【摘要】：聚乙二醇(PEG)含親水鏈段,可以提高吸水性能。聚乙二醇基水凝膠具有良好的吸水保水性、生物相容性,可在人體內(nèi)使用,不會(huì)引起炎癥反應(yīng),而且能被機(jī)體迅速排出體外而不產(chǎn)生任何毒副作用。聚乙烯醇,是一種用途相當(dāng)廣泛的水溶性高分子聚合物。聚乙烯醇(PVA)具有很多優(yōu)良的特性,例如有良好的成膜性和抗拉強(qiáng)度,耐沖擊、絕緣性好、耐磨、強(qiáng)力粘接性和良好的平滑性。聚N-異丙基丙烯酰胺(PNIPAm)水凝膠是目前研究最多的溫敏水凝膠,屬于典型的熱縮型水凝膠,其最低臨界溫度(LCST)在32 ℃接近人體溫度。若調(diào)節(jié)聚合物骨架中的親水組分和疏水組分,LCST還可以上下變動(dòng)。本實(shí)驗(yàn)分為兩個(gè)部分,第一部分,利用異氰酸酯基容易與羥基反應(yīng)的特性,通過(guò)接枝共聚法,首先合成了端基為異氰酸酯基團(tuán)(IPDI)的聚乙二醇(PEG)預(yù)聚物(PEG-IPDI),再將聚乙烯醇和預(yù)聚物反應(yīng),合成PEG-IPDI-PVA水凝膠。進(jìn)一步加入鋰藻土、蒙脫土納米填料,探究納米填料對(duì)PEG-IPDI-PVA水凝膠性能的影響。結(jié)果表明,隨鋰藻土的加入溶脹率明顯提高,說(shuō)明鋰藻土的加入改善了水凝膠的內(nèi)部結(jié)構(gòu)和物理、化學(xué)性能。而在35 ℃到40 ℃時(shí),溶脹率增長(zhǎng)迅速,改善了此類材料的溫敏性能。蒙脫土的加入可有效提高聚合物的機(jī)械性能。第二部分,以低分子量的聚乙二醇甲基丙烯酸酯(PEGMA)和N-異丙基丙烯酰胺(PNIPAm)為主要單體,亞甲基雙丙烯酰胺(BIS)為交聯(lián)劑,過(guò)硫酸鉀(KPS)和四甲基乙二胺(TEMED)為引發(fā)劑,采用自由基共聚法成功合成了 P(NIPAm-PEGMA)水凝膠。并添加鋰藻工作為增強(qiáng)劑制備了系列納米雜化凝膠。對(duì)該系列凝膠研究表明,PEGMA和鋰藻土的加入可以改變PNIPAm凝膠的內(nèi)部結(jié)構(gòu)和性能,能夠改善凝膠的力學(xué)性能,也會(huì)影響水凝膠的溫敏性。
[Abstract]:Polyethylene glycol (PEG) contains hydrophilic chain segment, which can improve the water absorption performance. Polyethylene glycol-based hydrogels have good water absorption and water retention, biocompatibility, can be used in human body, do not cause inflammation, and can be quickly expelled by the body without any toxic side effects. Polyvinyl alcohol is a widely used water-soluble polymer. Polyvinyl alcohol (PVA) has many excellent properties, such as good film forming and tensile strength, impact resistance, good insulation, wear resistance, strong adhesion and good smoothness. Poly (N-isopropylacrylamide) (PNIPAm) hydrogel is the most studied thermosensitive hydrogel at present. It belongs to the typical thermal shrinkage hydrogel, and its lowest critical temperature (LCST) is close to the human body temperature at 32 鈩，

本文編號(hào)：2445100