| With the development of auto, machinery and power-generating equipment and textile industry, the requirements of high performance engineering plastics are increasing. Single component plastics can not meet the multiple demands. Employing blending modification technology to produce plastic alloy of excellent comprehensive properties have recently been the subject of intense interest. It is supported by the technology development fund project of Machine Industry Department. According to the aim of improving auto components self-lubricate, higher anti impact, friction and wear resistant and decreasing their weight, and the basic principle of polymer blending modification, PA6/UHMWPE plastic alloy is prepared. This paper discussed the preparation technics, compatibility, the effect of compatibilizer, mechanics property, friction and wear property and its theory.The preparation of HDPE-g-MAH is studied, which act as the compatibilizer of PA6 and UHMWPE, then the various effecting factors in the grafting polymerization are analyzed, such as the quantity of initiator and monomer, screw rotate speed and reaction temperature. By means of reaction extrusion, with the complex initiator exist, the HDPE-g-MAH blend of high grafting rate can be prepared. The infrared spectroscopy study shows that the reaction between MAH and HDPE is chemical reaction, and the MAH acid anhydride groups are grafted on the chain of HDPE. The quantity of initiator effect the grafting reaction of HDPE and MAH, the homopolymerization reaction of MAH, and the cross-linking reaction between radicals of macromolecule chain. The more initiator added, the higher speed of grafting reaction can be obtained, but at the point when 0.8(wt.%) initiator is added, the speed show the peak value, above this point the speed decreased as the initiator is added more.The grafting rate can also be increased by adding more monomer MAH, and it can be reached 1.35% when the quantity of MAH is 4%. Furthermore, reaction temperature and screw rotate speed have great effect on grafting polymerization. The study result shows that the high performance polymer with high grafting rate can be obtained at the 170～190℃ and rotate speed is 30～45r/min.Blending system of PA6 and UHMWPE is studied emphatically in this paper. The result shows that PA6 and UHMWPE are incompatible thermodynamics system. Putting the compatibilizer HDPE-g-MAH into the blending system can decrease the interfacial energy between two phases, and promote dispersal of phases and enhance the combination force between phases. Thus the morphology and structure are more stable. It has been concluded that the compatibility of blending system can be increased and the combination between polymers' interfaces can be strengthened by putting the compatibilizer into the incompatible polymer blending system.The effect and mechanism of compatibilizer HDPE-g-MAH in the PA6/UHMWPE blending system are studied. The blend has been characterized by Molau, Infrared spectroscopy, SEM and DSC. The results show that the acid anhydride group of HDPE-g-MAH and amiocyanogen or imine group of PA6 take place chemical reaction, and form grafting copolymer, which act as compatibilizer in the PA6/UHMWPE blending system and improves the dispersion, interphase morphology and mechanical property. When 10～20(wt.%) compatibilizer was added the tensile strength and flexural strength were increased, absorption rate and rheological property of blend are decreased. With the increasing of the amount of UHMWPE, anti impact strength was improved obviously. Comparing with PA6, anti impact strength was increased by 4～5 times when 15(wt.%) compatibilizer and 30(wt.%) UHMWPE were added.The effect of compatibilizer on the friction and wear resistant property of the blending system are studied. With the increasing of the amount of the compatibilizer, coefficient of friction is decreased, wearing amount is reduced, but when too much compatibilizer is added, the effect occurs in the system. When the grind wheels' rotate speed is accelerated,...
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