Silane coupling agents modified glass micro-balloons for unsaturated polyester resin

Two kinds of hollow and porous glass micro-balloons were modified for unsaturated polyester resin(UPR) composites by three types of silane coupling agents containing vinyl,methacrylato group and expoy group,respectively.The modification mechanism was investigated by FTIR,1H-NMR,SEM and mechanical property tests.The results showed that the body structures of micro-balloon and the unsaturated polyester resin matrix were not changed by silane coupling agents.The surface tension of micro-balloon was increased by the C==C group in the non-polar end of the silane coupling agent which was similar to the C==C group of UPR and easily combined with UPR.Furthermore,the interlayer between micro-balloon and UPR was flexible because of the long chain in the non-polar end of the silane coupling agent.For the silane coupling agents with the same non-polar end,the combination between coupling agent with a large polar end and micro-balloon was weak.The uniform shape of the micro-balloon was benificial for the combination of micro-balloon with UPR.