A novel thermosetting resin system for superabrasives based on novolak and bismaleimide (BMI) was developed. The novolak resin was allylated and then copolymerized with BMI. The structure of allyl novolak and reacti...A novel thermosetting resin system for superabrasives based on novolak and bismaleimide (BMI) was developed. The novolak resin was allylated and then copolymerized with BMI. The structure of allyl novolak and reaction mechanism were analyzed by FFIR. Thermal and mechanical properties were characterized by using com- prehensive thermal analyzer (DSC-TG) and strength tester, respectively. The results showed that high molecular weight of novolak was advantageous for heat-resistance, but was unfavorable for the bending strength. High allyl content improved the heat-resistance but lowered the bending strength. When the molecular weight of novolak was 450 and allyl content was 50%, the best resin system with good heat-resistance and bending strength was obtained. It was suitable for the manufacturing of superabrasive tools.展开更多
The rheological behavior of bismaleimide resin for resin transfer molding(RTM) was studied with DSC analysis and viscosity experiments A rheological model based on the dual Arrhenius equation was established and used ...The rheological behavior of bismaleimide resin for resin transfer molding(RTM) was studied with DSC analysis and viscosity experiments A rheological model based on the dual Arrhenius equation was established and used to simulate the rheological behavior of the resin The model predictions determined from the dual Arrhenius equation were in good agreement with experimental data The processing window of the resin system can be well determined based on the developed model The rheological model is importan...展开更多
A copolymer of bismaleimide-diallylbisphenol A-diphenylsilandiol was synthesized and the copolymerisation was studied by using N-phenylmaleimide, bisphenol A and diphenyl-silandiol as model compounds. The copolymer co...A copolymer of bismaleimide-diallylbisphenol A-diphenylsilandiol was synthesized and the copolymerisation was studied by using N-phenylmaleimide, bisphenol A and diphenyl-silandiol as model compounds. The copolymer could be well. cured around 200 degrees C, and the cured resins had good thermal stability. In the range of 170-210 degrees C, a higher curing temperature was favorable to obtain more thermal stable resin by reducing the content of diphenylsilandiol cyclo-homopolymer in resin which would spoil its-thermal stability.展开更多
The curing proces of chemical reactombetween flexible unsaturated polymer resin and diphenyl-methane bismaleimides which have been chain-prolonged by diaminodiphenylmethane is presented. also the kinetics parameter...The curing proces of chemical reactombetween flexible unsaturated polymer resin and diphenyl-methane bismaleimides which have been chain-prolonged by diaminodiphenylmethane is presented. also the kinetics parameters and curing technology are investigated.展开更多
2,2'-Bis (4H-3,1-benaoxazin-4-one) (BBON) has been proved to be an effective chain extender for poly (ethylene terephthalate) (PET). In order to study the reaction mechanism and kinetics of chain-extending reactio...2,2'-Bis (4H-3,1-benaoxazin-4-one) (BBON) has been proved to be an effective chain extender for poly (ethylene terephthalate) (PET). In order to study the reaction mechanism and kinetics of chain-extending reaction, beta-bishydroxyethylene terephthalate (BHET) was selected as model compound. The NMR data, IR spectra and number average molecular weight (<(M)over bar (n)>) of the products obtained from the reaction of BBON and BHET verify that BBON is a hydroxyl-reactive extender. The mechanism was discussed. Kinetics data indicate that extending reaction is a second order reaction, and BBON has high reactivity. The activation energy (E(a)) was measured.展开更多
文摘A novel thermosetting resin system for superabrasives based on novolak and bismaleimide (BMI) was developed. The novolak resin was allylated and then copolymerized with BMI. The structure of allyl novolak and reaction mechanism were analyzed by FFIR. Thermal and mechanical properties were characterized by using com- prehensive thermal analyzer (DSC-TG) and strength tester, respectively. The results showed that high molecular weight of novolak was advantageous for heat-resistance, but was unfavorable for the bending strength. High allyl content improved the heat-resistance but lowered the bending strength. When the molecular weight of novolak was 450 and allyl content was 50%, the best resin system with good heat-resistance and bending strength was obtained. It was suitable for the manufacturing of superabrasive tools.
基金National Natural Science F oundation of China(5 983 3 110 ) National Defence Foundation(0 0 j0 0 .5 .3 .hk0 14 4)
文摘The rheological behavior of bismaleimide resin for resin transfer molding(RTM) was studied with DSC analysis and viscosity experiments A rheological model based on the dual Arrhenius equation was established and used to simulate the rheological behavior of the resin The model predictions determined from the dual Arrhenius equation were in good agreement with experimental data The processing window of the resin system can be well determined based on the developed model The rheological model is importan...
文摘A copolymer of bismaleimide-diallylbisphenol A-diphenylsilandiol was synthesized and the copolymerisation was studied by using N-phenylmaleimide, bisphenol A and diphenyl-silandiol as model compounds. The copolymer could be well. cured around 200 degrees C, and the cured resins had good thermal stability. In the range of 170-210 degrees C, a higher curing temperature was favorable to obtain more thermal stable resin by reducing the content of diphenylsilandiol cyclo-homopolymer in resin which would spoil its-thermal stability.
文摘The curing proces of chemical reactombetween flexible unsaturated polymer resin and diphenyl-methane bismaleimides which have been chain-prolonged by diaminodiphenylmethane is presented. also the kinetics parameters and curing technology are investigated.
文摘2,2'-Bis (4H-3,1-benaoxazin-4-one) (BBON) has been proved to be an effective chain extender for poly (ethylene terephthalate) (PET). In order to study the reaction mechanism and kinetics of chain-extending reaction, beta-bishydroxyethylene terephthalate (BHET) was selected as model compound. The NMR data, IR spectra and number average molecular weight (<(M)over bar (n)>) of the products obtained from the reaction of BBON and BHET verify that BBON is a hydroxyl-reactive extender. The mechanism was discussed. Kinetics data indicate that extending reaction is a second order reaction, and BBON has high reactivity. The activation energy (E(a)) was measured.