高氯酸铵的微纳结构化及其防吸湿性能的研究

发布时间：2018-04-28 20:09

本文选题：疏水 + 高氯酸铵　；参考：《西南科技大学》2017年硕士论文

【摘要】：高氯酸铵(AP)因其较高有效含氧量而作为氧化剂被广泛应用于军事及航天领域,但在实际应用过程中AP易吸湿而对其使用性能造成影响,因此为提高AP的使用性能需对其进行疏水改性处理,以防止AP吸湿,关于AP的防吸湿研究报道很多,但尚未见从微纳结构和表面处理相结合的方式改善AP防吸湿性能的报道。本文通过AP的微纳结构化,结合表面处理技术,制备了AP/SiO_2复合材料以及AP/CBC纳米结构材料。主要研究内容如下:(1)AP/SiO_2复合材料的制备与表征。通过溶胶凝胶法制备了AP/SiO_2复合材料,并采用聚甲基氢基硅氧烷(含氢硅油PMHS),十二氟庚基丙基三甲氧基硅烷(氟硅烷FAS)和甲基三乙氧基硅烷(MTES)为表面改性剂对AP/SiO_2复合材料进行表面改性处理,以提高复合材料的防吸湿性能。采用SEM-EDS、XRD、FT-IR、接触角测试、吸湿率测试对AP及其复合材料的形貌、成分、分子结构以及防吸湿性能进行表征。研究结果表明:AP、SiO_2以及改性剂是有机复合在一起的,AP均匀的填充在SiO_2的孔洞中并且表面被一层表面改性剂所包覆。纯AP的接触角为0°,而经过PMHS、FAS、MTES改性后的AP/SiO_2复合材料的接触角分别为(64±2)°(50±2)°(42±2)°,相比于纯AP有很大的提高说明其疏水性较AP有很大的提升。吸湿性测试表明48h后AP的吸湿率为1.13%,而经过改性处理的AP/SiO_2复合材料吸湿性均小于纯的AP,并且经过PMHS改性后的AP/SiO_2复合材料的吸湿性最低仅为0.24%。(2)AP/CBC纳米结构材料的制备与表征。以高氯酸铵(AP)和碳化细菌纤维素(CBC)为原料,并以PMHS、FAS和MTES为表面改性剂,采用溶液分散-冷冻干燥法制备疏水AP/CBC纳米结构材料。通过扫描电子显微镜、红外光谱仪、X射线衍射仪、恒温恒湿箱、接触角测试仪等分别表征了AP/CBC纳米结构材料的微观形貌、分子结构、吸湿性能等。结果表明,AP/CBC纳米结构材料的形貌变化较大,纳米结构材料是以CBC为网络骨架结构,AP均匀的分散在CBC骨架所形成的孔洞中。对AP/CBC纳米结构材料进行表面改性后,材料表面被包覆并且表面变得光滑。由于改性剂表面含有大量的疏水基团,因此能有效阻止AP的吸潮,并且由CBC构筑的这种结构能够有效防止AP的团聚以及包覆层的脱落。接触角测试表明纯AP的接触角为0°,而经过PMHS、FAS、MTES改性后的AP/CBC纳米结构材料的接触角分别为(109±2)°(56±2)°(55±2)°,相比于纯AP有较大的提高。吸湿性测试表明20天后AP的吸湿率为1.89%,而经过改性处理的AP/CBC纳米结构材料吸湿性均小于纯的AP,其中经过PMHS改性后的AP/CBC纳米结构材料的吸湿性最低仅为0.31%。本研究通过选用合适的结构材料构筑具有特殊结构的AP复合材料,再选用疏水改性剂对AP复合材料进行疏水表面的改性,既提高了高氯酸铵的防吸湿性能也为水溶性无机盐类物质由亲水性向疏水性转变提供了新的思路。
[Abstract]:Ammonium perchlorate (APO) is widely used as an oxidant in military and aerospace fields because of its high effective oxygen content. However, AP is easy to absorb moisture in practical application, which affects its performance. Therefore, in order to improve the performance of AP, hydrophobic modification is needed to prevent AP from absorbing moisture. There are a lot of researches on AP, but there is no report on how to improve the performance of AP by combining micro-nano structure with surface treatment. In this paper, AP/SiO_2 composites and AP/CBC nanostructured materials were prepared by micro-nano structure of AP and surface treatment technology. The main research contents are as follows: preparation and characterization of APS / SiO2 composites. AP/SiO_2 composites were prepared by sol-gel method. Polymethylhydrosiloxane (PMHSN), dodecafluoroheptyl trimethoxy silane (FASS) and methyl triethoxysilane (MTESs) were used as surface modifiers to modify the surface of AP/SiO_2 composites. In order to improve the hygroscopicity of composite materials. The morphology, composition, molecular structure and hygroscopicity of AP and its composites were characterized by SEM-EDSX XRDX FT-IR, contact angle test and moisture absorption test. The results show that the SiO_2 pore is uniformly filled with the organic composite of the two modifiers, and the surface is coated with a layer of surface modifiers. The contact angle of pure AP is 0 掳, and the contact angle of AP/SiO_2 composite modified by PMHS-FAS-MTES is 64 卤2 掳50 卤2 掳or 42 卤2 掳respectively, which indicates that the hydrophobicity of pure AP is much higher than that of pure AP. The hygroscopicity test showed that the moisture absorption rate of AP was 1.13 after 48 h, while the moisture absorption of modified AP/SiO_2 composites was lower than that of pure APs, and the lowest hygroscopicity of AP/SiO_2 composites modified by PMHS was only the preparation and characterization of 0.24%.(2)AP/CBC nanostructured materials. The hydrophobic AP/CBC nanostructured materials were prepared by solution dispersion-freeze-drying method using ammonium perchlorate (APP) and carbonated bacterial cellulose (CBC) as raw materials and PMHSS-FASA and MTES as surface modifiers. The microstructure, molecular structure and hygroscopicity of AP/CBC nanostructures were characterized by scanning electron microscope, infrared spectrometer, X-ray diffractometer, constant temperature and humidity box, contact angle tester, etc. The results show that the morphology of CBC / CBC nanostructure material varies greatly. The nano-structure material is composed of CBC as the network skeleton structure and AP is uniformly dispersed in the pores formed by the CBC skeleton. After surface modification of AP/CBC nanostructured material, the surface of the material is coated and the surface becomes smooth. Because there are a lot of hydrophobic groups on the surface of the modifier, the moisture absorption of AP can be effectively prevented, and the structure constructed by CBC can effectively prevent AP from agglomeration and the coating layer from falling off. The contact angle test showed that the contact angle of pure AP was 0 掳, while that of the modified AP/CBC nanostructure material was 109 卤2 掳/ 56 卤2 掳/ 55 卤2 掳, which was higher than that of pure AP. The hygroscopicity test showed that the moisture absorption rate of AP was 1.89 after 20 days, but the moisture absorption of modified AP/CBC nanostructured materials was lower than that of pure APs. The lowest moisture absorption of AP/CBC nanostructured materials modified with PMHS was 0.31. In this study, AP composites with special structure were constructed by selecting suitable structural materials, and hydrophobic modifiers were used to modify the hydrophobic surface of AP composites. It not only improves the hygroscopicity of ammonium perchlorate, but also provides a new idea for the transformation of water-soluble inorganic salts from hydrophilicity to hydrophobicity.
【学位授予单位】：西南科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ113.72;V512

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