FREMGANGSMAATE FOR SUSPENSJONSPOLYMERISASJON AV VINYLKLORID

摘要

1291170 Polymerizing vinyl chloride SHINETSU CHEMICAL CO 22 Dec 1970 [23 Dec 1969 29 Dec 1969] 60896/70 Heading C3P Vinyl chloride is polymerized in aqueous suspension in the presence as initiators of in which R1 is C 1 -C 6 alkyl, alkoxy or aryl and in which each R2 and R3 is C 1 -C 4 or a monomersoluble organic peroxide. In one embodiment when a peroxide is used as second initiator, this is added after up to 50% polymerization has been effected. When both initiators are nitriles an alkaline medium may be used. In examples (1) is the 2,4,4-trimethyl, or 4-methoxy-, -ethoxy-, -butoxy- or -phenyl-2,4-dimethyl derivatives of 2,21-azobis-valeronitrile and (2) is 2,21 - azobis - 2,4 - dimethyl - valeronitrile or -caponitrile, acetylcyclohexylsulphonyl peroxide, diisopropyl peroxydicarbonate or lauroyl peroxide.