光交联法合成水凝胶的研究

合成了一种新型光敏性功能单体N -肉桂酰氧甲基丙烯酰胺 (CMMAM)及其与丙烯酸 (AA)的共聚物(CMMAM -AA) ,通过光交联法进一步合成水凝胶 .测定了CMMAM和CMMAM -AA聚合物的红外光谱 ,测定了水凝胶的DSC并对它的溶胀性能进行了初步研究     

光交联法合成新型温敏性水凝胶的研究

合成了丙烯酸β－羟基丙酯（β－HPAT）－N－肉桂酰氧甲基丙烯酰胺（CMMAM）共聚物，采用光交联法制备了温敏性共聚水凝胶，实验结果表明：共聚物交联程序随光照时间延长而增大，在一定温度范围内，水凝胶的溶胀率（SR）随温度升高而减小，表现出显著的温敏行为。     

Aam/Aac水凝胶对碱性藏花红染料的吸附特性研究

以丙烯酰胺(AAm)、丙烯酸(AAc)合成了单体配比分别为1，2、1／1、2，1的AAm/AAcc水凝胶，采用分光光度计法研究了此水凝胶对水溶性单价阳离子染料碱性藏花红的吸附特性，测定了它们的吸附动力学曲线和吸附等温线：探讨了水凝胶单体组成对该染料吸附性能的影响：并且用静电场理论解释了解吸后水凝胶更优的再吸附特性，研究表明，AAm，AAc水凝胶可作为染料污水处理中一种良好的吸附剂。     

控温相变免疫分析测定雌酮

通过热引发聚合与氧化还原引发聚合，合成水凝胶，作为雌酮全抗原(E1— BSA)载体；以异硫氰基灾光素标记雌酮的单克隆抗体(McAb)作为示踪剂，建立了控温相变竞争免疫分析测定雌酮(EI)的方法并应用于分析血清样品。实验表明：以热引发聚合合成的水凝胶为载体的荧光免疫分析方法具有更高的灵敏度，它的线性范围为10-700μg/L，检出限为1μg／L(n=10，3倍空白)。经水凝胶性质的比较(包括LCST、非特异性吸附、抗原与抗体反应时间及固定化抗原活性)，证明了热引发聚合的水凝胶较氧化还原引发聚合的水凝胶更适合于作为免疫分析的载体。     

pH敏感水凝胶聚甲基丙烯酸的超声合成

在超声作用下,以甲基丙烯酸为原料,N,N’-亚甲基双丙烯酰胺为交联剂,过硫酸钾为引发剂,自由基引发聚合制备了pH敏感水凝胶聚甲基丙烯酸,采用红外光谱(FT-IR)和扫描电镜(SEM)对水凝胶分子结构与性能进行表征.在此基础上,重点研究了超声合成对于水凝胶的溶胀性能、消溶胀性能等性质的影响.实验结果表明,超声作用下合成的聚甲基丙烯酸水凝胶溶胀动力学性能以及响应灵敏性均优于常规合成方法.     

聚乙二醇对PAMPS/PAM双网络水凝胶性能的影响

采用紫外光引发聚合制备了聚乙二醇(PEG)改性的聚(2-丙烯酰胺-2-甲基丙磺酸)/聚丙烯酰胺(PAMPS/PAM)双网络水凝胶.测定并比较了PEG改性前后双网络水凝胶的溶胀动力学以及单网络水凝胶中丙烯酰胺(AM)的吸收量;用扫描电子显微镜(SEM)观察了单网络水凝胶的结构;测定PEG改性前后双网络水凝胶的压缩及拉伸性能.结果表明,经PEG改性后的双网络水凝胶有较高的溶胀比;改性后单网络水凝胶更易吸收AM;改性后双网络水凝胶压缩形变率达到90%以上、拉伸形变率是未改性双网络水凝胶的2倍.     

