耐热型硼系填料对芳氧基聚磷腈绝热层性能的影响

Influence of heat resistant boron-based filler on the property of PDPP insulation

通过热重分析仪、硫化仪、力学性能和氧-乙炔烧蚀测试等方法,研究了氮化硼(BN)、硼粉(B)以及碳化硼(B_(4)C)3种耐热型硼系填料对芳氧基聚磷腈(PDPP)绝热层性能的影响。结果表明:PDPP绝热层烧蚀炭层不膨胀,且烧蚀炭层与基体层之间不易脱粘,具有优异的界面粘接性能;耐热型硼系填料能够显著提高PDPP绝热层的高温残炭值及改善其耐烧蚀性能;其中PDPP/BC绝热层的综合性能最佳,其拉伸强度为5.6MPa,断裂伸长率为211%,邵氏硬度为54HA,线烧蚀率为0.072mm/s。扫描电子显微镜分析表明添加耐热型硼系填料的PDPP绝热层形成的炭化层更加紧密,孔隙更小。

The effects of boron nitride(BN),boron powder(B) and boron carbide(B_(4)C) on the properties of poly(aryloxyphosphazene)(PDPP) insulation were studied by means of TGA,vulcanization apparatus, mechanical properties, and oxy-acetylene ablation tests.The results shown that the charred layer of PDPP insulation exhibited unsignificant expansion.And the charred layer was not easy to peel off form the virgin materials, which shown excellent bonding performance between charred layer and virgin materials.The heat resistant boron-based filler can significantly increase the yield char, and improved the ablation resistance of PDPP insulation.The PDPP/BC insulation layer had the best comprehensive performance, with the tensile strength of 5.6 MPa, elongation at break of 211%,shore hardness of 54 HA and linear ablation rate of 0.072 mm/s.The SEM microstructure shown that the charred layer of PDPP insulation with boron-based fillers was more compact and the pores were smaller.