COPOLYAMIDES COMPRISING UNITS DERIVED FROM M-XYLYLENE- AND HEXAMETHYLENE- DIAMINES, ADIPIC ACID AND AT LEAST ONE OTHER DICARBOXYLIC ACID; USE IN BARRIER FILMS

摘要

Partially aromatic copolyamides (I) comprising the following monomer components (in wt.%) and opt. additives are new: (a) hexamethylene diamine (5-30); (b) meta-xylylene diamine (10-40); (c) adipic acid (15-50); and (d) at least one aliphatic 7-10C dicarboxylic acid, pref. sebacic acid and/or azelaic acid (5-45); provided that the sum of (a) - (d) is 100 and the acid and amino gps. are present in approx. equimolar amts. Also claimed are: (A) transparent barrier layers of (I), esp. for multi-layer packaging materials; and (B) mono- or multi-layer packaging materials contg. at least one of these barrier layers and/or at least one barrier layer comprising a mixt. of (I) with other thermoplastic polymers, esp. ethylene vinyl alcohol polymers.