| The morphology structure and the state of aggregation can be controlled by polymer processing conditions.The physics properties of polymers can be improved by controlling of processing conditions. Vibration technology in injection molding is one of the technologies applied to improve properties of polymers.The physics properties of normal injection molding and vibration injection molding are compared in this paper. The relationship between the mechanical properties,crystal structures,viscosity and processing conditions such as vibration frequency,vibration pressure,mold temperature was investigated.The main results are summarized as follows:(1) The tensile strength of samples produced by vibration injection molding is higher than the samples produced by normal injection molding.Tensile strength are increased as the increasing of the vibration frequency and vibration pressure,when vibration frequency reaches to 0.47Hz,the tensile strength are not increased any more.(2) The crystal structure changes are observed by WAXD. Theγform of nylon6 can be decreased by vibration injection molding. The a form are much more than theγform in subsurface of the sample which are produced by vibration injection molding.(3) The melt peak width of subsurface is wider than the melt peak width of core,in vibration samples. This phenomenon shows that there are smaller spherocrystal in subsurface of vibration samples.The crystallinity of subsurface is higher than crystallinity of core in some vibration samples.(4) The spherocrystals in subsurface are observed by SEM. The number of spherocrystal in sbusurface are much more than in core. This phenomenon proves that vibration effect can produce more crystal nucleus.(5) The vibration time of high vibration frequency samples is longer than the low vibration frequency samples. This shows that the high vibration frequency produced much more heat, the viscosity of polymer decreased sharply, the gate freezing needs more times.
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