Mechanical Performance Research And Simulation Of Micro-foaming Polymer

Microcellular foamed polymer material is a new material having a range size of 1-100μm, cell density 107-109cells/cm3. Microcellular foamed polymeric material to the solid polymeric material has a variety of advantages. Including the decrease of material cost and weight, good chemical resistance, low heat and electrical conductivity, and good noise abatement performance. But the micro-foamed polymer materials and products for use as a structural material, in addition to the requirements of the above properties, it also requires a higher mechanical properties. The researchers made a lot of work, Improve the overall mechanical properties in two ways: First, to improve the quality of the cell(bubble size, number of bubbles, the degree of dispersion) to reduce stress concentration and improve the uniformity of deformation; Second, by adding reinforcement to improve mechanical properties. But all the way over the use of physical foaming technoloy, physical foaming device complexity, high cost, which greatly limits the scope of application of foamed polymer material.In this paper, the different characteristics of polypropylene material, prepared by chemical foaming micro-foam resin composites, research the relationship between the structure and mechanical properties of the micro-materials resin, reinforcement, gas three-phase coexistence conditions The effect of the mechanism of interfacial behavior and the quality of the expanded polypropylene foam composites reinforced toughened. And through the ANSYS finite element software to model, simulate the force under circumstances surrounding cell stress- strain variation and deformation law of macroscopic mechanical properties of foamed polypropylene materials and products were forecast. This provides experimental and theoretical basis for the expansion of the industrial application of micro-foam material. Thesis achieved the following key results:(1) When the expansion ratio is consistent, favorable small cell size to improve the mechanical properties of micro-foam composite. With reduced cell size, impact strength and tensile strength increased, the impact strength increase ratio of 29.1%; tensile strength ratio increased 6.8%.(2) When the consistent expansion ratio and cell number, with the decrease of the degree of dispersion, the impact strength and tensile strength gradually increased, impact strength increased from 3.398 KJ.m-2 to 4.88 KJ.m-2; stretch strength increased from 25.62 MPa to 26.33 MPa.(3) ANSYS establish different cell size and the dispersion models, when the size of a small, small dispersion, the stress, the amount of deformation are relatively small, and the stress- strain have from three-phrase to two-phrase.(4) in the PP / GF composite system, with a coupling agent KH560 modified PP / GF composites optimal mechanical properties, tensile strength is 59.14 MPa, compressive strength is 70.69 MPa, toughness is 10.14 KJ.m-2.(5) adding enhanced foamed polypropylene material phase, the mechanical properties are significantly improved. High melt strength PP and PP(T30S) as a tensile strength of the matrix, respectively 41.69 MPa and 40.05 MPa, impact strength were 8.26 KJ.m-2 and 6.97 KJ.m-2, compressive strength 42.90 MPa and 48.51 MPa respectively.