The Forming Board Method Of Compression Molding And Its Theoretical Research

Foaming board has excellent mechanical properties, it can be widely used in packaging, wind power, transportation and the other field. Compression molding is more used in industry, because the products are obtained more easily than the other methods, the price of the equipments is very low. When the thickness of the foaming sheet is considerably thick, this method has several drawbacks, such as, long production period, low efficiency, more cost. To work out this problem, we can open diffusion holes in moulded foaming motherboard, so the saturating time is shorted, thus the production efficiency is improved. This paper systematicly studys the influence of diffusible paths on the saturating time. This paper optimizes the diffusible paths to enhance the efficiency of moulded foaming. Through the optimization of the moulded foaming process reduce the influence of the diffusible paths on the performance of the products.In order to optimize the mode of the arrangement of the diffusible paths, CO2 sorption and desorption rate into/from SAN was measured with gravitational method, and get the diffusible coefficients under different foaming condition, firstly. DOE, a software for choosing optimized technical conditions, was used for this experiment. By using of DOE, this paper systematically studies the influence of parameters of foaming process on the capacity of gas adsorption and foaming ratio, and the optimal foaming process parameter is determined.By means of designing diffusible paths on the motherboard of SAN polymer in advance, could enhance the productivity of molding foaming. The holes were punched and distributed in the way of equilateral triangle after deduction and contrasting. This method not only could reduce consumption of resources, but also could reduce the likelihood of product defects. The diffusion model of gas into polymer sheet with holes had been established. The model could reveal the phenomenon of diffusion reliably. Using the method of punching obviously improved the efficiency of the molding foam. Compared with the motherboard without diffu The less the distance from one hole to another, the more the adsorption. As much shorten the distance of the holes as possible, without affecting the quality of the products.Finally, the influence of different foaming process for the diameter of the diffusible holes was discussed. We found that with different pressure foaming method or using different foaming temperature method were unable to prepare the products without any drawbacks. Then temperature controlling method was put forward, and this method could produce the products without any diffusible holes. Based on the method of temperature controlling, limited method were studied, with the direction perpendicular to the diffusible holes. The results showed that the influnce of limited method on the closure of diffusible holes was effective.