【作者】 郭建国；

【导师】 江建明；

【作者基本信息】 东华大学 ， 材料科学与工程， 2011， 博士

【摘要】 以醇为引发剂的环氧乙烷(EO)/环氧丙烷(PO)共聚醚,其亲水/亲油特性可通过调节分子中的EO/PO配比来实现；特别是经过末端羟基取代成为双烷基聚醚后,具有良好的耐热氧化性、化学稳定性、表面活性、生物降解性以及相对低的粘度和优良的润湿性能,故而成为一种重要的非离子型表面活性剂,具有广泛的用途。本论文主要对丙二醇引发的EO/PO无规聚醚这一较新的体系进行了研究。首先,探讨了聚合反应动力学,通过对聚合条件的优化分析实现了对产物结构的控制；采用核磁共振、红外光谱等方法对产物的结构进行了表征,并测定了耐热性、粘度、表面张力等性能指标,分析了聚醚结构与性能的关系：对产物水溶液的浊点进行了详细研究,考察了无规聚醚的浓度、分子结构以及无机电解质、酸、醇、表面活性剂等因素的影响；还合成了EO/PO嵌段聚醚并与无规聚醚的部分性能进行了比较。其次,采用Wiliamson法对无规聚醚进行了烷基化封端,探讨了影响封端率的各种因素；研究了双烷基聚醚的结构对其物化性能的影响以及双烷基聚醚水溶液的流变性能、浊点、稳定性和表面活性；并对一步法合成双烷基聚醚新工艺进行了探索。最后,尝试了双乙基聚醚在锦纶66高速纺油剂方面的应用,探讨了双乙基聚醚油剂复配体系的热氧稳定性及其对纤维可纺性的影响。以上研究得到的主要结论如下：1.聚合反应温度升高,反应速度加快,但温度过高会导致产物的不饱和度高、颜色深；催化剂浓度增加,反应速度加快；EO/PO配比增加产物的相对分子质量越接近设定值。经过优化分析后,采用连续滴加单体的方法以丙二醇引发合成无规聚醚,催化剂KOH用量为0.25%(对产物重),反应温度为115℃,反应压力小于0.4MPa,所得产物相对分子质量分布较窄且无色透明。2.无规聚醚的结构对其性能有较大影响。总体看来,随EO/PO配比以及相对分子质量的增加,无规聚醚的粘度、表面张力和乳化力增大,热失重率降低；但引发剂碳链长度增加时,粘度和表面张力下降。3.无规聚醚分子中EO含量越少、相对分子质量越大、浓度(一定范围内)越高,其水溶液的浊点越低；盐、碱及非水溶性醇类能降低而水溶性醇和酸类能提高聚醚的浊点：离子表面活性剂能显著提高聚醚的浊点,而非离子型表面活性剂的影响相对较小。4.嵌段聚醚的热失重塞低于无规聚醚,但二者组成相同时浊点差别不明显。5.采用KOH固体或水溶液催化体系对无规聚醚进行封端,丁基和乙基封端率均能达85%以上；封端后聚醚的抗热氧化性显著提高,随封端率的增大,双烷基聚醚的起始分解温度提高而分解速度加快；乙基封端后聚醚的乳化力无大的变化而丁基封端的略有降低；随封端率的提高,聚醚的浊点和粘度降低,且粘度受温度的影响越小。6.封端后的双烷基聚醚与羟基聚醚相比,水溶性受酸、碱和盐的影响程度变小,水溶液的稳定性提高；表面活性更佳、降低水溶液表面张力的能力更强；水溶液除了相应的粘度下降外粘浓、粘温等规律不变。7.一步法封端新工艺能使丁基封端率达到31%,乙基封端率达到33%。8.双乙基聚醚复配得到的纺丝油剂的热氧稳定性要优于相应的羟基聚醚油剂,且在同样的升温速率下能够更快的达到完全分解。9.对比于羟基聚醚,采用乙基封端率为33%的聚醚复配油剂时锦纶66可纺性更佳,但采用这两种油剂原丝质量均能达到标准要求。更多还原

