Thermoplastic polyurethanes of mixtures of hard and soft thermoplast polymers

摘要

Thermoplastic poluyrethane polymers having improved physical properties over a wide temperature range are produced from a physical mixture of thermoplastic polymers of (a) from about 10 to about 90 percent of a soft polymer prepared from an organic isocyanate having an average functionality of about 2 and an organic compound or compounds containing active hydrogen atoms and having an average functionality of about 2 and an average equivalent weight greater than 200 at an NCO to active hydrogen ratio of from about 0.9/1 to about 1.1/1, and (b) from about 90 to 10 percent of a hard polymer prepared by reacting at an NCO to active hydrogen ratio of from about 0.9/1 to about 1.2/1 an organic icocyanate having an average functionality of from about 1.90 to about 2.20 with an organic compound or compounds containing active hydrogen atoms and having an average functionality of about 2 and an average equivalent weight less than 100.