RDX含量对改性双基推进剂动态力学性能的影响

利用动态热机械分析(DMA)研究了一组不同黑索今(RDX)含量的改性双基推进剂的低温动态力学性能。β松弛的峰温几乎不受固体填料加入的影响。认为RDX含量超过一定值时,在低温下将起到辅助增塑作用,β松弛tanδ峰值与"等效增塑剂"的含量有关。经拟合得到"等效增塑剂"的含量。从推进剂的动态模量主曲线获得了β松弛的粘弹系数Cg1,Cg2以及松弛过程(分子构象变化)的活化能Ea,以及"脆化参数"m,并用线性方程关联了"脆化参数"m与低温抗拉强度σm和延伸率εm。

Effect of RDX content on dynamic mechanical properties of modified double-base propellants

The dynamic mechanical properties of a series of modified double-base propellants with various amounts of RDX at low temperature were characterized by using dynamic mechanical analyzer.The peak temperature of the β-relaxation was not affected by adding solid filler.It is considered that when the RDX content exceeds some certain percent it would appear an effect as auxiliary plasticizer and the relation of the peak magnitudes for tan δ on the β-relaxation with the equivalent plasticizer was obtained.Thus through the regression relation the equivalent plasticizer concentration could be calculated.The viscoelastic coefficients Cg1,Cg2 and the activation energy Ea on the β-relaxation transition(the molecular configuration conversion) from the master curves of propellants,and the fragility parameters m were obtained.A linear equation was used to relate fragility parameter m with the tensile strength σm and the percentage elongation εm at low temperature.