Study On The Toughening And Reinforcing Effects Of Particle-Filled PA-6 Composites

In attempt to prepare and investigate the toughening and reinforcing effect of polymer composites, the binary and multicomponent composites were prepared with polyamide-6 (PA-6) served as the matrix, the inorganic filler particles and elastomer particles with different modulus as modifiers, based on the state-of-art development in the realm of polymer/inorganic and polymer/polymer composites domestically and overseas. In this paper, the relationship between the structure and properties of particle-filled PA-6 composite was studied systematically. Deep investigation and analysis on high performance, application and theory of polyamide 6 composites were carried out. A lot of valuable information was obtained that can be used for development of polyamide 6 composites. The main works and conclusions were listed as following:l.The crystallization behaviors of binary particle-filled PA-6 composite were examined. The particles filled in PA-6, not only changed the structure of the composites, but also changed the crystallization behaviors .It was showed that nano-CaCO3 particels have nucleating effect which process percolation behaviors, while elastomer particels with in weak interface adhension has nucleating effect, too.2.The composites of PA-6 filled with CaCO3 particles were studied. The effect of the viscosity of the matrix phase on the morphology and the mechamcal propertiesof PA-6/CaCO3 composites were observed. The fracture surface of PA-6/nano-CaCO3 composites and the state of dispersion of nano-CaCO3 in the PA-6 matrix were analysed by using SEM and TEM. The results indicated that in the higher viscosity of the matrix phase, the nano-CaCO3 particles can be dispersed more uniform and the impact strength of the composites exhibited increased. The nano-CaC03 particels filled composite show pseudoplastic fluid, and the viscosity n increased with the increasing of content of nano-CaCO3 particels.3.Two-phase elastomer particles with different modulus TPE-1 and TPE-2 were prepared by adopting in-situ grafting in melt state, and the relationship between the structure and properties of PA-6 filled with these elastomer particles composite was studied systematically, firstly. Effect of interfacial adhension, processing conditions the modulus of elastomer, and composition on the dispersing morphology and properties of PA-6/POE and PA-6/TPE blends were investigated. The results showed that these elastomer particles with different modulus did not induce evidence different phase size and phses distribution, and high interfacial interaction and high shear rate during processing were found to produce fine and uniform dispersion of elastomer in PA-6 matrix. This suggests that there is an optimal rubber particle size for PA6 to toughen, and the composite with 20wt% of elastomer has an increase in impact strength by 11 times. The results also showed that elastomer particles with high modulus were better for improving the tensile properties whereas the impact strength was the same as that of low modulus. And the brittle-ductile transition of system became easy.4.The relationship between the structure and properties of ternary composites of PA-6/CaCO3/Maleated ethylene-octane copolymer (POE) was investigated. It was found that CaCO3 particles in micrometer and nanometer combine with POE give the same much of synergistic toughening. The effect of blending routes on the morphology and properties of ternary composite have been analyzed by using a state mechanical test, DMA, TEM and SEM. It was found that POE, as a impact modifier, has a profound effect upon the toughness of the PA-6/nano-CaCO3composite. In particular, by adopting two-stage blending route, the micro-structure of the ternary composites turned to core-shell structure, and the impact toughness has been improved greatly. At the same time, tensile strength and dynamic storage modulus (E' ) are higher than those of adopting one-stage blending route ternary composite. The results of our investigation also suggest that PA-6/POE/n-CaCO3 ternary composites with soft shell-rigid c...