Theoretical and empirical models for predicting the thermal conductivity of polymer composites were summarized since the 1920s.The effects of particle shape,filler amount,dispersion state of fillers,and interfacial th...Theoretical and empirical models for predicting the thermal conductivity of polymer composites were summarized since the 1920s.The effects of particle shape,filler amount,dispersion state of fillers,and interfacial thermal barrier on the thermal conductivity of filled polymer composites were investigated,and the agreement of experimental data with theoretical models in literatures was discussed.Silica with high thermal conductivity was chosen to mix with polyvinyl-acetate （EVA） copolymer to prepare SiO2/EVA co-films.Experimental data of the co-films＇ thermal conductivity were compared with some classical theoretical and empirical models.The results show that Agari＇s model,the mixed model,and the percolation model can predict well the thermal conductivity of SiO2/EVA co-films.展开更多
Dynamic rheological characteristics of polypropylene (PP) filled with ultra-fine full-vulcanized powdered rubber (UFPR) composed of styrene-butadiene copolymer were studied through dynamic rheological measurements on ...Dynamic rheological characteristics of polypropylene (PP) filled with ultra-fine full-vulcanized powdered rubber (UFPR) composed of styrene-butadiene copolymer were studied through dynamic rheological measurements on an Advanced Rheometric Expansion System (ARES). A specific viscoelastic phenomenon, i.e. 'the second plateau', appeared at low frequencies, and exhibits a certain dependence on the amount of rubber particles and the dispersion state in the matrix. This phenomenon is attributed to the formation of aggregation structure of rubber particles. The analyses of Cole-Cole diagrams of the dynamic viscoelastic functions suggest that the heterogeneity of the composites is enhanced on increasing both particle content and temperature.展开更多
Vacuum-assisted spin-coating is an effective polymer filling technology for sidewall insulating of through-silicon-via(TSV).This paper investigated the flow mechanism of the vacuum-assisted polymer filling process bas...Vacuum-assisted spin-coating is an effective polymer filling technology for sidewall insulating of through-silicon-via(TSV).This paper investigated the flow mechanism of the vacuum-assisted polymer filling process based on experiments and numerical simulation,and studied the effect of vacuum pressure,viscosity of polymer and aspect-ratio of trench on the filling performance.A 2D axisymmetric model,consisting of polymer partially filled into the trench and void at the bottom of trench,was developed for the computational fluid dynamics(CFD)simulation.The simulation results indicate that the vacuum-assisted polymer filling process goes through four stages,including bubble formation,bubble burst,air elimination and polymer re-filling.Moreover,the simulation results suggest that the pressure significantly affects the bubble formation and the polymer re-filling procedure,and the polymer viscosity and the trench aspect-ratio influence the duration of air elimination.展开更多
基金supported by the High-Tech Research and Development Program of China (863 Program) (No.2006AA050203)
文摘Theoretical and empirical models for predicting the thermal conductivity of polymer composites were summarized since the 1920s.The effects of particle shape,filler amount,dispersion state of fillers,and interfacial thermal barrier on the thermal conductivity of filled polymer composites were investigated,and the agreement of experimental data with theoretical models in literatures was discussed.Silica with high thermal conductivity was chosen to mix with polyvinyl-acetate （EVA） copolymer to prepare SiO2/EVA co-films.Experimental data of the co-films＇ thermal conductivity were compared with some classical theoretical and empirical models.The results show that Agari＇s model,the mixed model,and the percolation model can predict well the thermal conductivity of SiO2/EVA co-films.
基金This work was supported by the National Science Fund for Distinguished Young Scholars of China (No.50125312) andSpecial Funds for Major State Basic Research Projects (No.G1999064800).
文摘Dynamic rheological characteristics of polypropylene (PP) filled with ultra-fine full-vulcanized powdered rubber (UFPR) composed of styrene-butadiene copolymer were studied through dynamic rheological measurements on an Advanced Rheometric Expansion System (ARES). A specific viscoelastic phenomenon, i.e. 'the second plateau', appeared at low frequencies, and exhibits a certain dependence on the amount of rubber particles and the dispersion state in the matrix. This phenomenon is attributed to the formation of aggregation structure of rubber particles. The analyses of Cole-Cole diagrams of the dynamic viscoelastic functions suggest that the heterogeneity of the composites is enhanced on increasing both particle content and temperature.
文摘Vacuum-assisted spin-coating is an effective polymer filling technology for sidewall insulating of through-silicon-via(TSV).This paper investigated the flow mechanism of the vacuum-assisted polymer filling process based on experiments and numerical simulation,and studied the effect of vacuum pressure,viscosity of polymer and aspect-ratio of trench on the filling performance.A 2D axisymmetric model,consisting of polymer partially filled into the trench and void at the bottom of trench,was developed for the computational fluid dynamics(CFD)simulation.The simulation results indicate that the vacuum-assisted polymer filling process goes through four stages,including bubble formation,bubble burst,air elimination and polymer re-filling.Moreover,the simulation results suggest that the pressure significantly affects the bubble formation and the polymer re-filling procedure,and the polymer viscosity and the trench aspect-ratio influence the duration of air elimination.
