Electrospun SiO₂ Fiber And Its Application On Toughening Polypropylene

Polypropylene (PP) is widely used in various fields, but there are also disadvantage of poor mechanical properties (such as weak impact properity at low temperature),which limits its application. Thus modified PP has become a focused research.Electrospinning is a fiber spinning technique to prepare polymer fibers sized in diameter from nanometer to micrometer. This paper covered the preparation of two kinds of functional fibers using in modifying PP via electrospinning,as followings.1)This paper presents a preparation of short SiO2 fiber(n-SF) with the diameter of 500 nm via electrospinning combined with sol-gel of TEOS. After short SiO2 fibers treated with silane coupling agent, modified nano-SiO2 fiber/polypropylene (n-MSF/PP) composite was obtained by the extruding and injection. The DSC,XRD and SEM characterization shows that distribution status of SiO2 short fiber in PP matrix is uniform,the interface of short SiO2 fiber and PP matrix is fine, the crystal velocity andβcrystalloid content of n-MSF/PP composite increase compared with that of neat PP; and the analysis on nonisothermal crystallization kinetic shows that heterogeneous nucleation took place with the adding of n-SF in PP, and homogeneous nucleation went with the adding of n-MSF more than 1phr in PP.The impact test shows that the impact property of n-MSF(3phr)/PP composite increases 40.3% than that of pure PP.2)Furthermore,this paper presents a preparation of studded short SiO2 fiber(n-HSF, silica content 0.58%) with the diameter of 500 nm via electrospinning. N-HSF/PP Composite was achieved after the extruding and injection which blended PP and n-HSF. It shows that distribution status of SiO2 short fiber in PP matrix is uniform,the interface of short SiO2 fiber and PP matrix is fine. the crystal velocity andβcrystalloid content of n-HSF/PP composite increase compared with that of neat PP by DSC,XRD and SEM investigation;and the analysis on nonisothermal crystallization kinetic shows that heterogeneous nucleation took place with the adding of n-HSF in PP.The crystalloid of n-HSF/PP Composite decreases in size comparing with pure PP via PLM investigation.The impact test shows that the impact property of n-HSF(0.5phr)/PP composite increases 21.6% than that of pure PP. Short SiO2 fiber with different surface roughness were prepared by changing the silica content of solution,and the analysis on nonisothermal crystallization kinetic shows that homogeneous nucleation took place with the adding of n-HSF(silica content more than 0.84%) in PP, the impact property of n-HSF(2.3%)/PP composite increases 89% than that of pure PP.