【作者】 薛建荣；

【导师】 高俊； 钟宏；

【作者基本信息】 内蒙古工业大学 ， 化学工艺， 2007， 硕士

【摘要】 本文以硫酸镁和氢氧化镁为原料,进行了水热法制备碱式硫酸镁晶须和碱式硫酸镁片状粉体的工艺研究。采用化学分析、扫描电子显微镜（SEM）、X-射线衍射（XRD）和红外光谱分析（FT-IR）等测试手段对产物进行了表征,并对碱式硫酸镁晶须填充高密度聚乙烯树脂后的性能进行了研究。研究结果表明,不同的反应条件对碱式硫酸镁晶须的合成有不同的影响。通过分析比较,得出合成晶须产品的适宜水热条件为:硫酸镁料浆浓度1.28 mol·L^-1、硫酸镁和氢氧化镁的摩尔比1～4、搅拌强度450r/min、反应温度200℃,反应时间6h。此时合成的碱式硫酸镁晶须平均长度为20～45μm,长径比为31以上,表面光滑,纤细均匀且无弯曲,纯度较高。在合成晶须的过程中,除考虑水热合成的各种影响因素外,考察了有机羧酸类（酒石酸、柠檬酸）和磷酸盐类（磷酸钠、磷酸二氢钠与次磷酸二氢钠）等晶体助长剂对合成产物的影响。合成产物外观与晶须有很大的区别,呈现白色的细粉末状,在扫描电子显微镜下观察呈现有规则的片状、扇形和层叠状结构。显示平均长度为2μm,厚度为0.052μm,化学式:MgSO₄·5Mg（OH）₂·2H₂O。因为没有见到有关的报道,试验者把它称为碱式硫酸镁片状粉体。对应的最佳反应条件为:硫酸镁和氢氧化镁的摩尔比0.65∶0.25,硫酸镁料浆浓度1.00 mol·L^-1,NaH₂PO₄和Na₃PO₄是作用效果明显的晶体助长剂,反应温度200℃,搅拌强度200 r/min,反应时间5 h,并且对其进行了相关表征。把自制的碱式硫酸镁晶须用偶联剂进行表面活性处理后,填充到高密度聚乙烯树脂塑料中,与目前工程塑料中普遍使用的氢氧化镁填料相比较,碱式硫酸镁晶须对改善复合材料的机械性能和阻燃性能均超过氢氧化镁填料。更多还原

【Abstract】 Hydrothermal Method synthesizing Magnesium Hydroxide Sulfate Whiskers and flake MgSO₄·5Mg（OH）₂·2H₂O powders using MgSO₄ and Mg（OH）₂ were described. The as-prepared samples were analyzed by chemical analysis and characterized by XRD, SEM and FT-IR spectra and so on. The mechanical and flame resistance properties of the whiskers added into high-density polyethylene（HDPE） were also studied in this paper.Based on the morphology and crystal structure of Magnesium Hydroxide Sulfate Whiskers, the different experiment conditions of hydrothermal synthesizing exercise different influence on synthesizing process. And the best technological conditions for preparing the Magnesium Hydroxide Sulfate Whiskers were put forward as : the concentration of MgSO₄ is 1.28 mol·L^-1; the mol rate of MgSO₄ to Mg（OH）2 is 1～4; the reaction temperature is 200℃; the stir intensity is 450r/ min,and the reaction time is 6h.The nice morphology MgSO4·5Mg（OH）₂·2H₂O whiskers of about 20～45μm/ long and about 31 rate of long to diameter is obtained .Besides considering the hydrothermal conditions,adding additives（citric acid,phosphate） into the autoclave were investigated.The result showed that flake white powers were synthesized.According to processes of investigating whiskers,the flake powers were studied correlatively.The SEM shows that the morphology of the powder is flake,sector and samdwich,and long /2μm, thickness/0.052μm. Its molecular formulais MgSO₄·5Mg（OH）₂·2H₂O.The optimal reactive synthesizing conditions for synthesizing the flake powers were brought forward as :MgSO₄ :1.00mol·L^-1;MgSO₄ to Mg（OH）₂ :0.65:0.25;200℃; 200r/min;5h.The results of tensile and flame tests of compound material showed the HDPE containing as-prepared whiskers had better overall properties,excessing the properties of HDPE/ Mg（OH）₂.更多还原