Melt blending acid or anhydride-crafted block copolymer pellets with epoxy resin

A process to produce an epoxy resin composition comprising the steps of:

• a) providing from 1 to about 100 parts by weight of pellets having an average particle size within the range of 0.05 in. to 0.3 in. of modified hydrogenated block copolymer comprising at least one block comprising predominantly polymerized monoalkenyl aromatic hydrocarbon monomer units, and at least one block comprising predominantly, before hydrogenation, polymerized conjugated diolefin monomer units, the hydrogenated block copolymer having been modified by grafting substantially to the blocks of polymerized conjugated diolefin monomer units, on the average, between about 2 and about 200 maleic anhydride functional groups for each polymer molecule of modified hydrogenated block copolymer;
• b) melt blending the modified hydrogenated block copolymer with 100 parts by weight of an epoxy resin;
• c) agitating the blend by high shear mixing under conditions sufficient to react an amount of the maleic anhydride functional groups with epoxy groups of the epoxy resin effective to provide a stable dispersion of modified hydrogenated block copolymer in the epoxy resin;
• and
• d) recovering an epoxy resin composition.