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. 15, 1987
Filed:
Jun. 27, 1986
Sadao Ikuma, Suzuka, JP;
Mitsubishi Monsanto Chemical Company, Tokyo, JP;
Abstract
A method for producing by suspension polymerization a copolymer comprising a vinyl cyanide compound and an aromatic vinyl compound having excellent transparency, and uniform composition, and a content of the polymerized residue of vinyl cyanide compound in the range of from 50 to 85% by weight comprising the steps of: (a) carrying out initial charging of the total quantity of the vinyl cyanide compound and a partial quantity of the aromatic vinyl compound at a compositional ratio, wherein the content of the vinyl cyanide compound in the resulting copolymer attains an intended ratio within a range of from 50 to 85% by weight; (b) initiating the copolymerization reaction by adding a polymerization initiator having a decomposition half-life at 95.degree. C. of two hours or longer to the compounds charged in previous step after the reaction system is elevated to a temperature corresponding to a decomposition half-life T of the polymerization initiator and (c) carrying out the copolymerization reaction, elevating temperature of the reaction system along a temperature corresponding to the decomposition half-life of the polymerization initiator, while immediately and continuously feeding the remainder of the aromatic vinyl compound to the reaction system.