Non-reactive hot-melt adhesive with lactide-based copolymer

摘要

A hot-melt adhesive includes a copolymer having first and second blocks, wherein the first block is an amorphous copolymer of lactic acid and a further polymerisable monomer and the second block is a polylactic acid polymer selected from poly-L-lactic acid (PLLA) and poly-D-lactic acid (PDLA), the first block having a number average molecular weight of at least 0.5 kg/mol and the second block having a number average molecular weight of at least 1 kg/mol. Preferably, the hot-melt adhesive also has 0.5-20 wt. %, calculated on the weight of the copolymer of a polylactic acid unit (PLAU) which has a stereochemistry which is opposite to the stereochemistry of the second block in the copolymer. The non-reactive hot-melt adhesive combines a good adhesive performance with storage stability resulting from a low cold-flow. Further, the adhesive is at least partially based on polymers which can be prepared from renewable resources.