定应变下 NEPE推进剂化学老化性能研究

Study on Chemical Aging Properties of NEPE Propellant under Constant Strain

关键词:  NEPE推进剂  定应变  化学老化  化学结构  特征气体

Key words:  NEPE propellant  Constain strain  Chemical aging  Chemical structure  Characteristic gas

摘要:

为研究NEPE推进剂老化对其化学性能的影响，开展了10%压缩定应变下推进剂高温加速老化实验，测定了推进剂的傅里叶变换红外光谱、固体核磁共振谱、短周期与长周期特征气体释放量、扫描电镜图像、增塑剂与安定剂含量，研究了推进剂内部化学结构和释放的特征气体含量两种化学性能的变化规律。结果表明：随NEPE推进剂贮存老化时间的增长，与增塑剂相关的—CH ₂—O—NO ₂基团含量减小速率逐渐加快，与粘合剂及其固化体系相关的—CO—NH—基团含量先增加后逐渐减小、最终迅速减小，同时在老化初期和中期还存在少量与氧化作用相关的—CH(O)CH—特征基团产生。短周期监测时间内，NO ₂,NO,CO,HCl四种特征气体分别在老化2,3,3,7h时被检测到。长周期监测过程中，CO和NO气体初期增长缓慢，后期迅速增加；在老化初期和后期HCl增长较快，NO ₂气体则无明显的变化规律可寻。

Abstract:

A high temperature accelerated aging experiment of propellant under 10% compression constant strain was carried out, fourier transform infrared spectroscopy, solid state nuclear magnetic resonance spectrum, short and long period characteristic gas content, scanning electron microscope image and plasticizer and stabilizer contents were detected, and the internal chemical structures and characteristic gases contents of the propellant were studied to analyze the effects of NEPE propellant aging on its chemical properties. Results show that with the increase of storage aging time of NEPE propellant, the content reduction rate of —CH ₂—O—NO ₂ group, related to plasticizers, was getting faster, the —CO—NH— group, which is related to the binder and its curing system, increase first and then decrease gradually and finally decrease rapidly, and a lower amounts of —CH(O)CH— group related to oxidation is generated in the early and middle stages of aging. The short period detection results show NO ₂, NO, CO, and HCl were detected at 2, 3, 3, and 7 hours of aging. In the long period detection, the growths of CO and NO contents are initial slow and later increase rapidly, the HCl content grows faster in the early and late aging period, and there is no obvious law of NO ₂ content.