writer：Heming LIN, Dongming QI*, Jian HAN, Zhiqi CAI, Minghua WU
keywords：rigid organic filler, polypropylene, impact resistance
source：期刊
specific source：Front. Chem. Eng. China, 3(2): 176-181
Issue time：2009年

A novel phenolic rigid organic filler (KT) was used to modify isotactic polypropylene (iPP). The influence of KT particles on the impact resistance property of PP/KT specimens (with similar interparticles distance, 1.8 μm) was studied by notched izod impact tests. It was found the brittle-ductile transition (BDT) of the PP/KT microcomposites took place at the filler content of about 4%, and the impact strength attains the maximum at 5% (with filler particles size of 1.5 μm), which is about 2.5 times that of unfilled iPP specimens. The impact fracture morphology was investigated by scanning electron microscopy (SEM). For the PP/KT specimens and the high-density polyethylene/KT (HDPE/KT) specimens in ductile mode, many micro-fibers could be found on the whole impact fracture surface. It is the filler particles that induced the plastic deformation of interparticles ligament and hence improved the capability of iPP matrix on absorbing impact energy dramatically. The determinants on the BDT were further discussed on the basis of stress concentration and debonding resistance. It can be concluded that not only the interparticle distance but also the filler particles size play an important role in semi-crystalline polymer toughening.