Studies On Preparation And Properties Of Rigidity-toughness Balanced Polypropylene Composites

In this paper,calcium carbonate?CaCO₃?whisker and nano-silicon?Si?grafted polycaprolactone?PCL?composited particles?Si-g-PCL?were used as reinforcing agents,glycidyl methacrylate grafted ethylene-octene copolymer?POE-g-GMA?as toughening agent,which were added into polypropylene?PP?matrix in order to obtaincomposite materials with rigidity-toughness balance.The main results are as follows.?1?CaCO₃ whiskers were surface-treated with traditional coupling agent,such as stearic acid,titanate and aluminate,which were used to modify PP.The results of mechanical properties,scanning electron microscopy?SEM?,thermogravimetric analysis?TGA?and X-ray diffraction?XRD?measurements showt hat the tensile strength and impact properties of PP were improved moderately by CaCO₃ whisker,and the surface treatment effect of aluminate on CaCO₃ whisker was the best.?2?Two kinds of functional ionic liquids,1-butyl-3-methylimidazole bisulfate?LSQIL?,1-butyl-3-methylimidazole methanesulfonate?HSQIL?,and silane ionic liquids?GWIL?synthesized in laboratory was used to treat CaCO₃ whiskers,respectivly.Then the treated whiskers were melt blended with PP.GWIL was characterized by Fourier transform infrared spectrometer?FT-IR?.The results indicate that CaCO₃ whiskers treated by GWIL could improve the mechanical properties of PP more significantly.Moreover,GWIL improved the dispersion of CaCO₃ whiskers treated by in PP matrix and its compatibility with PP.?3?Aluminate and GWIL were used to treat CaCO₃ whiskers,which was used to melt-blended with POE-g-GMA and PP,respectively.The results of mechanical propertie,TGA,differential scanning caloirmeter?DSC?,SEM meausrements show that,the treating effect of GWIL was superior to that of aluminate.Moreover,the addition of POE-g-GMA made the tensile properties of PP/CaCO₃ whisker binary composites not decline,but the toughness of the composites improve obviously,which achieved rigidity-toughness balance of PP.?4?PP was modified by blending nanoSi-g-PCL composited particles prepared in the laboratory and POE-g-GMA.Relevant test results show that the modification effect of nano-Si-g-PCL composited particles was better than that of PCL and nano-si particles alone,which could simultaneously reinforce and toughen PP,achieving good rigidity-toughness balance.