發(fā)布時間：2018-05-17 02:23

  本文選題：聚丙烯酰胺水凝膠 + 自修復(fù)水凝膠　； 參考：《中國科學(xué)技術(shù)大學(xué)》2017年碩士論文

【摘要】：聚丙烯酰胺(PAM)水凝膠在藥物控釋、組織工程、物質(zhì)分離、工農(nóng)業(yè)、石油化工、機(jī)械器件等方面都有著廣泛的應(yīng)用前景。但是傳統(tǒng)方法制備的PAM水凝膠力學(xué)性能不佳,缺乏功能基團(tuán),使其應(yīng)用范圍受到極大的限制,因此設(shè)計和制備新型結(jié)構(gòu)的聚丙烯酰胺水凝膠及其功能化一直以來都是水凝膠領(lǐng)域的熱門研究課題。本論文工作針對不同使用環(huán)境中傳統(tǒng)PAM水凝膠強(qiáng)度弱、易被破壞的缺點,設(shè)計制備了三種不同交聯(lián)形式的高強(qiáng)度PAM基水凝膠,即溫敏性自修復(fù)聚丙烯酰胺水凝膠、原位熱交聯(lián)型聚丙烯酰胺水凝膠以及"活性"聚合物納米粒子增強(qiáng)聚丙烯酰胺水凝膠,并對其力學(xué)性能進(jìn)行了表征。具體研究內(nèi)容如下:1.乳液聚合法一步制備溫敏性自修復(fù)聚丙烯酰胺水凝膠。首先合成了側(cè)基易于形成氫鍵的乙烯基共聚單體5-乙酰氨基丙烯酸戊酯(AAPA),然后將AAPA、丙烯酰胺(AM)和甲基丙烯酸十二烷基酯(DM)按一定比例與含有乳化劑十二烷基硫酸鈉(SDS)的水溶液混合形成乳液,以過硫酸銨(APS)和四甲基乙二胺(TEMED)為引發(fā)劑體系,室溫下一步反應(yīng)得到自修復(fù)聚丙烯酰胺水凝膠,該凝膠的彈性模量高達(dá)400 Pa。疏水鏈段在疏水締合作用下發(fā)生相分離形成可控的物理交聯(lián)點,當(dāng)溫度升高到70℃時,凝膠會發(fā)生凝膠-溶膠轉(zhuǎn)變。將斷裂的凝膠斷面接觸,2 min內(nèi)斷裂的凝膠能夠回復(fù)到原始強(qiáng)度95%以上。2.原位熱交聯(lián)型聚丙烯酰胺水凝膠的制備。在四氫呋喃中通過自由基溶液聚合制備AM和Y-甲基丙烯酰氧丙基三甲氧基硅烷(MPS)的無規(guī)共聚物P(AM-co-MPS),將所得共聚物溶于水,能夠形成粘度為4～10mPa·s的聚合物水溶液,當(dāng)P(AM-co-MPS)共聚物水溶液濃度大于10 wt%,且共聚物中MPS的含量高于19 wt%時,可以在50～70 °C下原位交聯(lián)形成凝膠,強(qiáng)度高達(dá)7500 Pa。3."活性"聚合物納米粒子增強(qiáng)聚丙烯酰胺水凝膠的制備。首先在甲醇中通過可逆加成-斷裂鏈轉(zhuǎn)移(RAFT)聚合制備兩親性嵌段共聚物聚丙烯酸-b-聚苯乙烯(PAA-b-PS),經(jīng)過在水中透析可自組裝形成"活性"聚合物囊泡,乙二醇二甲基丙烯酸酯(EGDMA)溶脹進(jìn)入囊泡的疏水微區(qū),使得聚合物囊泡成為多功能的交聯(lián)點,與丙烯酰胺共聚形成高強(qiáng)度水凝膠。研究了不同AM、EGDMA以及納米粒子濃度對凝膠強(qiáng)度的影響,結(jié)果表明這種聚合物納米粒子增強(qiáng)的水凝膠表現(xiàn)出優(yōu)異的機(jī)械性能,壓縮強(qiáng)度和拉伸強(qiáng)度分別高達(dá)7 MPa和2 MPa,而且具有良好的抗疲勞性能。
[Abstract]:Polyacrylamide (PAM) hydrogel has a wide application prospect in drug controlled release, tissue engineering, material separation, industry and agriculture, petrochemical, mechanical devices and so on. However, the PAM hydrogels prepared by traditional methods have poor mechanical properties and lack of functional groups, so their application scope is greatly limited. Therefore, the design and preparation of novel polyacrylamide hydrogels and their functionalization have been a hot research topic in hydrogel field. In this paper, three kinds of high strength PAM hydrogels with different cross-linking forms were designed and prepared, that is, thermo-sensitive self-repairing polyacrylamide hydrogels, aiming at the weakness of traditional PAM hydrogels with weak strength and easy to be destroyed in different application environments. In situ thermal crosslinked polyacrylamide hydrogels and "active" polymer nanoparticles were used to enhance polyacrylamide hydrogels and their mechanical properties were characterized. The specific contents of the study are as follows: 1. Temperature-sensitive self-repairing polyacrylamide hydrogels were prepared by one-step emulsion polymerization. A vinyl copolymerization monomer, 5-acetylamyl aminoacrylate (AAPAN), which is easy to form hydrogen bonds on the side group, was synthesized at first. Then, AAPA, AM) and DMMA) were prepared in a certain proportion with the emulsifier dodecyl sulphuric acid. The aqueous solution of sodium disodium (SDS) is mixed to form an emulsion. Using ammonium persulfate (APS) and tetramethyl ethylenediamine (TEMED) as initiators, a self-repairing polyacrylamide hydrogel was obtained at room temperature. The elastic modulus of the gel was as high as 400 Pa. The hydrophobic chain segment is separated by phase separation under hydrophobic association to form a controllable physical crosslinking point. When the temperature rises to 70 鈩，

本文編號：1899482