C.

6. A method according to claim 1 in which said mixture is pressed by the die casting process.

7. A method according to claim 1 in which said mixture is pressed by extrusion through a heated nozzle.

Z'ERBERT VQHRER.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2563661 *Sep 16, 1948Aug 7, 1951Johnson & Son Inc S CFabric-treating composition and method of preparation
US2565686 *Sep 16, 1948Aug 28, 1951Johnson & Son Inc S CFabric-treating composition and method of preparation
US2618796 *May 5, 1949Nov 25, 1952United Shoe Machinery CorpStiffening uppers of shoes
US2650170 *Jan 27, 1951Aug 25, 1953Du PontCoating material, coated fabric, and process for producing it
US2917045 *Dec 10, 1958Dec 15, 1959Air ReductionFace mask and similar devices having body-conforming means
US3044974 *May 20, 1959Jul 17, 1962Kurashiki Rayon CoMethod of preparing polyvinyl alcohol filaments containing starch or derivatives thereof
US3143518 *Jun 21, 1963Aug 4, 1964United Resin Products IncHot melt polyvinyl alcohol adhesive plasticized with propylene glycol
US3442848 *Mar 8, 1967May 6, 1969Kuraray CoPolyvinyl alcohol sizing compositions containing deliquescent compounds and plasticizers
US3472804 *May 16, 1966Oct 14, 1969Ledoga SpaInsoluble films based on polyvinyl alcohol and process for the preparation thereof
US4323492 *Dec 1, 1980Apr 6, 1982Hoechst AktiengesellschaftPlasticizer containing polyvinyl alcohol granules
US4460562 *Mar 30, 1983Jul 17, 1984Key Pharmaceuticals, Inc.Polymeric diffusion matrix containing propranolol
US4466953 *Sep 30, 1982Aug 21, 1984Key Pharmaceuticals, Inc.Polymeric diffusion matrix
US4470962 *Apr 28, 1981Sep 11, 1984Key Pharmaceuticals, Inc.Polyvinyl alcohol, polyvinylpyrrolidone, transdermal drugs
US4492685 *Jan 30, 1984Jan 8, 1985Key Pharmaceuticals, Inc.Portection of burned or wounded patients
US4542178 *Dec 2, 1983Sep 17, 1985Hoechst AktiengesellschaftMolding materials
Classifications
U.S. Classification264/211.21, 524/21, 524/18, 264/349, 524/52, 450/156
International ClassificationB29C43/00, C08K5/00
Cooperative ClassificationB29K2029/04, C08K5/0016, B29C43/003
European ClassificationC08K5/00P1, B29C43/00B