摘要:
A mixture of hydroxy-terminated hydrocarbons useful as a mold release agent for polymers is disclosed. The polymers suitable in the present context are the ones prepared by polyaddition or polycondensation, in particular, thermoplastic polyurethane and polyurethane urea.
摘要:
A process for producing a thermoplastic polyurethane film by means of sintering a particulate thermoplastic polyurethane in a heated mold, is described. The thermoplastic polyurethane has: (i) a melt index of 20 to 100, measured at 190° C. and under an applied force of 21.2 N; (ii) a relative solution viscosity of 1.15 to 1.45, the relative solution viscosity being determined by, measuring the viscosity (a) of a solution of 0.4 grams of the thermoplastic polyurethane in 99.7 grams N-methyl-2-pyrrolidone containing 0.1% dibutylamine at 25° C., measuring the viscosity (b) of N-methyl-2-pyrrolidone containing 0.1% dibutylamine at 25° C., and dividing viscosity (a) by viscosity (b); and (iii) a Shore hardness of 80 to 98.
摘要:
A light-colored thermoplastic molding composition comprising a polyurethane elastomer is disclosed. The polyurethane which is the reaction product of at least one polyol, at least one organic diisocyanate and at least one polyol chain extender contains one or more pentaerythritol diphosphites color stabilizers conforming to a specific formula exhibits improved color stability and improved processability. The process for preparation entails introducing the stabilizer before the reaction has been completed.
摘要:
The present invention relates to a process for the production of molding compositions, which can easily be released from the mold. These molding compositions comprise thermoplastic polyurethanes with a hardness of 45 to 65 Shore A, with good mechanical properties, with low shrinkage and good low temperature properties.
摘要:
A continuous process for the production of thermoplastically processable polyurethane elastomer is disclosed. The process comprise adding acid H compounds in an amount calculated to control and render constant the melt viscosity of the product. The inventive elastomer has constant melt flow behavior and high thermal stability.
摘要:
The present invention relates to thermoplastically processable polyurethane elastomers (TPU) with tensile strengths of >35 MPa (measured in accordance with EN ISO 527-3), with shrinkages of
摘要翻译:本发明涉及拉伸强度> 35MPa(根据EN ISO 527-3测量)的热塑性可加工聚氨酯弹性体(TPU),其收缩率小于3%,并且基于至少使用自熄性 一种可以内置的防火剂,其制备方法及其用途。
摘要:
This invention relates to thermoplastically processable, readily demouldable moulding compositions with low shrinkage and with a hardness of 65 to 85 Shore A, consisting of a mixture of A) a thermoplastic polyurethane of hardness 60 to 75 Shore A and B) a thermoplastic polyurethane of hardness 76 to 90 Shore A, which is produced continuously by a special multi-stage process.
摘要:
A process for the continuous preparation of melt processable polyurethane elastomers having improved softening behavior is disclosed. The process entails reacting a polyisocyanate, a polyol and a chain extender, which have a temperature of at least 170° C., in a static mixer, wherein the reaction mixture is prepared. The reaction mixture is then metered into an extruder into which optional auxiliaries and/or further components are fed.
摘要:
Process for the continuous preparation of thermoplastically processable polyurethane elastomers with improved softening properties is disclosed. The process is carried out in a tubular reactor at a ratio of the circumferential speed of the stirrer (in m/sec) in the tubular reactor and the throughput (in g/sec) of >0.03 m/g.
摘要:
The invention relates to a process for continuously producing thermoplastically processable polyurethanes with improved softening behaviour in a sequence of static mixers.