磺化聚苯乙烯纳米微球-聚丙烯酰胺杂化水凝胶的制备及性能

首先通过乳液聚合法合成了聚苯乙烯(PS)微球,该微球经浓硫酸磺化后得到了磺化聚苯乙烯(SPS)微球;然后将合成的SPS微球作为多功能交联点加入丙稀酰胺(AAm)化学水凝胶网络中制备了SPS-PAAm杂化水凝胶。通过扫描电镜、透射电镜观察了SPS微球及杂化水凝胶的微观结构。研究了SPS微球对SPS-PAAm杂化水凝胶的凝胶分数、溶胀性能和力学性能的影响。结果显示:随着SPS微球用量的增加,SPS-PAAm水凝胶的凝胶分数先增加后降低,平衡溶胀度降低;SPS微球的加入能改善水凝胶的力学性能,随着SPS含量的增加,水凝胶的拉伸强度和能量损耗增加;SPS微球和PAAm分子链间存在物理相互作用。     

PVA改性PAMPS-PAM超高力学性能双网络水凝胶的制备

采用紫外光引发聚合制备了聚乙烯醇(PVA)改性的聚(2-丙烯酰胺基-2-甲基丙磺酸)-聚丙烯酰胺(PAMPS-PAM)双网络(DN)水凝胶.测定并比较了PVA改性前后PAMPS-PAM双网络水凝胶的溶胀动力学;通过扫描电子显微镜(SEM)观察了单网络水凝胶的结构;测定PVA改性前后PAMPS-PAM双网络水凝胶的压缩及拉伸性能.结果表明,经PVA改性后的PAMPS-PAM双网络水凝胶有较高的溶胀比;0.82%PVA用量的PAMPS-PAM双网络水凝胶在90%压缩形变率下仍保持完整、最大拉伸应力达到0.5 MPa,大幅提高PAMPS-PAM双网络水凝胶的力学性能.     

表面图案化磁性复合微球的原位制备与表征

采用反相悬浮聚合法合成了丙烯酸(AA)含量不同的N-异丙基丙烯酰胺-丙烯酸共聚物P(NIPAM-co-AA)微凝胶, 并以其作为微反应器, 通过原位外源沉积法制备了一系列微米级、表面具有图案化结构的SiO₂-Fe₃O₄-P(NIPAM-co-AA)磁性复合微球. 实验结果表明, 复合微球的表面结构与微凝胶的组成、Fe₃O₄和SiO₂的沉积量有关. 在微球表面进行修饰, 可得到表面带有氨基等官能基团的磁性复合材料. 将这种功能化磁性微球用于识别生物大分子并进一步用于生物医学领域具有重要的意义.     

温敏性P(MEO_2 MA-co-OEGMA-co-HMAM)自交联水凝胶的制备和性质

利用原子转移自由基聚合(ATRP)方法合成了新的温度敏感性聚合物聚(2-甲基-2-丙烯酸-2-(2-甲氧基乙氧基)乙酯-co-寡聚乙二醇甲醚甲基丙烯酸酯-co-N-羟甲基丙烯酰胺)[P(MEO2MA-co-OEGMA-coHMAM)]。红外光谱(FTIR)、核磁共振谱(1H NMR)和凝胶渗透色谱(GPC)对其结构进行了表征;利用透光率测定研究了共聚物的温度敏感性以及盐对其低临界溶解温度(LCST)的影响。将共聚物P(MEO2MA-coOEGMA-co-HMAM)链上的羟基分别转化为叠氮基和炔基后,在抗坏血酸钠和Cu SO4的催化条件下,通过温敏性共聚物P(MEO2MA-co-OEGMA-co-HMAM)链间点击自交联反应获得了温敏性水凝胶。凝胶形成流变动力学研究发现凝胶化作用在1 min之内发生,之后体系的储能模量(G')大于损耗模量(G″);通过SEM和溶胀性能分析表明,随着温度的升高水凝胶的孔径减小,导致水凝胶的保水量逐渐减小,证明了合成的凝胶具有温度敏感性;牛血清蛋白(BSA)和茴香脑分别作为亲水和疏水药物模型研究凝胶的药物体外持续释放。结果表明:在37oC时,载药凝胶对BSA释放率较大,释放速度较快。     

