Low temp bulk (co) polymn of vinyl chloride - in presence of secondar alkyl iodides mol wt regulators

摘要

Tactic PVC with reduced mol. wt. is obtained by (co) polymerisation of vinyl chloride, in bulk, with the aid of redox catalyst of the "boron trialkyl/oxidising agen" type, at 0 degrees C. Reaction is effected in presence of (a) cyclic alkyl iodides of formula R'-CHI-R" (where R' and R" are alkyl, aryl, or aralkyl; or R'+R" is -(CR2)x- where x is =3, R is H, aryl or alkyl; total number of C-atoms is 3 to 15, used as 0.5 to 10 wt.% w.r.t. vinyl chloride. Prodcuts are easily process-able at rel. low temps. and are not liable to degradation and discolouration.