摘要 |
The selective thermodegradation of homo- or copolymers of propylene is carried out, without occurrence of thermooxidation phenomena, by treating the polymer, at 250 to 350 DEG C, with primary and/or secondary antioxidants and a benzopinacol derivative of general formula (I): <CHEM> wherein: for n = 1 and X = 1 Z1 and Z2 together form a <CHEM> group A and B are <CHEM> wherein R1, R2 and R3, are alkyl or aryl radicals; for X ranging from 3 to 20 Z1 and Z2 are aryl radicals, A and B are R1-Si-R2 groups and are part of an oligomer having formula <CHEM> and for n = 0 and X = 1, Z1 and Z2 are aryl radicals, while A represents a <CHEM> or <CHEM> group. o |