The hydroxyl-terminated polybutadiene （HTPB） possessing high content of 1,4-units was synthesized by anionic polymerization of butadiene, using alkyllithium containing silicon-protected hydroxyl group as initiator a...The hydroxyl-terminated polybutadiene （HTPB） possessing high content of 1,4-units was synthesized by anionic polymerization of butadiene, using alkyllithium containing silicon-protected hydroxyl group as initiator and cyclohexane as solvent. The polymers were characterized by GPC, IR and 1H-NMR. The mechanical properties of cured films were also evaluated. The results show that the content of 1,4-units for HTPBs made by anionic polymerization reaches up to 90%. The molecular weight distribution is very narrow （〈 1.05）. The functionality of hydroxyl groups approaches 2. Compared with free radical HTPB, the elongation at break of anionic HTPB films increased by 70%, while the tensile strength remained nearly unchanged. This new HTPB can be very useful in solid propellant.展开更多
以异戊二烯(Ip)为单体,Al(i-Bu)3(简称Al)/TiCi4(简称Ti)为催化剂(以100 g Ip计,Al、Ti的用量分别为2.27～3.77 mmol、4.08～6.81 mmol),芳香醚为活化剂,合成了异戊二烯橡胶(IR),考察合成钛系IR的影响因素,并将合成的钛系IR与日本Zeon...以异戊二烯(Ip)为单体,Al(i-Bu)3(简称Al)/TiCi4(简称Ti)为催化剂(以100 g Ip计,Al、Ti的用量分别为2.27～3.77 mmol、4.08～6.81 mmol),芳香醚为活化剂,合成了异戊二烯橡胶(IR),考察合成钛系IR的影响因素,并将合成的钛系IR与日本Zeon公司生产的钛系IR的性能进行对比。结果表明,采用Al/Ti/芳香醚体系,可合成出顺式-1,4-结构质量分数大于97.00%的IR,适宜的Al/Ti(摩尔比)为0.9～1.2;合成的钛系IR的顺式-1,4-结构含量和硫化胶的物理机械性能与Zeon公司生产的钛系IR相当。展开更多
文摘The hydroxyl-terminated polybutadiene （HTPB） possessing high content of 1,4-units was synthesized by anionic polymerization of butadiene, using alkyllithium containing silicon-protected hydroxyl group as initiator and cyclohexane as solvent. The polymers were characterized by GPC, IR and 1H-NMR. The mechanical properties of cured films were also evaluated. The results show that the content of 1,4-units for HTPBs made by anionic polymerization reaches up to 90%. The molecular weight distribution is very narrow （〈 1.05）. The functionality of hydroxyl groups approaches 2. Compared with free radical HTPB, the elongation at break of anionic HTPB films increased by 70%, while the tensile strength remained nearly unchanged. This new HTPB can be very useful in solid propellant.
文摘以异戊二烯(Ip)为单体,Al(i-Bu)3(简称Al)/TiCi4(简称Ti)为催化剂(以100 g Ip计,Al、Ti的用量分别为2.27～3.77 mmol、4.08～6.81 mmol),芳香醚为活化剂,合成了异戊二烯橡胶(IR),考察合成钛系IR的影响因素,并将合成的钛系IR与日本Zeon公司生产的钛系IR的性能进行对比。结果表明,采用Al/Ti/芳香醚体系,可合成出顺式-1,4-结构质量分数大于97.00%的IR,适宜的Al/Ti(摩尔比)为0.9～1.2;合成的钛系IR的顺式-1,4-结构含量和硫化胶的物理机械性能与Zeon公司生产的钛系IR相当。
