Process for preparing a (meth)acrylate additive, a method of improving the sag resistance of a polyolefin and a sag resistant polyolefin

A process for preparing a (meth)acrylate comprising:

• preparing an aqueous phase by combining water, one or more stabilizing agents including poly(N-vinyl pyrrolidone), and one or more surfactants selected from anionic surfactants and cationic surfactants;
• preparing an oil phase by combining one or more free radical initiators, a first monomer blend of one or more monomers capable of undergoing radical polymerization, one or more crosslinking and/or graft-linking monomers, and stearyl methacrylate and/or lauryl methacrylate, wherein the free radical initiator is capable of partitioning preferentially into the oil phase;
• combining the aqueous and oil phases and mixing to form a suspension having oil droplets ranging in size from 1 to 10 microns;
• and
• raising the temperature of the suspension to effect an initial polymerization forming a core polymer;
• adding a solution which comprises a second monomer blend of one or more monomers capable of radical polymerization after the initial polymerization to effect a second polymerization, wherein the first and second monomer blends do not have the same composition;
• adjusting the temperature for the second polymerization;
• adding a flow aid to form a core/shell polymer suspension;
• and
• spray drying the core/shell polymer suspension to form a free flowing powder of core/shell polymer.