<p>t-Butyl peresters as polymerisation initiators. New cpds. of general formula: RR'R"C-CO-O-O-CMe3 where R, R' = 1-3C alkyl R" = 3-10C (cyclo)alkyl esp. Me2CH-CMeHCH2-CEt2-CO3tBu and These peresters initiate polymerisation of olefins and hardening of e.g. polyester resins. Compared with t-butylperpivalate, they permit better control of the polymerisation and have a lower vapour pressure.</p>
