Articles made from hydrophilic thermoplastic polyurethane compositions
An article is prepared by injection molding, wherein the article is formed from a hydrophilic thermoplastic polyurethane composition, wherein the thermoplastic polyurethane composition comprises the reaction product of a hydroxyl terminated polyol intermediate component, an aliphatic isocyanate component, and, optionally, a chain extender component. For injection molding, the hydrophilic thermoplastic polyurethane has a crystallization temperature measured by dynamic scanning calorimetry of at least 75° C.
1. An injection molded article comprising a thermoplastic polyurethane consisting of the reaction product of one poly(ethylene glycol) having a number average molecular weight of 1400 to 8000, an aliphatic diisocyanate selected from the group consisting of isophorone diisocyanate (IPDI), 1,4-cyclohexyl diisocyanate (CHDI), decane-1,10-diisocyanate, lysine diisocyanate (LDI), 1,4-butane diisocyanate (BDI), 1,5-pentanediisocyanate (PDI), hydrogenated xylene diisocyanate (HXDI), and hexamethylene diisocyanate (HDI) or mixtures thereof, and a chain extender selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,3-butanediol, 1,5-pentanediol, neopentylglycol, 1,4-cyclohexanedimethanol, 2,2-bis[4-(2-hydroxyethoxy) phenyl]propane, hexamethylenediol, heptanediol, 3-methyl-L5-pentanediol, ethylenediamine, butanediamine, hexamethylenediamine, hydroxyethyl resorcinol and mixtures thereof, wherein the thermoplastic polyurethane composition has a crystallization temperature of at least 75° C. measured by DSC, wherein the isocyanate component and chain extender component make up a hard segment of the thermoplastic polyurethane and wherein the thermoplastic polyurethane comprises at least 10 wt % hard segment.
2. The injection molded article of claim 1 wherein the thermoplastic polyurethane comprises at least 13 wt % to about 50 wt % hard segment.
3. The injection molded article of claim 1 wherein the thermoplastic polyurethane has a water absorption range of at least 70% as measured by ASTM D570.
4. The injection molded article of claim 1 wherein the thermoplastic polyurethane has a water absorption range of at least 100% as measured by ASTM D570.
5. The injection molded article of claim 1 wherein the aliphatic diisocyanate consists of hexamethylene diisocyanate.
6. An injection molded article comprising a thermoplastic polyurethane consisting of the reaction product of one poly(ethylene glycol) having a number average molecular weight of 1400 to 8000, hexamethylene diisocyanate, and 1,4-butane diol, wherein the hexamethylene diisocyanate and the 1,4-butane diol make up a hard segment of the thermoplastic polyurethane, wherein the thermoplastic polyurethane composition comprises 10 wt % to about 30 wt % hard segment, wherein the thermoplastic polyurethane composition has a water absorption range of at least 100% as measured by ASTM D570, and wherein the thermoplastic polyurethane composition has a crystallization temperature of at least 75° C. measured by DSC.