AlB_(2)@PVDF壳核结构制备及其在点火药中的应用

Preparation of AlB2@PVDF Core-Shell Structure and Its Application in Ignition Powder

为改善含硼(B)含能体系的能量释放,采用NaOH水溶液对原料AlB_(2)进行刻蚀,并采用PVDF对刻蚀AlB_(2)进行包覆,得到了AlB_(2)@PVDF壳核结构材料,并对其形貌和热行为进行了表征和测试;以KNO_(3)为氧化剂,分别以单质B、原料AlB_(2)、AlB_(2)@PVDF为可燃剂,制备了3种配方的点火药,并对其燃烧性能进行了对比研究。结果表明:刻蚀后AlB2的XRD谱图出现B基特征衍射峰;AlB_(2)@PVDF材料中PVDF以丝状和团状形态附着和悬挂在刻蚀AlB2的表面和沟壑内部;AlB_(2)@PVDF的实测燃烧热值为25.5 kJ·g^(-1),相比单质B提高了56.4%;与基于单质B的点火药相比,基于AlB_(2)@PVDF的点火药的燃烧火焰更稳定且燃烧更剧烈,其燃烧时间缩短了28.1%,平均燃烧温度提升了31.2%,最高燃烧温度提高了172.49℃。

In order to improve the energy release of boron(B)containing energetic systems,raw AlB_(2) material was etched using NaOH aqueous solution,and the etched AlB_(2) was coated by PVDF to obtain AlB_(2)@PVDF core-shell structured material.The morphology and thermal behavior of the AlB_(2)@PVDF material were characterized and tested.Using KNO_(3) as the oxidizer,three formulations of ignition powder were prepared with elemental B,raw AlB_(2),and AlB_(2)@PVDF as combustibles,respectively,and their combustion performances were comparatively studied.The results show that the XRD spectrum of AlB_(2) after etching exhibites B-based characteristic diffraction peaks;In the AlB_(2)@PVDF material,PVDF adheres and hungs in filamentous and clustered forms on the etched AlB_(2) surface and inside the grooves;The measured combustion calorific value of AlB_(2)@PVDF is 25.5 kJ·g^(-1),which is a 56.4%higher than that of elemental B;Compared with the ignition powder based on elemental B,the combustion flame of the ignition powder based on AlB_(2)@PVDF is more stable and intense,with a combustion time reduced by 28.1%,an average combustion temperature increased by 31.2%,and a maximum combustion temperature increased by 172.49℃.