| 摘要 |
Thermoplastic polyurethanes derived from hexamethylenedi-isocyanate and a polyol mixture based on polytetramethylene glycol, 1,6-hexanediol and optionally other polyols and chain extenders. Thermoplastic polyurethanes (TPU) derived from: (A) 100-60 mol% hexamethylenedi-isocyanate (HDI) and 0-40 mol% other aliphatic di-isocyanates; (B) 30-100 wt% polytetramethylene glycol (B1) and 0-70 wt% other polyols or polyol mixtures (B2) with a number-average mol. wt. (Mn) of 600-5000; (C) 80-100 wt% 1,6-hexanediol (C1) and 0-20 wt% other chain extender(s) with an Mn of 60-500; with the optional addition of (D) catalysts; and (E) conventional additives, etc. In this system, the equivalent ratio of (A):(B) = (1.5:1.0)-(10.0:1.0) and the NCO index is 95-105; the amounts of components (B1) and (B2) are 40-100 wt% and 0-60 wt% respectively if (B1) has an Mn of 600-1600, or 30-70 wt% and 70-30 wt% respectively if (B1) has an Mn of 200-590; components (C1) and (C2) are not the same as (B1). An Independent claim is also included for moulded products obtained from TPU as described. |
