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Poly adipic acid diamine (polyamide 66, PA66), has high rigidity (tensile yield stress, flexural modulus), abrasion resistance, heat resistance, chemical resistance and other excellent properties, is widely used in machinery, instrumentation, automotive and other transportation and other fields. In order to meet the diverse requirements of performance, PA66 toughening at home and abroad to improve the rigidity had many fruitful research work. With the use of performance requirements increase, PA66 high performance hot research focused on toughness and rigidity while improving it. In summary analysis PA66 toughening mechanism and influencing factors increase rigidity, based on the design of the work rigidity while significantly improving toughness modified PA66 should have the following structure: In the PA66 can be introduced at the same time improve the rigidity of the filler, the introduction of both react with PA66, but also with the rigid filler surface reaction, but also has toughened and basically does not cause rigidity reduces a multi-functional ingredient in energy effects, entropy effect \PA66, the increase in the toughness of the matrix, but also enriched in PA66 and rigidity between the filler and build a moderately high strength with a flexible interface region. This structure, to avoid the rigid boundary interface and easy to cause microcracks region of the matrix resin; when external force, in a matrix resin and a rigid filler stress transfer between the good, full rigidity fillers improve rigidity and strength effect; the base resin will be mainly shear yielding strain, a robust interface region can effectively terminate shear deformation and crazing, has high impact energy absorption capacity. Based on this, the work of polypropylene, ethylene-propylene elastomers, styrene-butadiene elastomers, epoxy functional groups containing crosslinking agent (G), auxiliary crosslinking agent (S) as the main raw material, the use of \of mixed \PA66/RTMB/GF composite materials. Using hierarchical extraction, infrared analysis (IR), scanning electron microscopy (SEM), polarized light microscopy (PLM), thermal analysis, mechanical performance measurement and other means, RTMB and PA66/RTMB, PA66/RTMB/GF structure and properties of composite materials were characterized reached the following main results and conclusions: (1) RTMB from the unreacted PP, elastomer, PP, elastomer and the crosslinking agent graft copolymer, PP, elastomer formed by the bridging agent The graft copolymer chain connection bridge, the bridge through a polymerization chain bridging connection PP, cross-linked copolymer elastomers, crosslinking agent, homopolymers and copolymers of other components. (2) RTMB PA66/RTMB content on the mechanical properties of impact, when PA66/RTMB composition of 84/16 the best mechanical properties, tensile yield stress, flexural modulus and Izod notched impact strength are PA66 90%, 84% and 308%. (3) PA66/RTMB/GF composites, RTMB the bad and PA66 oxygen functional groups on the molecular chain amino, carboxyl and amine groups GF surface undergoes a chemical reaction between the components to form a chemical bond; PA66 matrix and is formed between the flexible GF moderate strong interface bonding. (4) PA66/RTMB/GF in PA66 thermal crystallization exotherm peak onset temperature and peak temperature than material PA66 items improves the 1.1 ℃ and 1.1 ~ 5.5 ℃; with RTMB content increases, PA66 the nucleation and crystallization rate first increases and then decreases. PA66 GF can induce matrix is ??formed along the transverse crystal glass fiber surface. (5) PA66/RTMB/EPDM/GF mechanical properties of composite materials and processing technology are closely related: first with PA66 GF composite and then with RTMB, EPDM composite two-step method, PA66 first with RTMB, EPDM compound and then with GF composite compared to two-step method, using PA66, GF, RTMB, EPDM composite step method were comprehensive mechanical properties of the composite material is best; and screw speed 40r/min, 120r/min in comparison to the system when the screw speed 90r/min composites obtained the best overall mechanical properties. (6) GF content of 20%, with the increase of the content RTMB, PA66/RTMB/GF tensile yield stress, flexural modulus and Izod notched impact strength first increased and then decreased; RTMB content of 10% , with the increase of the content GF, PA66/RTMB/GF the mechanical properties of the composite increased gradually when PA66/RTMB/GF composition of 60/10/30, the tensile yield stress, flexural modulus and Izod notched impact strength were increased to 1.73 times raw materials PA66, 2.72 times, 3.86 times. (7) the composition of 60/20/20 PA66/RTMB/GF composite thermal deformation temperature of 201 ℃, than the starting temperature of thermal deformation of PA66 (69.8 ℃) increased significantly.
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