Molecular Dynamics Simulation of Physical Properties of Silicon Modified Phenolic Resin
The physical properties of modified nano-SiO2 and methyl-phenyl-dimethoxy-silane modified phenolic resin are studied by molecular dynamics simulation.The results show that the glass transition temperature of unmodified phenolic resin at 300 K is 362 K,the elastic modulus and shear modulus are 5.45 GPa and 2.19 GPa,the thermal conductivity and thermal expansion coefficients are 0.37 W·(m·k)-1 and 3.8 × 10-5K-1,respectively.The addition of nano-SiO2 increases the glass transition temperature by 1.6％,the elastic modulus and shear modulus by 34.9％and 28.8％,and the thermal conductivity and thermal expansion by 11％and 31.6％,respectively.The thermal conductivity and thermal expansion are reduced by 11％and 31.6％,respectively.SiO2 surface grafting 3％,5％,7％and 10％silane coupling agent and methyl-phenyl-dimethoxy-silane modified phenolic resin,the glass transition temperature increased by 10.5％,15.2％,16.8％,19.3％and 1.5％respectively,the elastic modulus increased by 44.4％,53.2％,53.8％,63.5％and 13.4％respectively,and the thermal conductivity decreased by 12.4％,13.5％,11.2％,7％and 10％respectively.Moreover,the thermal expansion coefficient of phenol formaldehyde resin modified by methyl phenyl dimethoxy silane increased by 51.8％compared with the unmodified phenol formaldehyde resin.The study show that the doping of nano-SiO2,the grafting of silane coupling agent on the SiO2 surface,and the modification of methyl-phenyl-dimethoxy-silane can improve the glass transition temperature,and mechanical properties and reduce the thermal conductivity of phenolic resin.Only nano-SiO2 doping can reduce the thermal expansion coefficient,whereas the modification of methyl-phenyl-dimethoxy-silane will increase substantially.
NETL
NSTL
万方数据
