چكيده به لاتين
Many researches have shown that adding boron nitride to epoxy matrices increases its physical-mechanical properties. In order for a nanoparticle to perform properly, it is necessary to use its maximum specific surface capacity which is created in nano the materials nano dimention. For this purpose, if a nanoparticle is layered, these layers must be separated. In this project, boron nitride exfoliation was performed using HEMA monomer polymerization between plates and its success was confirmed by XRD, AFM, FTIR, RAMAN and FE-SEM analyzes. However, Boron Nitride has a tendency to create cluster and this causes not to achieve uniform distribution in the matrix. In this research, surface modification of boron nitride was achieved by two methods: washing with sodium hydroxide and with the help of silane epoxide coupling agent (GLYEO). Also, the effect of the concentration of silane agents in the aqueous solution during the surface modification reaction was evaluated. Finally, the performance of epoxy nanocomposites without nanoparticles, containing raw boron nitride, exfoliated boron nitride and modified silanized boron nitride was compared. Modified boron nitrides were analyzed by FTIR, FE-SEM and TGA. Epoxy nanocomposites containing boron nitride and surface modified boron nitrides were also investigated by tensile and flexual mechanical tests and DSC, DMTA, FE-SEM analyzes. The results showed that the silane groups were successfully attached to the boron nitride surface. The tensile strength of the sample containing exfoliated nanoparticles and modified with silane decreased by 9 and 14%, respectively, and the tensile modulus compared to pure epoxy increased by 6 and 2%, respectively. The flexual strength for the sample containing exfoliated nanoparticles and modified with silane decreased by 10% and 6%, respectively, and the flexual modulus increased by 20% and 9%, respectively. Also, the storage modulus of nanocomposites containing exfoliated boron nitride and silane decreased by 33% and increased by 23% compared to pure epoxy, respectively, and the glass transition temperature for nanocomposites containing exfoliated boron nitride and silane increased by 4 and 15 degrees, respectively. According to DSC analysis, the curing of nanocomposites containing exfoliated and silanized nanoparticles decreased and the heat resulting from their curing decreased by 20 and 28% respectively compared to pure epoxy, and the curing temperature also increased to some extent, which confirms the better interaction of silane nanoparticles with polymer.