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:
Dec. 19, 1978
Filed:
Jan. 06, 1977
Vasanth R Kamath, Tonawanda, NY (US);
Pennwalt Corporation, Philadelphia, PA (US);
Abstract
A process for the free-radical polymerization of vinyl monomers, including vinyl aromatic monomers, at at least two distinct progressively higher polymerization temperatures, each between the temperatures of about 70.degree. C to about 150.degree. C in the presence of at least two free-radical initiators, one of which initiators, used in relatively minor proportions, has the formula ##STR1## wherein x is a numeral from 1 to 5 inclusive, B is ##STR2## A is hydrocarbyl, A, is tertiary hydrocarbyl and R is A, a hydrocarbyloxy or alkylperoxy and the other initiator, used in relatively major proportions, has a 10 hour half-life temperature below about 100.degree. C. The distinct temperatures for polymerization may occur as separate parts of a polymerization in which the temperature of the system continually increases.