有机蒙脱土对PA6/PP合金体系的作用机制及其对材料性能的影响

研究了有机蒙脱土对PA6/PP合金体系的作用机制及其对材料性能的影响。结果表明,OMMT的添加可以提高体系的拉伸强度、弯曲强度和弯曲模量,但冲击强度会有某种程度的下降;OMMT主要分散在PA6连续相中,且当其添加量质量份数低于5%时,可以在PA6相中实现较充分的剥离;OMMT对PA6/PP合金体系有着显著的增容作用,这可能和片层对PP分散相凝聚时的阻隔,以及片层所起到的类似接枝物的增容作用有关;OMMT在PA6基体中被充分剥离后,将有利于使复合体系的拉伸强度、弯曲强度得到提高,但OMMT片层及和片层有关的类似接枝物的存在,将束缚并限制界面层附近PP相的屈服,而使材料冲击韧性下降。

Mechanism and Effects of Organo-montmorillonite on the Mechanical Properties of PA6/PP Alloy

The mechanism and effects of organo-montmorillonite(OMMT) on PA6/PP alloy were investigated.The addition of OMMT improved the tensile strength,flexural strength and flexural modulus of the alloy,however,the impact strength decreased to a certain extent.OMMT was mainly dispersed in the PA6 matrix.When OMMT content was no more than 5wt%,most OMMT was exfoliated in the PA6 matrix.OMMT greatly improved the compatibility of the PA6/PP blends.The compatiblization effect of OMMT may be described that the exfoliate clay platelets in the PA6 matrix effectively prevented the coalescence of PP dispersed domains.It also may be explained that the exfoliated clay platelets acted as the compatiblization of the grafted polymer. The exfoliated clay platelets made for the improvement of tensile strength and flexural strength of the blends. On the contrary,the existence of the clay platelets and the similar grafted polymer related with the clay platelets limited the yield of PP phase round the interface and decreased the impact strength.