哑铃结构含氟多嵌段共聚物的合成和抗乳化性能机理

发布时间：2018-12-15 04:56

【摘要】：分水性能是衡量抗乳化剂品质的一项重要指标。据报道,具有超支化结构的破乳剂具有较强的亲水和渗透能力,这使得支链型破乳剂的破乳效果胜于直链型破乳剂;直链醚类破乳剂分离出的水色更清澈透明;另外,为了防止在破乳的过程中,抗乳化剂被分离出的水分带走,在保证破乳效果的同时,应使其具有较强的油溶性和化学稳定性。另外,含氟聚合物具有很高的化学惰性、热稳定性、优越的耐候性和疏水疏油的特性,我们合成了一系列哑铃结构的含氟多嵌段共聚物(Fluorinated Multi-block Copolymers with Dumbbell-shaped Structure,FMCDSs),并对其抗乳化性能及机理进行了研究。本文的第一部分主要是FMCDSs的合成及结构表征。通过阴离子开环聚合法合成了以聚乙二醇(PEG)为线性部分,聚缩水甘油醚(PG)为超支化部分的具有哑铃结构的超支化-线性-超支化聚醚(PG-b-PEG-b-PG)。以甲基丙烯酸三氟乙酯为氟化试剂,通过原子转移自由基聚合(Atom transfer radical polymerization,ATRP)技术,对PG-b-PEG-b-PG进行氟化改性,通过调节单体与引发剂的比例,得到了不同氟化程度的FMCDS-1、FMCDS-2、FMCDS-3。通过GPC、1HNMR、13CNMR、19FNMR等对其进行了结构表征。本文的第二部分研究了FMCDSs在150SN基础油-水体系的抗乳化性能及机理。研究发现:较低氟化程度的FMCDS-1在质量浓度为100 mg·L-1时在50秒内实现150SN基础油与水基本分离,FMCDS-2、FMCDS-3对应的最佳抗乳化性能的浓度分别为:200 mg·L-1、300 mg·L-1,对应的时间是分别是:53 s、101 s;界面张力不是影响其抗乳化性能的主要因素;含有FMCDSs的150SN基础油-水体系为弹性体系;扩张弹性模量的变化与分水时间的变化趋势基本一致,分水时间越短,抗乳化效果越好,扩张弹性模量越低;FMCDSs在油-水界面膜附近吸附聚集,降低了界面膜强度,使其难以形成稳定的乳液,最终导致界面膜局部结构损坏而实现破乳。
[Abstract]:Water partition is an important index to evaluate the quality of anti-emulsifier. It is reported that the demulsifier with hyperbranched structure has strong hydrophilic and permeable ability, which makes the demulsifying effect of branched-chain demulsifier better than that of straight-chain demulsifier, and the water color of straight chain ether demulsifier is clearer and transparent. In addition, in order to prevent the anti-emulsifier from being taken away by the separated moisture in the process of demulsification, the anti-emulsifier should have strong oil solubility and chemical stability while ensuring the demulsifying effect. In addition, fluorinated polymers have high chemical inertia, thermal stability, excellent weathering resistance and hydrophobic properties. We have synthesized a series of dumbbell structure fluorinated multiblock copolymers (Fluorinated Multi-block Copolymers with Dumbbell-shaped Structure,FMCDSs). The anti-emulsification property and mechanism were also studied. The first part of this paper is mainly about the synthesis and structure characterization of FMCDSs. Polyether (PG-b-PEG-b-PG) with dumbbell structure was synthesized by anion ring-opening polymerization with polyethylene glycol (PEG) as linear part and polyglycidyl ether (PG) as hyperbranched part. PG-b-PEG-b-PG was modified by atom transfer radical polymerization (Atom transfer radical polymerization,ATRP) with trifluoroethyl methacrylate as fluorination reagent, and the ratio of monomer to initiator was adjusted. FMCDS-1,FMCDS-2,FMCDS-3. with different fluorination degree was obtained. Its structure was characterized by GPC,1HNMR,13CNMR,19FNMR et al. In the second part of this paper, the emulsification resistance and mechanism of FMCDSs in 150SN base oil-water system were studied. It was found that FMCDS-1 with lower fluorination degree could achieve the basic separation of 150SN base oil and water within 50 seconds when the mass concentration was 100 mg L-1, FMCDS-2,. The optimum concentration of anti-emulsification property of FMCDS-3 is 200 mg L-1300 mg L -1, and the corresponding time is 53 s ~ 101s; The interfacial tension is not the main factor to influence the emulsion resistance, the 150SN base oil-water system containing FMCDSs is an elastic system. The change of dilated elastic modulus is basically consistent with that of water diversion time. The shorter the water separation time is, the better the anti-emulsification effect is, and the lower the expansion elastic modulus is. The adsorption and aggregation of FMCDSs near the oil-water interfacial membrane reduces the strength of the interfacial film and makes it difficult to form a stable emulsion which eventually leads to the destruction of the local structure of the interfacial membrane and the demulsification.
【学位授予单位】：山西大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O631.11

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