本文選題：超支化聚酯 + 親水改性��； 參考：《長春工業(yè)大學》2015年碩士論文

【摘要】：滲透汽化是一種實驗過程簡單、高效節(jié)能的新型膜分離技術,尤其是用于有機物脫水領域。而有機物脫水對所用的膜材料的親水性要求較高,聚乙烯醇(PVA)是一種優(yōu)良的親水性膜材料。為了使其更加適用于滲透汽化脫水,提高其應用范圍和能力,目前的研究熱點集中在對PVA膜進行改性方面。超支化聚酯是一種有著高度支化結構聚合物,它不易結晶、分子間不易發(fā)生纏繞、末端含有大量活性基團,并且其合成方法相對簡單,使得其工業(yè)生產成本較低,因而引起了越來越多的關注。本文以2,2-雙羥甲基丙酸為AB2單體,季戊四醇為核,在對甲苯磺酸催化條件下,通過“準一步”聚合法,合成了含有端羥基的超支化聚酯(HBPE),利用順丁烯二酸酐對HBPE的末端進行接枝反應,成功完成了其端基的改性,最終合成了水溶性超支化聚合物(WHBP),通過核磁和紅外表征確定了HBPE已經成功完成端基的改性。然后以戊二醛為交聯(lián)劑,制備了一系列不同比例的新型WHBP/PVA交聯(lián)膜,通過傅里葉紅外光譜(FTIR),X射線衍射(XRD),掃描電鏡(SEM),機械強度,熱重分析(TG)和水接觸角等測量與表征,分析了和評價了該系列膜的物理化學特性。結果表明WHBP/PVA膜具有良好的熱力學穩(wěn)定性,較強的機械性能和高的親水性。研究了不同含量的WHBP/PVA膜在正丁醇和水中的吸附和擴散行為,結果表明WHBP/PVA膜對水有較強的選擇性吸附,并且隨著WHBP含量的增加,吸附選擇性增強,說明加入的WHBP增加了PVA膜的親水性能。實驗還考察了WHBP含量對WHBP/PVA膜滲透汽化性能的影響,將WHBP/PVA膜用于研究分離60℃10 wt.%水/正丁醇體系。具體考察了WHBP的含量對滲透通量、分離因子和滲透汽化分離指數(shù)的影響,結果發(fā)現(xiàn)隨著WHBP含量的增加,WHBP/PVA膜的通量是增加的,但伴隨著分離因子的下降,這是膜在滲透汽化性能評價方面不可避免的現(xiàn)象。而滲透汽化指數(shù)(PSI)呈現(xiàn)了先增加后降低的趨勢。M-3(10%)在60℃分離10%的水/正丁醇體系時擁有最高的PSI值2.31×105,表現(xiàn)出了最佳的滲透汽化性能。單從膜的內在屬性方面,考察了WHBP的含量對滲透性和滲透選擇性的影響,滲透性隨著WHBP含量的增加而增加,相反,滲透選擇性減少。含量為10%的WHBP/PVA膜(M-3)表現(xiàn)出較高的滲透性4.00×10-3 g m-1 h-1 kPa-1和良好的選擇性785。研究結果表明,WHBP含量為10%的WHBP/PVA膜(M-3)具有相當好的滲透汽化分離效果,可以選擇作為后續(xù)具體研究的對象。對于后續(xù)研究,主要考察了料液濃度和料液溫度對WHBP/PVA膜分離性能的影響,結果發(fā)現(xiàn)隨著料液濃度的增加,膜的PSI值始終都表現(xiàn)較高,說明本實驗制備的WHBP/PVA膜的滲透汽化性能優(yōu)越。溫度對WHBP/PVA膜的影響較大,高溫是有利于滲透汽化分離的。
[Abstract]:Pervaporation is a new membrane separation technology with simple experimental process and high efficiency and energy saving, especially in the field of organic dehydration. However, dehydration of organic compounds requires high hydrophilicity of membrane materials. PVA (polyvinyl alcohol) is an excellent hydrophilic membrane material. In order to make it more suitable for pervaporation dehydration and improve its application scope and ability, the current research focus is on the modification of PVA membrane. Hyperbranched polyester is a kind of polymer with highly branched structure. It is not easy to crystallize, is not easy to twine between molecules, has a large number of active groups at the end, and its synthesis method is relatively simple, which makes its industrial production cost low. As a result, more and more attention has been paid. In this paper, in the presence of 2-dimethylolpropionic acid as AB2 monomer, pentaerythritol as nucleus and p-toluenesulfonic acid as catalyst, the polymerization was carried out by "quasi-step" polymerization. The hydroxyl terminated hyperbranched polyester (HBPEE) was synthesized. Maleic anhydride was used to graft the end of HBPE, and the modification of its terminal group was successfully completed. Finally, the water-soluble hyperbranched polymer (WHBP) was synthesized, and the modification of the terminal group of HBPE was confirmed by NMR and IR characterization. A series of novel WHBP/PVA crosslinking films with different proportions were prepared with glutaraldehyde as crosslinking agent. The WHBP/PVA films were measured and characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), mechanical strength, thermogravimetric analysis (TG) and water contact angle. The physicochemical properties of the films were analyzed and evaluated. The results show that WHBP/PVA film has good thermodynamic stability, strong mechanical properties and high hydrophilicity. The adsorption and diffusion behavior of WHBP/PVA membrane with different contents in n-butanol and water were studied. The results showed that WHBP/PVA membrane had strong selectivity to water, and the adsorption selectivity increased with the increase of WHBP content. The results show that the addition of WHBP increases the hydrophilicity of PVA membrane. The effect of WHBP content on the pervaporation performance of WHBP/PVA membrane was also investigated. The WHBP/PVA membrane was used to study the separation of 10 wt.% water / n-butanol system at 60 鈩，

本文編號：1811815