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高分子量溴化环氧树脂阻燃剂制备研究
Study on the Preparation of High Molecular Weight Bromated Epoxy Resins for Flame Retardants
【作者】 贾修伟;
【导师】 刘治国;
【作者基本信息】 河南大学 , 高分子化学与物理, 2003, 硕士
【摘要】 高分子量溴化环氧树脂阻燃剂是新型高分子型溴系阻燃剂之一,除了具有优异的阻燃性能外,还具有耐迁移、耐析出和阻燃持久等特点,近几年在国外得到较快的发展。据文献报道,该产品在某些阻燃材料中将是十溴二苯醚的理想替代品之一,目前,仅有国外公司在销售该种产品,我国还没有实现真正的工业化生产,所以研制开发溴化环氧树脂阻燃剂具有重要意义,本文研究工作主要包括三方面的内容。研究以溴化钠/溴酸钠完全代替传统的溴素作为溴代试剂合成了四溴双酚A,避免了使用溴素和因溴素作为溴代试剂时产生的溴化氢对设备、操作人员以及环境的危害。详细研究了有机溶剂/水的比例、反应温度、反应时间、相转移催化剂、原料配比等因素对产品质量和收率的影响。研究表明有机溶剂可以重复使用且对产品质量和收率没有任何影响,首次在国内实现了四溴双酚A基本无污染工艺的合成。所得产品的熔点为180-182.1℃,溴含量为58.0%以上,元素分析、红外光谱等表征了产品的结构。研究以四溴双酚A和环氧氯丙烷为原料在二氧六环和水混合溶剂中一步法合成了高分子量溴化环氧树脂阻燃剂。详细研究了溶剂/水的配比、碱金属碱、相转移催化剂、反应温度、反应时间等因素对产品分子量和产率的影响。研究表明在溴化四甲基铵、溴化四乙基铵、聚乙二醇(分子量为6,000)和聚乙二醇(分子量为400)相转移催化体系中,氢氧化锂最好,氢氧化钾次之,氢氧化钠最次。研究还表明在碱金属氢氧化物环境中,溴化四乙铵和聚乙二醇(分子量为6,000)复合相转移催化剂比上面提到的任何单一相转移催化剂都好。在优化条件下改变原料配比和反应时间分别制备了分子量约为2.5×104、4.5×104和6.1×104的溴化环氧树脂阻燃剂,红外光谱证明了所得产品环氧端基的存在,元素分析证明产品的溴含量达52.0%上,热分析表明它们的热分解温度都在310℃以上。<WP=5>研究分子量分别约为2.5×104、4.5×104和6.1×104的阻燃剂产品对ABS的阻燃以及对ABS物理机械性能的影响。研究表明,随着产品分子量的增加,对ABS的综合物理机械性能影响越来越小,分子量为6.1×104的阻燃剂除了对ABS的悬臂梁缺口冲击强度影响较大外(这是目前所有溴系阻燃剂的一大缺陷,但这一缺陷可以通过其它技术进行弥补),ABS的其余物理机械性能几乎不受影响。阻燃性能测试表明,高分子量溴化环氧树脂阻燃剂阻燃ABS的氧指数大小恰与其对ABS的机械性能的影响相反,即分子量增大,氧指数降低,但还都在难燃范围之内,且水平和垂直燃烧实验都是离火即熄,都能达到UL94 V-0级。与十溴二苯醚对比试验研究表明,添加高分子量溴化环氧树脂阻燃剂的ABS材料溴含量为7.9%时与添加十溴二苯醚阻燃剂的ABS材料溴含量为10.1%的阻燃性能相当。
【Abstract】 High molecular weight bromated epoxy resins is a sort of the novel bromine-containing flame retardants which has excellent flame retardant efficiency and can not easily move from polymer materials. It has been researched and developed abroad recently. Some flame retardant polymer materials added the high molecular weight bromated epoxy resins as flame-retardant additive have been studied that such flame retardant agent has a combination of good fire retardant efficiency, UV stability, excellent mechanical properties, thermal stability and nonblooming ,which is the ideal substitute of decabromodiphenyl oxide. The real domestic industrialization for them has not been realized. Currently, there is only Dead Sea Bromine Group in Israel selling its products of these kinds of flame-retardants in our country. Therefore, the research and development of them is very important.The present work is dedicated to the research and development of new methods, which prepared tetrabromobisphenol A and high molecular weight bromated epoxy resins. The applied research of the high molecular weight bromated epoxy resins as flame retardant was studied at the same time.One subject of the present work relates to a green chemistry synthesis of tetrabromobisphenol A wherein the combination of sodium bromide and sodium bromated as brominating agent which completely replaces conventional liquid bromine. This new methods can shun corrosiveness of liquid bromine or gas hydrogen bromide released during bromating reaction to the equipments and eliminate harmfulness to the operating worker and environment.Detailed research is concerned with the conditions such as solvents, reaction time, reaction temperature, phase transfer catalyst and the ratio of raw materials having influence to the product’s quality and yield. It is also concerned with the organic solvent being recycled and having no influence to the quality and yield of the production. The melting point ranged from 180.0 to 182.1℃, and bromine-content of production is over 58.0% are same as to the production prepared by literature.<WP=7>One-step synthesis of the high molecular weight bromated epoxy resins for flame retardants is studied with tetrabromobisphenol A and epichlorohydrin as raw materials in mixed solvent comprising 1,4-dioxan and water.The findings of present work show that organic/water ratio,alkali metal alkali, phase transfer catalyst, reaction time, reaction temperature, all of them have influence to the molecular weight and yield of the production. In the presence of the phase transfer catalysts such as tetramethylammonium bromide, tetraethylammonium bromide or polyethylene glycol(MW 400 and 6,000),lithium hydroxide is the best alkali among lithium hydroxide ,sodium hydroxide and potassium hydroxide. In the presence of alkali metal hydroxide,the phase transfer catalyzed composition comprising of tetramethylammonium bromide and polyethylene glycol(MW 6,000) is more effective than any other phase transfer catalyzed systems made up of only one phase transfer catalyst such as tetrametylammonium bromide, tetraethylammonium bromide and polyethylene glycol(MW 400 and 6,000).Under the optimized conditions,three sort of products(MW 25×104,4.5×104 and 6.1×104) were prepared through varied conditions of the raw materials ratio and the reaction time. Bromine content of them is all over above 52.0%. All of their thermal decomposition temperature is over 310℃. The structures of finished products which have epoxy group at both end of their molecular chain proved by the infrared spectrum.Flame retardant properties and mechanical properties of ABS which was incorporated into different molecular weight bromated epoxy resins flame retardant agent were evaluated. Our studies investigated the comprehensive mechanical properties of ABS added bromated epoxy resin with different molecular weight are almost as good as that ABS added decabromodiphenyl oxide .But most preferable is 61 thousand among the different molecular weight products. The bromated epoxy resin w
- 【网络出版投稿人】 河南大学 【网络出版年期】2004年 01期
- 【分类号】TQ314.248
- 【被引频次】9
- 【下载频次】625