Low temperature impact resistant, easily flowing, thermoplastic polyurethane elastomer compositions, a process for their preparation and their use

Low temperature impact resistant, easily flowing, thermoplastic polyurethane elastomer compositions, comprising a mixture of thermoplastic multiblock polyurethane elastomers having different hardnesses and optionally reinforcing fillers wherein the thermoplastic polyurethane elastomers are prepared by reacting:

• a) organic diisocyanates with:
• b) polyhydroxyl compounds having molecular weights of from 500 to 8,000;
• and
• c) diols having molecular weights of from 60 to 400 in an equivalent ratio of NCO groups from said organic diisocyanates (a) to the total of the hydroxyl groups from said components (b) and (c) of from 1.0:1.0 to 1.2:1.0 wherein the thermoplastic polyurethane elastomer compositions comprise:
• A) 5 to 95 parts by weight of at least one thermoplastic polyurethane elastomer (A) having a Shore A hardness of less than 95 wherein components b) and c) taken together have an average hydroxyl equivalent weight of greater than about 200;
• B) 95 to 5 parts by weight of at least one Shore A hardness of greater than 98 whereby the parts by weight of (A) and (B) total 100 parts by weight wherein components b) and c) taken together have an average hydroxyl equivalent weight of from 110 to about 200;
• and
• C) 0 to 60 weight percent based on the weight of (A) and (B) of reinforcing filler;
• with the proviso that the flexible segment of the thermoplastic polyurethane elastomer (A) and (B) comprises either both polyester segments or both polyether segments.