Grignard reagents were prepared from the starting materials 1-bromo-3,5-difluorobenzene,1-bromo-2,4-difluorobenzene andbromo-3,4-difluorobenzene respectively,then reacted with diethyl carbonate to form magnesium tris(...Grignard reagents were prepared from the starting materials 1-bromo-3,5-difluorobenzene,1-bromo-2,4-difluorobenzene andbromo-3,4-difluorobenzene respectively,then reacted with diethyl carbonate to form magnesium tris(difluoropheny)methanol,and methacryloyl chloride was added dropwise to abtain tris(difluorophenyl)methyl methacrylates.The target products were synthesized in high overall yield(67～74%)with"one-pot"method.Structures of the compounds were comfirmed by IR,1HNMR,13CNMR and elemental analysis,and methanolysis was also studied.展开更多
The microstructures of the hybrid core-shell latex synthesized by emulsion copolymerization of 3-trimethoxysilyl propyl methacrylate（MPS） and styrene were investigated.The polymers obtained under different operating...The microstructures of the hybrid core-shell latex synthesized by emulsion copolymerization of 3-trimethoxysilyl propyl methacrylate（MPS） and styrene were investigated.The polymers obtained under different operating conditions were characterized by（）29Si solid state NMR,FTIR,DSC and elemental analysis.It was found that under a neutral condition all of the MPS monomers were copolymerized into the polymer chain,small part of SiOR groups were hydrolyzed into SiOH groups and crosslinked by hydrogen bonds,the content of crosslinking is increased by MPS addition amount.Under basic condition,part of MPS were hydrolyzed and condensed into oligomers firstly,then these resultants were grafted into the polymer chain as pendent chain by both free radical polymerization and hydrolysis-condensation reaction.And under acidic condition,MPS in the system was easily hydrolyized and acted as crosslinker so that the emulsion became gels rapidly.展开更多
文摘Grignard reagents were prepared from the starting materials 1-bromo-3,5-difluorobenzene,1-bromo-2,4-difluorobenzene andbromo-3,4-difluorobenzene respectively,then reacted with diethyl carbonate to form magnesium tris(difluoropheny)methanol,and methacryloyl chloride was added dropwise to abtain tris(difluorophenyl)methyl methacrylates.The target products were synthesized in high overall yield(67～74%)with"one-pot"method.Structures of the compounds were comfirmed by IR,1HNMR,13CNMR and elemental analysis,and methanolysis was also studied.
文摘The microstructures of the hybrid core-shell latex synthesized by emulsion copolymerization of 3-trimethoxysilyl propyl methacrylate（MPS） and styrene were investigated.The polymers obtained under different operating conditions were characterized by（）29Si solid state NMR,FTIR,DSC and elemental analysis.It was found that under a neutral condition all of the MPS monomers were copolymerized into the polymer chain,small part of SiOR groups were hydrolyzed into SiOH groups and crosslinked by hydrogen bonds,the content of crosslinking is increased by MPS addition amount.Under basic condition,part of MPS were hydrolyzed and condensed into oligomers firstly,then these resultants were grafted into the polymer chain as pendent chain by both free radical polymerization and hydrolysis-condensation reaction.And under acidic condition,MPS in the system was easily hydrolyized and acted as crosslinker so that the emulsion became gels rapidly.