苝酰亚胺功能化聚苯乙烯乳胶粒水凝胶膜

将带有硼酸基团的苝酰亚胺荧光分子引入聚苯乙烯共聚乳胶粒表面,再将其嵌入聚丙烯酰胺水凝胶膜内,合成了对葡萄糖敏感的水凝胶膜。通过扫描电子显微镜、激光粒径分析仪对微球的外观形貌、单分散性进行表征,并用原子吸收光谱法间接测定了微球表面苝酰亚胺的含量,研究了苝酰亚胺功能化聚苯乙烯乳胶粒的紫外-可见吸收光谱图及其水凝胶膜的荧光性能。结果表明:苝酰亚胺功能化聚苯乙烯乳胶粒水凝胶膜经浓度逐渐增大的葡萄糖溶液浸泡后,其荧光强度降低,但发射峰位置不变。当葡萄糖浓度达到200 mmol/L时,其荧光淬灭效率为0.34。     

载银离子PLGA-PEG-PLGA温度敏感水凝胶的制备及体外抗菌性能

利用聚乙二醇(PEG 1000)引发乙交酯和 D,L-丙交酯开环共聚合, 制备了聚丙交酯乙交酯(PLGA)三嵌段共聚物(PLGA-PEG-PLGA)温敏水凝胶材料; 利用核磁共振氢谱( ¹H NMR)确定了产物的结构及组成. 通过还原硝酸银的方法制备银纳米粒子(AgNPs), 并将其与PLGA-PEG-PLGA三嵌段共聚物水凝胶混合, 制得新型AgNPs/PLGA-PEG-PLGA复合水凝胶; 对该复合水凝胶的相关性能进行了表征. AgNPs/PLGA-PEG-PLGA复合水凝胶仍然具有温敏性能, 随着温度升高可发生溶胶-凝胶的相转变; 还可以持续释放银纳米粒子, 从而发挥抗菌性能. 体外细胞实验结果表明, AgNPs/PLGA-PEG-PLGA复合水凝胶具有良好的生物相容性, 未见明显细胞毒性, 是具有应用前景的新型复合水凝胶.     

Synthesis of poly(sorbitan methacrylate) hydrogel by free-radical polymerization

Hydrogels are materials with the ability to swell in water through the retention of significant fractions of water within their structures. Owing to their relatively high degree of biocompatibility, hydrogels have been utilized in a host of biomedical applications. In an attempt to determine the optimum conditions for hydrogel synthesis by the free-radical polymerization of sorbitan methacrylate (SMA), the hydrogel used in this study was well polymerized under the following conditions: 50% (w/v) SMA as monomer, 1% (w/w) alpha, alpha'-azo-bis(isobutyro-nitrile) as thermal initiator, and 1% (w/w) ethylene glycol dimethacrylate as cross-liking agent. Under these conditions, the moisture content of the polymerized SMA hydrogel was higher than in the other conditions. Moreover, the moisture content of the poly(SMA) hydrogel was also found to be higher than that of the poly(methyl methacrylate [MMA]) hydrogel. When the Fourier transform-infrared spectrum of poly(SMA) hydrogel was compared with that of poly(MMA) hydrogel, we noted a band at 1735-1730/cm, which did not appear in the Fourier transform-infrared spectrum of poly(MMA). The surface of the poly(SMA) hydrogel was visualized through scanning electron microscopy, and was uniform and clear in appearance.     

