Investigation on the mechanical, thermal and electrical properties of polyoxymethylene composites modified by thermoplastic polyurethane elastomer and carbon fiber

Abstract

As we all know, adding thermoplastic polyurethane elastomer(TPU) into Polyoxymethylene(POM) by melt blending can not only improve its toughness, but also improve the brittleness and cracking of POM products at low temperatures. However, there are some problems in the use of above POM/TPU modified material. For example, after adding TPU, the strength and rigidity of POM resin will be significantly reduced, and its antistatic performance is not very good. In this paper, we use melt-extrusion blending method to improve the strength, rigidity and antistatic properties of toughened POM material by adding CF. In addition, the aggregation and properties of the blends are studied by DSC, FTIR, PLM, DMA and mechanical tests, surface resistivity. Mechanical analysis show us that the tensile strength, flexural modulus increase significantly with the increase of CF content, and the notched impact strength of the POM/TPU/CF materials are all better than that of the pure POM resin. It can also be found that after adding 2% to 8% CF, the surface resistivity of the composites gradually decreases with the increase of CF content, and CF forms a conductive network in the POM matrix. The anti-static test shows that when the CF content is 6% the surface resistivity of POM/TPU/CF blend is 109Ω, and when the CF content is 8% which can reach to 104Ω.