Block copolymers of lactone and lactam, compatabilizing agents, and compatibilized polymer blends

摘要

This invention relates to high molecular weight block copolymers of &egr;-caprolactone and &ohgr;-lauryl lactam prepared by sequential bulk polymerization using a mixture of at least one anionic polymerization initiator and optionally at least one co-initiator. A preferred continuous sequential bulk reactive extrusion process comprises feeding a mixture of &ohgr;-lauryl lactam, at least one anionic polymerization initiator, and at least one co-initiator into the first (i.e., upstream) hopper of an extruder, and thereafter feeding &egr;-caprolactone into a second (i.e., downstream) hopper of the extruder. The preferred continuous sequential bulk reactive extrusion is solvent free, rapid (typical mean and maximum residence times in the extruder being no more than about 20 minutes and 30 minutes respectively), and produces a high conversion of monomers to block copolymer. The poly(&egr;-caprolactone/&ohgr;-lauryl lactam) block copolymers compatibilize the blending of otherwise immiscible or poorly miscible polymers to form polymer blends having improved mechanical and thermal properties. Accordingly, the block copolymers can be compounded with chlorine containing polymers and other polymers such as polyamides, anhydride polymers such as maleic anhydride, and the like. To improve the impact resistance of the compatibilized blend, impact modifiers can be utilized such as maleic anhydride modified EPM, EPDM, and the like. To improve thermal and mechanical properties, thermal performance modifiers can be utilized such as maleic anhydride polyolefins or maleic anhydride modified polymers made from vinyl substituted aromatic monomers.