【作者】 陈聪；

【导师】 陈卫航； 王宏力；

【作者基本信息】 郑州大学 ， 化学工程， 2012， 硕士

【摘要】 酚醛树脂性能优良,是一种与各种各样的有机和无机填料都能相容的多功能物质。由于酚醛树脂结构上的酚羟基和亚甲基很容易被氧化,使得酚醛树脂产品的机械强度和耐热性降低,所以纯的酚醛树脂已经不能满足现代工业的要求。将酚醛树脂和其他一些具有优良性能的聚合物共混,利用不同聚合物之间性能的互补可以有效改善酚醛树脂的物理、化学和机械性能。本研究通过改性三聚氰胺甲醛树脂与酚醛树脂的共混,提高其贮存稳定性、黏性和韧性,从而提高酚醛树脂的机械性能。实验首先对三聚氰胺甲醛树脂的合成工艺进行优化。考察反应物料的配比、羟甲基化反应温度、羟甲基化反应时间以及醚化反应温度四个可变因素,设计正交实验,并对反应体系pH值进行单因素考察。最终优化得到的工艺条件为：反应物物质的量的比为1：5：5：羟甲基化反应pH值为8.0～9.0,反应温度为85℃,反应时间为30min:醚化反应pH值为5.0-5.5,反应温度为50℃。在此基础上采用聚乙二醇对其改性,以动力粘度作为改性树脂的质量指标,考察聚乙二醇的最佳加入条件以及加入量。由单因素考察实验可知,聚乙二醇改性树脂实验的最优工艺条件为：在合成三聚氰胺甲醛树脂的优化工艺条件下,羟甲基化反应进行10min时,加入聚乙二醇2.3%,尿素1.4%(两者均按占三聚氰胺和甲醛总质量的百分比计)。最后将改性三聚氰胺甲醛树脂替代15%的酚醛树脂,进行酚醛树脂砂轮应用实验。用改性和未改性的酚醛树脂分别制作砂轮,对比两组树脂砂轮产品的回转强度、静平衡试验以及磨削比。实验结果显示,回转强度提高了4.91%,标准等级由合格变为优等；允许的最大静不平衡数值由9变为6,等级也由良好变为优等；磨削比由7提高至8.5,等级从合格变为优等。更多还原

【Abstract】 Phenolic resin is a kind of multi-functional and good performance material. It can be compatible with many kinds of organic and inorganic packing. An important use is as binder., now, the low mechanical strength and heat resistance of pure phenolic resin can’t satisfy the requirements of modern industry, because the phenolic group and the methylene in the structure of phenolic resin is easily oxidized. So it needs to be modified to phenolic resin. Blending the the modification melamine formaldehyde resin and the phenolic resin is a good way, we can mix other excellent performance polymer with phenolic resin to improve the physical, chemical and mechanical properties of phenolic resin.Due to the structural, melamine formaldehyde resin is poor storage stability, high hardness, high brittleness and almost no toughness. So, In this experiment, we can optimize and modify the process condition of melamine formaldehyde resin, on the basis of the optimization and modification, we can improve the mechanical properties of the phenolic resin.First, we optimize the synthetic process of melamine formaldehyde resin, In this study, we research four variables:response of the material ratio, reaction temperature and reaction time of hydroxymethylation, temperature of etherification reaction, then we use the orthogonal table to obtain the best Process condition: Reactant molar ratio of1:5:5,,hydroxymethylation pH of8.0-9.0, temperature of85℃, hydroxymethyl reaction time of30min, etherification pH of5.0-5.5, temperature of50℃.On the basis of the optimization, we use the polyethylene glycol (PEG) as modifier. By dynamic viscosity as quality indexes, we research the best join condition and addition amount of PEG through single factor experiment, the optimum process conditions is joining PEG2.3%. urea1.4%during Hydroxymethylation reaction.Finally, we make the modified melamine formaldehyde resin replace15%phenolic resin, and then we do grinding wheel application experiment with modified phenolic resin and pure phenolic resin respectively. We compare the rotary strength, static balance tests and grinding ratio of them. The results show that, rotary strength increased by4.91%, the standard level by qualified into superior; Maximum static unbalance values from9to6, by the level become superior; Grinding ratio increase from7to8.5. the standard increase two level.更多还原