Properties Comparation Of Blended Modification Of PA6 With Three Polyolefin

In this paper, HDPE/PA6, UHMWPE/PA6 and PTFE/PA6 composites were prepared in different proportion by the extrusion and injection moulding process with POE-g-MAH as compatilizer. The mechanical properties, water and moisture absorption properties, friction and wear behavior of composites were studied. And the microstructure images of the tensile surface, impact fracture surface and worn surface were observed using the electronic stereomicroscope. The modification mechanism of composites is analyzed based on those results. Relevant research results were as follows:The mechanical properties of PA6 composites are investigated and the results indicate that:the addition of three polyolefin to PA6 makes impact strength of composites increased, and causeed the tensile strength, flexural strength, flexural modulus and hardness decreased in different degree, the breaking elongation of HDPE/PA6 was the largest and 48% more higher than pure PA6 when the content of HDPE was 20%, but that of UHMWPE/PA6 and PTFE/PA6 composites decreased obviously. The microstructure images revealed the compatilizer POE-g-MAH improved compatibility of HDPE/PA6 best in all PA6 composites, because micro-bumps were more uniformly distributed on the microscopic surface of HDPE/PA6 and two-phase interface was fuzzy, indicating that compatilizer had played a good cohesive role between HDPE and PA6.The friction and wear behavior of PA6 composites were examined and the results showed that:the friction coefficient and wear mass loss of PA6 composites decreased and fluctuated slightly with the increase of three polyolefin compared with PA6 when samples were abraded smooth steel wheel. Wear resistance of UHMWPE/PA6 was better and its wear mass loss was about 18% of PA6. Abraded inlaid carborundum steel wheel, the friction coefficient of PA6 composites decreased, but the wear mass loss had different changing rule. Wear resistance of HDPE/PA6 was better and wear mass loss was 41% of PA6 with the load of 200N.The water and moisture absorption properties showed, water and moisture absorption of PA6 composites obviously decreased with the increase of polyolefin,HDPE/PA6 had optimum water resistance in three composites, and water absorption was only 15% of that of PA6. Water and moisture absorption of HDPE/PA6 reaches saturation at the 70th day and 30th day respectively, saturated moisture absorption rate is about 50% of the water absorption. After water absorption, the tensile strength, flexural strength and flexural modulus of PA6 composites decreased and the breaking elongation increased greatly.In the experimental condition, comparative study on performances of PA6 composites blended with three polyolefin revealed that:HDPE/PA6 composite had better comprehensive properties, and glass fiber and carbon fiber were beneficial to enhance the mechanical properties, friction and wear behavior of HDPE/PA6 composite.