高燃速HTPB/IPDI推进剂低温力学性能研究(Ⅰ)细AP及工艺助剂PA的影响

Study on the Low Temperature Mechanical Properties of High-Burning Rate HTPB/IPDI Propellant (Ⅰ) Effects of Fine AP and Processing Aid PA

研究了细粒度 AP及工艺助剂 PA含量对丁羟高燃速推进剂低温 (-4 0℃ )力学性能的影响 ,结果显示 :大量细粒度AP加入高燃速配方中 ,一方面加剧了单向拉伸过程中填料 (主要是细 AP)颗粒附近的应力集中 ;另一方面降低了填料 /粘合剂间的粘结强度 ,是造成低温力学性能偏低的主要原因。由于工艺助剂 PA极性及刚性 ,使得它易于富集于填料表面 ,低温下降低了界面层的柔性 ,物理作用也极大地束缚了填料附近粘合剂网络的分子运动 ,因此 ,它在改善工艺性能的同时 ,对推进剂低温力学性能有不利影响。

The effects of the content of fine APand processing aid PA on the low temperature (-40℃) mechanical properties (LTMP) of high burning-rate HTPB/IPDI propellant are studied. On the basis of experimental results,it is concluded that adding the massive fine AP is the main reason of LTMP of the propellant,resulting in an increase of stress concentration around the filler (fine AP) during uniaxile tensile test on one hand and a decrease of the bonding strength between filler/binder on the other hand.Because of the high polarity and rigidity of PA,PA tends to gather together the surface of fine AP.This decreases the flexibility of interface layer,moreover the physical fuction tends to bind up the molecular movements of matrix around the filler.Therefore PA can improve processing properties,but it brings to a disadvantage effects on the LTMP of propellant at -40℃。