For the production of reactive polyurethane cross-linkinger and curing agents, 2, 4-diisocyanate toluene （TDI） terpolymer, which possesses the rigid structures of hexatomic ring and three reactive functional groups,...For the production of reactive polyurethane cross-linkinger and curing agents, 2, 4-diisocyanate toluene （TDI） terpolymer, which possesses the rigid structures of hexatomic ring and three reactive functional groups, was synthesized and characterized by the Fourier transform infrared （FFIR）, the gel permeation chromatography （GPC） and the chemical analysis methods. The reaction conditions were studied and optimized. A tracking research on the polymerization process of TDI was taken by using the GPC. The formation processes of the terpolymer, oligomers and higher-polymers were also dealt with. Results show that the TDI terpolymer can be prepared in the presence of Cat-3 catalyst and at the reaction temperature of （60 ±2）℃. The reaction time is short, its outcomes have narrow molecular weights distribution, namely molecular weights from 530 to 550, Mw/Mn =1.10, and the mass fraction of NCO is （25. 0 ± 0. 5）%. With the reaction time prolonging, however, TDI can be further higher-polymedzed to form higher-polymers. Benzoyl chloride （0. 4%, mass fraction）, as the stabilizing agent, can effectively inhibit the occurrence of higher-polymerization. The obtained TDI terpolymer can be stable for more than half a year.展开更多
A new type of thermal stabilizer, antimony pent（isooctyl thioglycollate）(Sb(SCH2COOC8H17)5), was synthesized by using antimony trioxide, isooctanol and thioglycolic acid in 2 steps. Firstly, antimony trioxide was ox...A new type of thermal stabilizer, antimony pent（isooctyl thioglycollate）(Sb(SCH2COOC8H17)5), was synthesized by using antimony trioxide, isooctanol and thioglycolic acid in 2 steps. Firstly, antimony trioxide was oxidized into colloidal antimony peroxide. Then antimony peroxide and isooctyl thioglycollate reacted stoichiometrically for 2 h with the yield of 87%. This compound was used as thermal stabilizer for polyvinyl chloride（PVC）. The results show that the thermal stability time is 52min at 200℃ by heat-ageing oven test when adding 2.5% thermal stabilizer to PVC resin. Compared with antimony tris（isooctyl thiolycollate）, the initial thermal stability of antimony pent（isooctyl thioglycollate） is better than that of antimony tris（isooctyl thioglycollate）, while the long-term thermal stability time is shorter than that of antimony tris（isooctyl thioglycollate）. Meanwhile, the synergism of antimony pent（isooctyl thioglycollate） with calcium stearate was studied, indicating that when the mass ratio of antimony pent（isooctyl thioglycollate） to calcium stearate is （2∶1,） the thermal stability time of PVC is 58min.展开更多
文摘For the production of reactive polyurethane cross-linkinger and curing agents, 2, 4-diisocyanate toluene （TDI） terpolymer, which possesses the rigid structures of hexatomic ring and three reactive functional groups, was synthesized and characterized by the Fourier transform infrared （FFIR）, the gel permeation chromatography （GPC） and the chemical analysis methods. The reaction conditions were studied and optimized. A tracking research on the polymerization process of TDI was taken by using the GPC. The formation processes of the terpolymer, oligomers and higher-polymers were also dealt with. Results show that the TDI terpolymer can be prepared in the presence of Cat-3 catalyst and at the reaction temperature of （60 ±2）℃. The reaction time is short, its outcomes have narrow molecular weights distribution, namely molecular weights from 530 to 550, Mw/Mn =1.10, and the mass fraction of NCO is （25. 0 ± 0. 5）%. With the reaction time prolonging, however, TDI can be further higher-polymedzed to form higher-polymers. Benzoyl chloride （0. 4%, mass fraction）, as the stabilizing agent, can effectively inhibit the occurrence of higher-polymerization. The obtained TDI terpolymer can be stable for more than half a year.
基金Project supported by the Postdoctoral Foundation of Central South University
文摘A new type of thermal stabilizer, antimony pent（isooctyl thioglycollate）(Sb(SCH2COOC8H17)5), was synthesized by using antimony trioxide, isooctanol and thioglycolic acid in 2 steps. Firstly, antimony trioxide was oxidized into colloidal antimony peroxide. Then antimony peroxide and isooctyl thioglycollate reacted stoichiometrically for 2 h with the yield of 87%. This compound was used as thermal stabilizer for polyvinyl chloride（PVC）. The results show that the thermal stability time is 52min at 200℃ by heat-ageing oven test when adding 2.5% thermal stabilizer to PVC resin. Compared with antimony tris（isooctyl thiolycollate）, the initial thermal stability of antimony pent（isooctyl thioglycollate） is better than that of antimony tris（isooctyl thioglycollate）, while the long-term thermal stability time is shorter than that of antimony tris（isooctyl thioglycollate）. Meanwhile, the synergism of antimony pent（isooctyl thioglycollate） with calcium stearate was studied, indicating that when the mass ratio of antimony pent（isooctyl thioglycollate） to calcium stearate is （2∶1,） the thermal stability time of PVC is 58min.
