Polymer processing
Jun Huang; Guanghua Tian; Huayi Li; Lei Li; Qian Li; He Huang; Shuirong Zheng; Youliang Hu
Abstract
In this work, a series of polypropylene/polyvinyl butyral (PP/PVB) blends were prepared by melt-blending process, at PVB loadings 3 wt%, 10 wt%, and 30 wt%. The effects of PVB on crystallization behavior of PP were investigated by differential scanning calorimetry (DSC), and polarized optical ...
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In this work, a series of polypropylene/polyvinyl butyral (PP/PVB) blends were prepared by melt-blending process, at PVB loadings 3 wt%, 10 wt%, and 30 wt%. The effects of PVB on crystallization behavior of PP were investigated by differential scanning calorimetry (DSC), and polarized optical microscopy (POM). The isothermal crystallization kinetics were analyzed by Avrami equations. It was found that the addition of PVB strikingly reduced the overall crystallization rate of PP. The POM results further indicated that the crystallization rate of PP/PVB was significantly reduced by reducing the nucleation density of PP with the addition of PVB. The fractured surface morphology of PP/PVB blends was characterized by scanning electron microscopy (SEM), and the results showed that the PVB was uniformly dispersed in the PP matrix as small spherical particles, with a good dispersion and dimensional stability.
Structure and property relationship
Qian Li; Yongjie Zhang; Huayi Li; Zhongchuan Peng; Yu Zhang; Youliang Hu
Abstract
PP-g-PS copolymer is a typical compatilizer used in polypropylene and polystyrene immiscible blends. PP-g-PS copolymers with different side chain lengths were synthesized, and their thermal and mechanical properties were characterized by differential scanning calorimetry (DSC), polarizing optical microscopy ...
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PP-g-PS copolymer is a typical compatilizer used in polypropylene and polystyrene immiscible blends. PP-g-PS copolymers with different side chain lengths were synthesized, and their thermal and mechanical properties were characterized by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and dynamic mechanical analysis (DMA), respectively. The DSC and POM results show that the introduction of PS side chain dramatically accelerates the crystallization rate of the PP main chain due to the covalent bond in the PP and PS copolymer. Furthermore, the copolymers become more rigid as the PS component content increases. Blend of PP with PP-g-PS copolymer was prepared to investigate the compatibility between PP and PS. The properties of five PP/PP-g-PS binary blends were characterized by DSC, DMA, scanning electron microscopy (SEM) and mechanical testing. Well dispersion of PS and small PS particle size are detected in the binary blends. The formation of covalent bond between PP and PS also increases the compatibility and interfacial adhesion between these two phases.
Characterization
Tao Zheng; Qian Li; Qian Zhou; Huayi Li; Qian Xing; Liaoyun Zhang; Youliang Hu
Abstract
9,10-Dihydro-9,10-ethano-anthracene-11,12-dicarboxylic acid disodium salt (DHEAS) was synthesized and used as a nucleating agent for poly(1-butene) (iPB). The isothermal crystallization kinetics of iPB having different nucleating agents were investigated by differential scanning calorimetry (DSC) and ...
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9,10-Dihydro-9,10-ethano-anthracene-11,12-dicarboxylic acid disodium salt (DHEAS) was synthesized and used as a nucleating agent for poly(1-butene) (iPB). The isothermal crystallization kinetics of iPB having different nucleating agents were investigated by differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The results showed that the nucleating agents increased the crystallization temperature and the crystallization rate and shortened the crystallization half-time (t1/2). As well, the nucleating agents could be used as heterogeneous nuclei in the iPB matrix and decreased the size of iPB. When the nucleating agent was DHEAS, the crystallization temperature of iPB was up to 93.6°C which was higher than that of other nucleating agents for iPB and pure iPB. The crystallization half-time in the presence of DHEAS was 0.58 min which was less than that of other nucleating agents for iPB and pure iPB. In this case, the spherulitic size of iPB was the smallest and the morphology was changed, which indicated that DHEAS displayed better nucleation effect among the studied nucleating agents.
