PDA包覆铝粉及其在HTPB中的分散稳定性

Polydopamine Coated on Aluminum Powders and Its Disperse Stability in HTPB

通过原位多巴胺(DA)聚合法在铝粉表面包覆聚多巴胺(PDA),制备了Al@PDA复合颗粒;采用SEM表征不同DA质量浓度下Al@PDA的表面形貌。用XRD测试铝粉包覆前后的晶型;采用XPS分析Al@PDA的表面元素组成;通过沉降法研究了铝粉和Al@PDA在HTPB中的分散稳定性;通过制备固化胶并切片取样观察固体颗粒在HTPB中的分散情况。结果表明,当DA质量浓度为3.5g/L时对铝粉的包覆效果最好,在铝粉表面形成牢固的PDA薄膜;包覆前后Al的晶型没有改变;XPS在Al@PDA表面检测到的C-OH、C=O组分和π-π共轭结构证实了PDA包覆层的存在。沉降24h后Al-HTPB体系出现分层,而Al@PDA-HTPB体系仍然颜色均一,表明Al@PDA在HTPB中的分散稳定性明显优于原料铝粉。

Al@PDA composite particles were prepared via.coating aluminum powder surface by polydopamine(PDA)using the in-situ polymerization method of dopamine(DA).The surface morphology of Al@PDA at different concentrations of dopamine(DA)was characterized by SEM.The crystal type of Al powder before and after coating was tested by XRD.The surface element composition of Al@PDA was analyzed by XPS.The disperse stability of Al powder and Al@PDA in HTPB was investigated by sedimentation method.The dispersion of solid particles in HTPB was observed by preparing curing adhesive and sliced sheet sampling.The results show that when the mass concentration of DA is 3.5g/L,the coating effect to aluminum powder is the best,and a firm PDA thin film was formed on the surface of aluminum powders.The crystal type of Al powder before and after coating does not change.The presence of PDA coating layer is demostrated by the components of C-OH,C=O andπ-πconjugated structure on the surface of Al@PDA detected by XPS.After settling for 24 h,the stratification is observed in AlHTPB system,while the Al@PDA-HTPB system still has homogeneous color,showing that the disperse stability of Al@PDA in HTPB is obviously better than raw material aluminum powder.