Dynamic vulcanization thermoplastic polyurethane/polysiloxane elastomer and preparation method thereof

Abstract

The invention discloses a preparation method of a dynamic vulcanization thermoplastic polyurethane / polysiloxane elastomer. The preparation method comprises the following steps: firstly premixing thermoplastic polyurethane, methyl vinyl siloxane, a reinforcing filler and a chain extender, then carrying out melt extrusion pelletization inside an internal mixer or a double screw extrusion machine together with a catalyst to prepare a polyorganosiloxane master batch, then uniformly mixing thermoplastic polyurethane, the polyorganosiloxane master batch, a compatilizer and a polymerization inhibitor, and then adding a cross-linking agent and the catalyst for dynamic vulcanization. The methyl vinyl siloxane used for preparing the master batch is relatively low in viscosity and easy for good dispersion, and simultaneously chain growth can also be realized under the effect of the catalyst, and the viscosity and molecular weight of polyorganosiloxane are improved, so that the obtained elastomercan be of preferable mechanical property and sooth hand feeling, is easy for machining, and can be used in the application fields with high requirements such as buildings, automobile spare parts, electric wires and cables, medical apparatus and instruments and wearable equipment.

Description

technical field [0001] The invention belongs to the technical field of thermoplastic elastomer and its preparation, and in particular relates to a dynamically vulcanized thermoplastic polyurethane / polysiloxane elastomer and a preparation method thereof. Background technique [0002] Thermoplastic polyurethane (TPU) is a kind of (AB) n-type block that contains many repeating carbamate groups (-NH-COO-) in the molecular chain and is alternately connected by flexible segments and rigid segments. copolymer. Among them, the rigid segment acts as an elastic cross-linking point at room temperature, making it an elastic material between ordinary rubber and plastic. TPU elastomer has a wide range of hardness. Although it can be used in a wide range of fields, such as auto parts, industrial hoses, gears, shoe materials, etc., it can be used in some special elastic material applications such as wearable device accessories and automotive interior parts. TPU is difficult to meet the re...

AI Technical Summary

Problems solved by technology

However, this invention still does not improve the compatibility of polysiloxane and organic polymer matrix, and it is prone to phase separation or poor interfacial bonding.

Chinese patent CN102153853 provides a silicone rubber / polyurethane thermoplastic elastomer, and a certain amount of silicon-modified polyurethane is added to the formula as a compatibilizer, but due to the large difference in viscosity between silicone rubber and polyurethane, there is still the problem of poor dispersion

Since the above technical solutions all adopt the direct addition of silicone rubber as the rubber phase, there will be some problems: ①Because of the high molecular weight and high viscosity of silicone rubber, it is difficult to directly add materials, and special feeding and processing equipment are required. high investment

②Because silicone rubber does not have the fluidity of thermoplastic resin at high temperature, the viscosity of the resin matrix is ​​quite different, and it is difficult to disperse evenly, so that the performance of the thermoplastic elastomer obtained cannot be guaranteed

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