Claims
- 1. In a process for thermally reversing cross-links in a cross-linked composition by heating to about 175.degree. to 300.degree.C. and then cooling to reform a cross-linked composition wherein said composition comprises an intimate mixture of a vinyl interpolymer having reactive anhydride groups and a polyfunctional cross-linking agent, the improvement which comprises employing a cross-linking agent selected from the group consisting of hydrogenated 4,4'-isopropylidene diphenol, hydroxyalkyl diethers of 4,4'-isopropylidene diphenol and hydroxyalkyl diethers of hydrogenated 4,4'-isopropylidene diphenol wherein said hydroxyalkyl ether group in each case contains from 2 to 4 carbon atoms, employing a vinyl copolymer having from about 5 to 25 mole percent of an unsaturated dicarboxylic acid anhydride and employing a catalytic amount of a monoalkyl or a dialkyl phosphoric acid wherein the alkyl group contains from about 5 to 18 carbon atoms; said cross-linking agent present in an amount to provide about 0.05 to 0.5 moles of hydroxyl per mole of anhydride.
- 2. The process of claim 1 wherein said anhydride is maleic anhydride.
- 3. The process of claim 1 wherein said vinyl copolymer is a copolymer of styrene and maleic anhydride.
- 4. The process of claim 1 wherein the catalyst is di-(2-ethylhexyl)phosphoric acid.
REFERENCES
This application is a continuation-in-part of U.S. application Ser. No. 672,981, filed on Oct. 5, l967 and now abandoned.
US Referenced Citations (3)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
672981 |
Oct 1967 |
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