【Abstract】 Copolymerization between ethylene oxide (EO) and propylene oxide (PO) could be initiated by alcohols and the hydrophilic-lipophilic property of resulted copolyethers could be tailored by adjusting EO/PO ratio. After being alkyl-end-capped, EO/PO copolyether would show fine properties of thermostability, chemical resistance, fast wetting, foam-reducing and biodegradation, and then could act as an important nonionic surfactant in a wide application field.In this paper, the attention has been focused mainly on a new system of the propylene glycol initiated EO/PO random copolyethers. Firstly, the polymerization kinetics has been studied and the controlling on copolyether molecular structures was successfully achieved based on the optimization design on the polymerization parameters. The copolyethers have been characterized by means of NMR, FT-IR, etc., and their thermostability, viscosity and surface tension were also tested. Moreover, the influence of molecular structure, concentration, adding of inorganic electrolytes, acids, alcohols and different surfactants on the cloud point (CP) of aqueous solution of random copolyethers has been discussed in detail. Furthermore, some block EO/PO copolyethers were synthesized for the purpose of comparison with the random counterparts. Secondly, the random copolyethers were alkyl-end-capped via Wiliamson method and the factors determining end-capping degree were discussed. The influence of end-capping on the properties of copolyethers as well as the rheology. CP, stability and wetting ability of end-capped copolyether solutions were also studied. Especially, a new one-step polymerization technology of alkyl-end-capped copolyethers has been developed. Finally, an attempt at the application of confected end-capped copolyethers on spinning finish was made, and the thermostability of alkyl- end-capped copolyethers along with their effects on the high speed spinnability of PA66 was discussed. The main conclusions were listed as follows.1. The polymerization rate could be accelerated by increasing the reaction temperature and the catalyst concentration, however, excessively high temperature would also result in the higher unsaturation level and darker color of the copolyethers. Moreover, with the increasing load ratio of EO/PO, the molecular weight (MW) of resulted copolyethers would reach closer to the desired one. After the optimization analysis of reaction parameters, random copolyether could be synthesized from propylene glycol initiated EO/PO mixture under the conditions of catalyst KOH content being 0.25%, temperature being 115℃, and pressure below 0.4MPa, resulting a product with an narrow MW distribution and a colorless appearance.2. The molecular structures of copolyethers impacted heavily on their properties. Generally, the viscosity, surface tension and emulsion ability increased while the thermostability decreased with the increasing EO/PO ratio and MW. However, a long alkyl chain of the initiator would reduce the viscosity and surface tension.3. A low EO content, high MW and high concentration (to some extent) of the copolyethers would result in a low CP. Furthermore, electrolytes, bases and insoluble alcohols would reduce but acids, water soluble alcohols and surfactants would improve the CP.4. With a similar composition, the thermostability of block copolyethers was higher than that of random ones however CP was almost the same.5. The random copolyethers mentioned above have also been alkyl-end-capped with KOH (in both bulk and aqueous solution state) as a catalyst, under which the end-capping degree for both ethyl and butyl could reach over 85%. After end-capping, the thermostability of copolyethers was improved evidently, which was demonstrated by the increased onset decomposition temperature with the increasing end-capping degree. The emulsion ability of ethyl-end-capped copolyether changed little however butyl-end-capped one decreased slightly. With the increscent end-capping degree, the CP and the viscosity of copolyethers would decrease and the temperature effect on viscosity became weaker.6. After the alkyl groups substituting the terminal hydroxyls, the influence of acids, bases and salts on water-solubility of copolyethers decreased and the stability of water solution increased, the wetting ability was also improved. End-capping degree has little effect on the concentration and temperature dependence of rheology except for the slight decreasing of viscosity, especially, the temperature effect on viscosity became weak under a high end-capping degree.7. An end-capping degree of 33% for ethyl group and 31% for butyl group could be achieved from the new one-step polymerization technique for preparing alkyl-end-capped copolyethers.8. Confected spinning finish obtained from alkyl-end-capped copolyethers showed a better thermostability and could reach to entire decomposition more quickly under a same heating rate.9. Confected spinning finish obtained from 33% ethyl-end-capped copolyethers could promise better high speed spinnability to PA66 than hydroxyl-ended ones, however, the as-spun fibers obtained from each kind of finish could satisfy the standard quality demands.更多还原