P(E-CO-T)-N100预聚物的合成、表征及其在改性双基推进剂粘合剂体系中的应用

用本体聚合法合成了含—NCO端基的P(E-CO-T)-N100预聚物体系,并对其在交联改性双基推进剂粘合剂体系中的应用进行了研究。红外数据确定P(E-CO-T)-N100体系的预聚反应时间是180 min,X-ray结果显示P(E-CO-T)-N100预聚物没有结晶峰,是无定形的。预聚物与推进剂的主要组分硝化甘油(NG)、一缩二乙二醇二硝酸酯(DEGDN)和硝化纤维素(NC)的溶度参数差均小于4×10-3J0.5m-1.5,具有良好的相溶性。P(E-CO-T)-N100预聚物的加入使粘合剂体系的交联密度由1.03×10-5mol.cm-3提高到了2.17×10-5mol.cm-3,并且随着溶棉质量比{(NG+DEGDN)与〔NC+P(E-CO-T)-N100〕的质量比}的提高,粘合剂体系的交联密度(XLD)、凝胶分数(V2)、压缩模量Ep均急剧下降,而平均相对分子质量增大,说明网络结构逐渐松散,力学性能下降。常温力学性能数据显示,P(E-CO-T)-N100预聚物上的活性—NCO与NC上的—OH进行了交联,使粘合剂体系的延伸率达到191.70%,提高了73.48%。

Synthesis and Characterization of P(E-CO-T)-N100 and Its Application in Crosslinked Modified Double Base Propellant Binder

The prepolymer P(E-CO-T)-N100 system with end group —NCO was prepared through melt polymerization and its application in crosslinked modified double base propellant binder was investigated.FTIR results showed that the pre-curing time for P(E-CO-T)-N100 system is 180 min and X-ray results proved that the product is amorphous.The solubility parameter differences between the prepolymer and the main components(NG,DEGDN and NC) of double base propellant are less than 4×10-3 J0.5m-1.5,showing that P(E-CO-T)-N100 system has good compatibility with the later.Addition of P(E-CO-T)-N100 into propellant binder increased the crosslinking density(XLD) from 1.03×10-5 mol·cm-3to 2.17×10-5 mol·cm-3,and with the enhancement of the ratio of(NG+DEGDN) to [NC+P(E-CO-T)-N100],the XLD,gel content(V2) and compression modulus(Ep) all reduced rapidly,while the average molecular weight increased,indicating that the net structures of propellant binder are relaxed and the mechanical property falls.Mixing P(E-CO-T)-N100 into propellant binder system increased the extension ratio from 110.50% to 191.70%.