Study On Improving Anti-wear Property Of Polyoxymethylene

The glass transition temperature of polyformaldehyde(POM)is low,it is-40 °C,and the molecular chain of the non-crystalline part of it can move freely at normal temperature,so its product has very good wear-resistant self-lubricating effect.Due to the wear-resistant lubricating properties of POM,its parts can be used in many friction environments,such as automotive bearing materials,gears,buckles,window coverings,etc.In the past one or two years,POM has rapidly occupied market share in various fields due to its good price advantage.However,with the improvement of people's use requirements,the wear resistance of ordinary POM can no longer meet the demand,and it is necessary to modify and improve its wear resistance of POM..In this paper,the wear resistance properties of imported and domestic polyformaldehyde were studied by universal friction and wear testing machine,universal material testing machine and impact testing machine.It was found that imported polyoxymethylene had smaller friction coefficient,lower wear and better physical properties than domestic polyoxymethylene.Three kinds of wear-resistant additives(No.A,B,C)were selected in this paper.The effects of different wear-resistant additives on the wear resistance of POM were studied by friction and wear tester,melt indexer and impact tester.It is found that A wear-resistant auxiliaries have better wear resistance than the other two wear-resistant auxiliaries,and the friction coefficient,friction noise and wear amount are small,the elongation at break in mechanical properties is greatly improved,and other properties are not improved significantly.However,B and C wear-resistant additives have certain improvement on the wear resistance of polyacetal,but the effect is not as good as A,and the wear-resistant additives B and C will cause the physical properties of POM decreased.Through the industrial application simulation of wear-resistant auxiliaries,the applicability of wear-resistant auxiliaries A was verified.The results show that the wear-resistant auxiliaries A have obvious effects on the wear resistance of polyoxymethylene,and have no effect on the physical properties of polyoxymethylene.Auxiliary A is fully suitable for improving the wear resistance of polyoxymethylene products.