abstract |
A process for making a polysiloxane block copolymer which is built up from units of the formula [A] [B], in which A is a polymeric block built up from radically polymerisable monomer, and B is a polysiloxane block, the process comprising the steps of forming a polysiloxane macroinitiator by grafting a radical initiator onto a polysiloxane via a nucleophilic displacement reaction between groups on the polysiloxane and radical initiator respectively, and reacting the polysiloxane macroinitiator so obtained with radically polymerisable monomers in an atom transfer radical polymerisation reaction to form a polysiloxane block copolymer. Also provided are cosmetic and personal care compositions, such as hair styling compositions, containing the polysiloxane block copolymers. |