| Being a kind of linear polymer with high crystallinity, polyoxymethylene (POM) is one of the best engineering plastics which crystallization behavior affects its other properties greatly. In this paper, on the base of discussing the crystallization behavior and its influences, the relationship among the crystallization influence, crystallization behavior and mechanical properties was tried to found. There are several following respects mainly:First, a series of nucleation agents were investigated by polarized optical microscopy (PM) and differential scanning calorimetry (DSC). Avirami and LH equations were employed to analyze the DSC data. The results showed that nucleation agents could speed the crystallization process, minimize the spherulite size, rise up the crystallization peek, decrease interfacial free energies per unit area perpendicular and increase notch impact strength. At the same time the nucleation mechanism was studied. We found that the nucleating process of POM was related with the epitaxy of molecular chain and the nucleation agents changed the crystallization perfection. There are not only physics adsorption, but also chemistry adsorption.Third, The nano-sizes CaCO3 particles were modified with different chemicals and filled into POM, the results showed that the surface treated nano-CaCO3 are able to increase the notched impact strength and the tensile strength. Moreover, it is found that the treated substances have a decisive effect on the surface properties of nano-particles.
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