The objectives of this paper are to understand the crystallization behavior of polypropylene （PP） composites with surface modified tetra-needle-shaped zinc oxide whisker （T-ZnOw）. T-ZnOw was surface modified with ...The objectives of this paper are to understand the crystallization behavior of polypropylene （PP） composites with surface modified tetra-needle-shaped zinc oxide whisker （T-ZnOw）. T-ZnOw was surface modified with different coupling agents, such as silane coupling agents （KH-550, KH-560） and titanate coupling agent （NDZ-105）, in order to improve the compatibility between PP and T-ZnOw. DSC and POM were used to characterize the melt and crystallization behavior and the crystalline structures of the composites, respectively. The results show that the surface modified T-ZnOw acts as a nucleating agent of PP crystallization, depending on the coupling agent used for modification. KH-550 and KH-560 have more apparent role in improving the interfacial interaction than NDZ-105 and induce PP crystallization at higher temperature and with smaller spherulites size. The results also suggest that the crystallization behavior depends on not only the content of coupling agent, but also the content of the surface modified T-ZnOw used in the composites.展开更多
As a part of serial work about the application of a tetra-needle-shaped whisker(T-ZnOw) with a spatial structure in polymer composites,this work is focused on the effect of T-ZnOw dimension on the properties of polyme...As a part of serial work about the application of a tetra-needle-shaped whisker(T-ZnOw) with a spatial structure in polymer composites,this work is focused on the effect of T-ZnOw dimension on the properties of polymer composites. Two kinds of T-ZnOw whiskers with different dimensions(big and small one) are introduced into PA6 composites.Our results show that for the big whisker and the small whisker both,the addition of T-ZnOw induces the mechanical property improvement of T-ZnOw/PA6 composites.Especially,...展开更多
The main subject of this work is about the effect of T-ZnOw on the toughness and stiffness of polystyrene (PS).In order to avoid the rupture of T-ZnOw during the melt processing,T-ZnOw/PS composites were obtained via ...The main subject of this work is about the effect of T-ZnOw on the toughness and stiffness of polystyrene (PS).In order to avoid the rupture of T-ZnOw during the melt processing,T-ZnOw/PS composites were obtained via the combination of solution blending and injection moulding methods.Although the tensile strength of the composites decreases slightly,the impact strength and tensile modulus increase with the increase of the T-ZnOw content in the matrix.The stiffness and toughness of the composites are enhance...展开更多
A novel three-dimensional lattice model of tetrapod-like zinc oxide whisker（T-ZnOw） resin matrix composite with a coordination number of 12 is constructed based on the special structure of T-ZnOw;the percolation phe...A novel three-dimensional lattice model of tetrapod-like zinc oxide whisker（T-ZnOw） resin matrix composite with a coordination number of 12 is constructed based on the special structure of T-ZnOw;the percolation phenomenon of the system is simulated by the Monte Carlo method,and the percolation threshold is obtained at 23.2%.The critical mixing ratio of T-ZnOw is calculated by considering the practical factors,and the result basically agrees with the reported one.Theoretical calculation shows that the critical mixing ratio mainly depends on the L/D ratio of T-ZnOw, and is also related to the size of T-ZnOw as well as the preparation method of the composite.The microwave absorbing mechanism of T-ZnOw composite is discussed,and conductivity loss and point discharge caused by the polarization effect are regarded to be two important means of energy dissipation.展开更多
基金This work was supported by the National Natural Science Foundation of China(Youth Foundation:50403019)partly supported by the Opening Project of State Key Laboratory of Polymer Materials Engineering(Sichuan University).
文摘The objectives of this paper are to understand the crystallization behavior of polypropylene （PP） composites with surface modified tetra-needle-shaped zinc oxide whisker （T-ZnOw）. T-ZnOw was surface modified with different coupling agents, such as silane coupling agents （KH-550, KH-560） and titanate coupling agent （NDZ-105）, in order to improve the compatibility between PP and T-ZnOw. DSC and POM were used to characterize the melt and crystallization behavior and the crystalline structures of the composites, respectively. The results show that the surface modified T-ZnOw acts as a nucleating agent of PP crystallization, depending on the coupling agent used for modification. KH-550 and KH-560 have more apparent role in improving the interfacial interaction than NDZ-105 and induce PP crystallization at higher temperature and with smaller spherulites size. The results also suggest that the crystallization behavior depends on not only the content of coupling agent, but also the content of the surface modified T-ZnOw used in the composites.
基金supported by the National Natural Science Foundation of China(No50403019)Sichuan Youthful Science and Technology Foundation of China(No07ZQ026-003)
文摘As a part of serial work about the application of a tetra-needle-shaped whisker(T-ZnOw) with a spatial structure in polymer composites,this work is focused on the effect of T-ZnOw dimension on the properties of polymer composites. Two kinds of T-ZnOw whiskers with different dimensions(big and small one) are introduced into PA6 composites.Our results show that for the big whisker and the small whisker both,the addition of T-ZnOw induces the mechanical property improvement of T-ZnOw/PA6 composites.Especially,...
基金the National Natural Science Foundation of China (No.50403019)also partly supported by the Opening Project of State Key Laboratory of Polymer Materials Engineering (Sichuan University).
文摘The main subject of this work is about the effect of T-ZnOw on the toughness and stiffness of polystyrene (PS).In order to avoid the rupture of T-ZnOw during the melt processing,T-ZnOw/PS composites were obtained via the combination of solution blending and injection moulding methods.Although the tensile strength of the composites decreases slightly,the impact strength and tensile modulus increase with the increase of the T-ZnOw content in the matrix.The stiffness and toughness of the composites are enhance...
基金supported by the Knowledge Innovation Engineering of the Chinese Academy of Sciences(No.YYYJ-0701-02)the National Natural Science Foundation of China(Nos.60890193,60606002,60906006)+1 种基金the State Key Development Program for Basic Research of China(Nos.2006CB604905,2010CB327503)the Knowledge Innovation Program of the Chinese Academy of Sciences(Nos. ISCAS2008T01,ISCAS2009L02).
文摘A novel three-dimensional lattice model of tetrapod-like zinc oxide whisker（T-ZnOw） resin matrix composite with a coordination number of 12 is constructed based on the special structure of T-ZnOw;the percolation phenomenon of the system is simulated by the Monte Carlo method,and the percolation threshold is obtained at 23.2%.The critical mixing ratio of T-ZnOw is calculated by considering the practical factors,and the result basically agrees with the reported one.Theoretical calculation shows that the critical mixing ratio mainly depends on the L/D ratio of T-ZnOw, and is also related to the size of T-ZnOw as well as the preparation method of the composite.The microwave absorbing mechanism of T-ZnOw composite is discussed,and conductivity loss and point discharge caused by the polarization effect are regarded to be two important means of energy dissipation.
