The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 20, 1992
Filed:
May. 17, 1991
Chan I Chung, Troy, NY (US);
Other;
Abstract
The processibility during fabrication of a vinyl chloride polymer is improved by reducing the melt viscosity of the polymer when heated for shaping, by the admixture therewith of a small amount up to about 5% by wt of at least one melt-compatible normally crystalline solid solvent as a processing aid. At temperatures below the melting point of the solid solvent and the glass transition temperature of the polymer, the solid solvent deposits within the solid polymer as microdispersed solid microparticles which do not significantly adversely affect the mechanical properties of the solid polymer, whereas upon heating above the melt temperature of the mixture, the molten solid solvent is compatible with the molten polymer thereby effectively reducing its melt temperatures and melt viscosity during processing. Solid solvents found suitabe for vinyl chloride polymers are saturated carboxylic acids and their low molecular weight derivatives which have a crystalline melting point of at least about 80.degree. C., preferably about 100.degree. C., but not higher than about 180.degree. C. and do not exert substantial permanent solvent effect on PVC. The solid solvent can be mixed directly with the polymer or via a carrier polymer containing the same.