Compatible thermotropic liquid crystal polymer and method and application thereof

Abstract

The invention discloses a thermotropic liquid crystal polymer and a method and the application thereof. By selecting monomer, the invention designs the molecular structure to directly prepare thermotropic liquid crystal polymer polyester-imide (TLCPEI) which has the similar chemical structure as special engineering plastics polyetherimide (PEI) so that when the operation of in situ composition is carried out, the thermotropic liquid crystal polymer can has favorable compatibility without using a third substance, such as compatibilizer, and the like; and the addition quantity of the TLCPEI is lower than or equal to 10 percent according to the percentage by weight. The thermotropic liquid crystal polymer has the advantages that the over-all properties of composite materials are obviously improved, and the production cost is greatly reduced; and therefore the invention is favorable to the industrialization and the commercialization of the products.

Description

technical field [0001] The invention relates to the field of polymer composite materials, in particular to a compatible thermotropic liquid crystal polymer and its preparation method and application. Background technique [0002] Thermotropic liquid crystal polymer (TLCP) / polyetherimide (PEI) in-situ composites were prepared by melt blending method. Due to the excellent performance of liquid crystal itself and appropriate processing technology, the addition of liquid crystal polymer can indeed improve PEI. The processability of the matrix, at the same time, the liquid crystal phase can form microfibers in situ in the matrix, so that the tensile strength and modulus of the composite material increase with the increase of the liquid crystal phase content, achieving a strengthening effect. However, this relatively significant enhancement effect is often achieved by adding a high amount of liquid crystal polymer. The amount of liquid crystal polymer added in the composite system...

AI Technical Summary

Problems solved by technology

However, this relatively significant enhancement effect is often achieved by adding a high amount of liquid crystal polymer. The amount of liquid crystal polymer added in the composite system reported in domestic and foreign literature is generally 10wt% to 90wt%. Good mechanical properties can only be obtained when the amount of additives is as high as 50wt%, and the liquid crystal phase almost becomes the main substance, which invisibly greatly increases the cost of the material

At the same time, due to the selection of commercial liquid crystal polymers, their chemical structures have been fixed, and most of these TLCP products have poor compatibility with the PEI matrix, resulting in high interfacial tension and low interfacial adhesion between the two phases, making the liquid crystal phase in In the process of compounding, the in-situ fiber formation cannot be done well, which limits the degree of improvement of the mechanical properties of the composite material and affects the ductility and toughness of the material.

There are still many researchers who focus on adding the third component as a compatibilizer to solve the problem of poor compatibility between components, but the subsequent choice of compatibilizer and the appropriate amount of compatibilizer Problems such as the complex multi-phase structure of the multi-component system and the complex multi-phase structure make the research and application of composite materials more difficult.

Images