Aim To investigate the melting behavior of polyamide 6 in polyamide 6/polyethy lene blends crystallized from amorphous state. Methods DSC was used to test effects of annealing temperature, annealing time, DSC scan rate, and the step wise annealing on the melting peaks of the ice water quenched specimens. Results and Conclusion Varied melting peaks of PA6 component were obtained. The degree of perfection and the crystallization degree of PA6 crystals decreased in the blends, and the crystallization degree of PA6 increased with the increasing of the annealing time. The height of the upper melting peak of reference PA6 is higher than that in blends.
Aim To determine the effect of silane grafted polypropylene on the property of different filler/polypropylene composites. Methods Polypropylene (PP) composites filled with talc(Ta), baryta sulfate and calcium carbonate coupled with silane grafted polypropylene (PP-g-Si) were made, their mechanical properties and thermal properties were investigated, respectively. Results As compared with the non-coupled composites, the mechanical properties of PP/Ta/PP-g-Si composites were improved to some extent, though the values of tensile modulus and the strain at peak were decreased. But for PP/BaSO4 and PP/CaCO3 composites, the values of their mechanical properties varied slightly or even decreased with increasing PP-g-Si content within the experimental component. Meanwhile, PP-g-Si also affected the melting and crystallization behavior of PP in the composites. Conclusion PP-g-Si offers compatibilization in PP/Ta composites, but offers no-compatibilization in PP/BaSO4 and PP/CaCO3 composites within the extent of the present range of PP-g-Si, which shows that PP-g-Si can be used as the macromolecular coupling agent of PP and Ta composite.
