Thermoplastic cellular polyurethane elastomer and preparation method thereof

Abstract

The invention discloses a thermoplastic cellular polyurethane elastomer which is high in use temperature and good in aging resistance. The thermoplastic cellular polyurethane elastomer comprises, by weight, 100 parts of thermoplastic polyurethane, 0.5-10 parts of expandable microspheres and 0.5-5 parts of adhesives, the melting point of the thermoplastic polyurethane is higher than 180 DEG C, and the initial expansion temperature of the expandable microspheres is higher than 180 DEG C. The thermoplastic cellular polyurethane elastomer has excellent surface quality and mechanical property, the tensile strength retention rate of the thermoplastic cellular polyurethane elastomer is higher than or equal to 90% after aging for 72 hours at the temperature of 100 DEG C, and the thermoplastic cellular polyurethane elastomer can be used for buffer gaskets, buffer blocks and the like.

Description

technical field [0001] The invention relates to the field of thermoplastic polyurethane microcellular elastomers. In particular, it relates to thermoplastic polyurethane microcellular elastomers using expandable microspheres as blowing agents and their preparation. Background technique [0002] The use of thermoplastic polyurethane (TPU) is growing rapidly due to its good processability and excellent mechanical properties, and can be recycled. In recent years, due to the increasing demand for lightweight materials, the development of microporous TPU has become a current research hotspot. [0003] Methods of foaming TPU using chemical blowing agents have not been successful in producing densities less than 0.8 g / cm 3 moldings, and the use of chemical blowing agents tends to produce a coarser foam structure and increase the degree of cavitation. With exothermic blowing agents (azobiscarboxamide), lower foam densities can be achieved, but with poorer surface finishes and lon...

AI Technical Summary

Problems solved by technology

[0006] The expansion temperature of the expandable microspheres used in the above three patent documents is relatively low, and it is only suitable for thermoplastic polyurethane foaming with a low melting point (or softening point). It is suitable for thermoplastic polyurethane foaming at a processing temperature higher than 180°C, especially heat-resistant thermoplastic polyurethane foaming; secondly, the aging resistance at high temperatures is poor, which may easily lead to yellowing of the product and a decrease in mechanical properties

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