A kind of preparation method and application of high-strength super heat-resistant MC nylon composite material

Abstract

The invention discloses a method for preparing a high-strength super-heat-resistant MC nylon composite material and an application of the composite material in rail transit and belongs to the technical field of polymer materials. The method comprises the steps of dispersing a thermotropic crystallization polymer, a silane coupling agent and short fibers by a double-shaft double-impeller reverse high-speed shearing technique to prepare thermotropic crystallization polymer short fibers and carrying out other conventional steps. According to the invention, due to the adoption of double-shaft double-impeller reverse high-speed shearing force, pretreated short fibers and the thermotropic liquid crystal polymer are dispersed in a caprolactam active compound, short fibers play the role of heterogeneous nucleation and induce lateral crystallization, and thus the crystallinity of the polymer is improved, the size of crystal is refined and the performance indexes such as strength, wear resistance, toughness, heat resistance and the like are improved; at the same time, since the fibrillated surface formed by the thermotropic crystallization polymer and the length-diameter ratio are greater than those of general reinforced fibers, the material is further strengthened and the heat resistance and water absorption of the material are increased and thus the composite material can meet usage requirements of high-speed rails.

Description

technical field [0001] The invention belongs to the technical field of polymer material preparation, and in particular relates to a preparation method of high-strength super-heat-resistant MC nylon composite material and its application in rail transit. Background technique [0002] China has become the country with the fastest development of high-speed railway in the world, the most complete system technology, the strongest integration capability, the longest operating mileage, the highest operating speed, and the largest scale under construction, leading the new trend of high-speed railway development in the world. With the acceleration of railway transportation, polymer material components are playing an increasingly important role in new railway tracks. The rapid development of the plastics industry has further increased the variety and quantity of engineering plastics, especially reinforced and toughened composite materials. Materials for rails require large amounts of ...

AI Technical Summary

Problems solved by technology

[0003] At present, most of the materials used in the high-speed rail industry are PA66 modified materials. Due to its high water absorption rate and poor dimensional stability, and the injection molding method is often used for molding. Low, not easy to heat evenly, high pressure for product molding, huge extruder structure, large investment, and difficulty in large-scale products, etc. In addition, the price of PA66 is much higher than the price of caprolactam, the raw material of MC nylon.

[0004] Nylon material has high strength and toughness, excellent fatigue resistance and a large range of modification, and has a good application prospect in the rail transit industry. The series of rail transit products developed with it have high strength and elasticity. Good quality, light weight, vibration reduction, noise reduction, insulation, wear resistance, corrosion resistance, fatigue resistance and other advantages have been widely used in the rail transit industry, but domestic ordinary single-grade nylon materials are difficult to meet the high strength and high toughness of high-speed rail , high durability and other requirements

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