Process for making graft polyols using t-amyl peroxy free radical initiator

A process for the preparation of a stable, low viscosity, high solids content graft polymer dispersion, said process comprising polymerizing in situ at least one ethylenically unsaturated monomer with a macromer containing from 0.001 to 0.09 moles of induced unsaturation per mole of said macromer in the presence of and effective amount of a chain transfer agent and a free radical initiator mixture, wherein said free radical initiator mixture comprises a blend of t-amyl peroxy (2-ethylhexanoate) and 1,1′-bis(t-amyl peroxy) cyclohexane at a weight ratio of from 1:10 to 1:2.

A process for the preparation of a stable, low viscosity graft polymer dispersion, said process comprising polymerizing in the presence of a free radical initiator mixture (a) at least one ethylenically unsaturated monomer with (b) a polyol mixture comprising (1) a polyoxyalkylene polyether polyol having an equivalent weight from 100 to 10,000;

• and (2) a macromer containing an effective amount of induced unsaturation, wherein said free radical initiator mixture comprises a blend of t-amyl peroxy (2-ethylhexanoate) and 1,1′-bis(t-amyl peroxy) cyclohexane at a weight ratio of from 1:10 to 1:2.