摘要:
Thermoplastic polyurethanes and molding compositions containing the same having improved surface resistance (writing and scratch resistance) and good industrial processability, and the use thereof, such polyurethanes prepared by reacting: (a) one or more organic diisocyanates; (b) a chain extender comprising at least one low molecular weight polyol having on average at least 1.8 and not more than 3.0 Zerewitinoff-active hydrogen atoms and a number-average molecular weight Mn of 60 to 400 g/mol; and (c) at least one polyol component having a number-average molecular weight Mn of 450 to 10,000 g/mol and on average from at least 1.8 to not more than 3.0 Zerewitinoff-active hydrogen atoms; wherein the ratio of the number of isocyanate groups in component (a) to the number of isocyanate-reactive groups in components (b) and (c) is 0.9:1 to 1.1:1; in the presence of (d) a mixture of polyorganosiloxanes of the general formula (R2SiO)n, in an amount of 0.4 to 10 wt. % based on the thermoplastic polyurethane, wherein each R independently represents an organic hydrocarbon radical having 1 to 27 carbon atoms which can be linear and/or branched, and n represents an integer of 3 to 6000, wherein the mixture consists of (d1) 0.2 to 2 wt. %, based on the thermoplastic polyurethane, of one or more polyorganosiloxanes (R2SiO)n wherein n=3 to 300 and (d2) 0.2 to 8 wt. %, based on the thermoplastic polyurethane, of one or more polyorganosiloxanes (R2SiO)n wherein n=1000 to 6000.
摘要:
Light-stable, thermoplastic polyurethanes with good processability and having an ASTM D-1003 haze value of less than 10%, the polyurethane prepared by a process comprising: reacting: (a) a diisocyanate component comprising 1,6-hexamethylene diisocyanate; (b) a chain extension component consisting of (b1) 1,4-di(β-hydroxyethyl)hydroquinone and (b2) at least one chain extender selected from the group consisting of diols having a 2 or 3 carbon atom chain length between the two OH groups, in a molar ratio of chain extender (b1) to chain extender (b2) of 10:1 to 1:4; and (c) at least one polyol component having a number average molecular weight of 450 to 10000 g/mol, and an average number of Zerewitinoff-active hydrogen atoms of at least 1.8 to at most 3.0; wherein the ratio of isocyanate groups in component (a) to isocyanate-reactive groups in components (b) and (c) is 0.9:1 to 1.1:1.
摘要:
Light-stable, thermoplastic polyurethanes with good processability and having an ASTM D-1003 haze value of less than 10%, the polyurethane prepared by a process comprising: reacting: (a) a diisocyanate component comprising 1,6-hexamethylene diisocyanate; (b) a chain extension component consisting of (b1) 1,4-di(β-hydroxyethyl)hydroquinone and (b2) at least one chain extender selected from the group consisting of diols having a 2 or 3 carbon atom chain length between the two OH groups, in a molar ratio of chain extender (b1) to chain extender (b2) of 10:1 to 1:4; and (c) at least one polyol component having a number average molecular weight of 450 to 10000 g/mol, and an average number of Zerewitinoff-active hydrogen atoms of at least 1.8 to at most 3.0; wherein the ratio of isocyanate groups in component (a) to isocyanate-reactive groups in components (b) and (c) is 0.9:1 to 1.1:1.
摘要:
The present invention relates to novel intrauterine systems and to methods for manufacturing these systems. An intrauterine system according to the invention comprises a reservoir and a continuous, closed and flexible frame. The frame comprises a thermoplastic polyurethane elastomer made of a polycarbonate diol, 1,6-hexamethylenediisocyanate, and a chain extender.
摘要:
The present invention relates to novel intrauterine systems and to methods for manufacturing these systems. An intrauterine system according to the invention comprises a reservoir and a continuous, closed and flexible frame. The frame comprises a thermoplastic polyurethane elastomer made of a polycarbonate diol, 1,6-hexamethylenediisocyanate, and a chain extender.
摘要:
This invention concerns thermoplastic polyurethane mouldings with improved surface resistance (resistance to writing and scratching) and very good technical processability as well as their use.
摘要:
This invention concerns thermoplastic polyurethane mouldings with improved surface resistance (resistance to writing and scratching) and very good technical processability as well as their use.