School of Environment and Safety Engineering, North University of China, Taiyuan 030051, China.
Luzhou North Chemical Industries Co., Ltd., Luzhou 646000, Sichuan, China.
Molecules. 2020 Apr 23;25(8):1988. doi: 10.3390/molecules25081988.
Energetic binders are a research hot-spot, and much emphasis has been placed on their mechanical properties. In this study, propargyl-terminated ethylene oxide-tetrahydrofuran copolymer (PTPET) was synthesized. Then, PTPET and low-molecular-weight ester-terminated glycidyl azide polymer (GAP) were reacted by the click reaction without using catalysts to obtain a polyether polytriazole elastomer. Through tensile tests, where R = 0.5, the tensile strength reached 0.332 MPa, with an elongation at break of 897.1%. Swelling tests were used to measure the cross-linked network and showed that the cross-linked network regularity was reduced as R increased. The same conclusions were confirmed by dynamic mechanical analysis (DMA). In DMA curves, Tg was around -70 to -65 °C, and a small amount of crystallization appeared at between -50 and -30 °C, because locally ordered structures were also present in random copolymers, thereby forming localized crystals. Their thermal performance was tested by Differential Scanning Calorimeter (DSC) and Thermal Gravimetric Analyzer (TG), and the main mass loss occurred at around 350 to 450 °C, which meant that they were stable. In conclusion, the polyether polytriazole elastomer can be used as a binder in a composite propellant.
含能黏合剂是研究热点，其力学性能备受关注。本研究合成了末端炔基环氧乙烷-四氢呋喃共聚物（PTPET），然后通过点击反应在无需使用催化剂的情况下使 PTPET 与低分子量酯基端基叠氮化物聚合物（GAP）反应，得到聚醚型聚三唑弹性体。通过拉伸试验，当 R = 0.5 时，拉伸强度达到 0.332 MPa，断裂伸长率为 897.1%。溶胀试验用于测量交联网络，结果表明随着 R 的增加，交联网络的规则性降低。动态力学分析（DMA）也证实了相同的结论。在 DMA 曲线上，Tg 在-70 至-65°C 之间，在-50 至-30°C 之间出现少量结晶，因为无规共聚物中也存在局部有序结构，从而形成局部晶体。通过差示扫描量热仪（DSC）和热重分析仪（TG）测试其热性能，主要质量损失发生在 350 至 450°C 左右，表明其稳定。总之，聚醚型聚三唑弹性体可用作复合推进剂中的黏合剂。
