Abstract: In a polyvinyl butyral (PVB) sheet plasticized with a multiester of an alcohol having 2 to 4 hydroxyl groups and a C.sub.16 to C.sub.20 unsaturated fatty acid having a hydroxyl group attached to the acid molecule, which sheet does not craze polycarbonate or polyacrylate when in contact therewith, the addition of a synergistically effective amount of a monoester of a glycol and such C.sub.16 to C.sub.20 acid improves the low temperature penetration resistance and adhesion properties of such sheet without significant loss in its resistance to stress cracking polycarbonate or polyacrylate in a laminated glass assembly.

Abstract: In a polyvinyl butyral (PVB) sheet plasticized with a multiester of an alcohol having 2 to 4 hydroxyl groups and a C.sub.16 to C.sub.20 unsaturated fatty acid having a hydroxyl group attached to the acid molecule, which sheet does not craze polycarbonate or polyacrylate when in contact therewith, the addition of a synergistically effective amount of a monoester of a glycol and such C.sub.16 to C.sub.20 acid improves the low temperature penetration resistance and adhesion properties of such sheet without significant loss in its resistance to stress cracking polycarbonate or polyacrylate in a laminated glass assembly.