聚(4-乙酰基丙烯酰乙酸乙酯-co-丙烯酸)水凝胶的溶胀动力学以及温度敏感性研究

通过分子结构设计, 合成了疏水性单体4-乙酰基丙烯酰乙酸乙酯(AAEA), 并以该单体与丙烯酸(AA)进行自由基溶液共聚, 制备了P(AAEA-co-AA)新型温度敏感性水凝胶. AAEA的¹H NMR及FT-IR分析表明, 该单体主要以烯醇式结构存在; P(AAEA-co-AA)的FT-IR分析发现, PAAEA与PAA之间存在较强烈的氢键作用, 使得AAEA烯醇异构体中的C—O伸缩振动吸收峰移向了低波数处. 对冷冻干燥后凝胶的电镜分析发现, 当AAEA用量较高时, 由于凝胶内部分子链段的疏水聚集, 各部分溶胀度以及溶胀速度不均一而使得凝胶表面粗糙不平. 采用DSC对凝胶的体积相转变进行了研究, 结果表明, 该水凝胶的体积相转变温度(VPTT)在48.2至61.8 ℃之间, 并且随着AAEA用量的减小, 凝胶的VPTT逐渐增加. 对该新型温度敏感性水凝胶在去离子水中的溶胀动力学研究发现, 当AAEA用量高于4.6 g时, 凝胶属于Fick凝胶; 反之凝胶则属于非Fick凝胶. 该水凝胶在去离子水中具有良好的温度敏感性, 当外界温度低于VPTT时, 凝胶能保持溶胀状态; 而当外界温度高于VPTT时, 凝胶的平衡溶胀度迅速下降, 表现为温度敏感性. 进一步研究发现, 凝胶组成不仅会影响凝胶的VPTT, 而且会影响凝胶温度敏感性的强弱.     

A pH-sensitive Modified Polyacrylamide Hydrogel

Intelligent hydrogels which have the capability to respond to small external stimulus changes, such as temperature1, pH2, photo field3, and antigen4, have attracted significant attention from both academia and industry. pH-sensitive polymers are produced …     

Hydrogel behavior of a sugar-based gelator by introduction of an unsaturated moiety as a hydrophobic group

The new sugar-based gelators 1 and 2 were synthesized, and their gelation abilities were evaluated in organic solvents and in water. Compound 1 gelates both water and organic solvents whereas 2 gelates only organic solvents. Superstructural difference between hydrogel 1 and organogel 2 was investigated by CD, TEM, AFM, 1H NMR and XRD. Hydrogel 1 displays a well-developed helical ribbon structure with 20-150 nm diameter and a length of several hundred microm whereas organogel 2 shows a twisted fiber structure of diameter 20 nm. CD measurements of hydrogel 1 and organogel 2 indicate that hydrogel 1 maintains a well-ordered chiral structure whereas organogel 2 maintains a relatively disordered chiral structure. The 1H NMR and XRD results suggest that the hydrophobic interaction in hydrogel 1 are relatively weak, with a relatively small region interdigitated between lipophilic alkyl groups. In addition, upon irradiation at 254 nm wavelength, hydrogel 1 reveals a red coloration at 540 nm. These results indicate that the self-assembled hydrogel 1 was polymerized by UV-irradiation. The intensity of the CD spectrum of the polymerized hydrogel markedly decreased. This result indicates that upon polymerization the highly ordered chiral structure of hydrogel 1 changes to a disordered molecular packing structure.     

医用聚丙烯酰胺水凝胶理化性能测试

测试了医用聚丙烯酰胺水凝胶产品的pH值、折射率、重金属含量、红外光谱、化学热稳定性和丙烯酰胺单体残留量等主要理化性能，重点研究了样品中残留单体丙烯酰胺的高效液相色谱分析法。     

Hydrogel Nanocomposite as a Synthetic Intra-Ocular Lens Capable of Accommodation

A hydrogel nanocomposite was designed, synthesized, and evaluated for use as an auto-focusing intra-ocular lens. The hydrogel scaffold was composed of a monomer-free, thiol that contained polyacrylamide (5%), which was allowed to gel in the presence of nanoparticles at pH 7.4, 25°C. The nanoparticles consisted of a proteo-mimetic polyacrylamide nanogel (∼42 nm), bovine serum albumin (BSA) (∼6 nm), and hydrophilized silica (∼3 nm). The extent of nanoparticle loading increased with decreasing particle size. The elastic modulus increased with increasing loading of the proteo-mimetic nanogels and BSA, and it decreased with hydrophilized silica. In this investigation, the hydrogel that contained silica was the most promising class of nanocomposite hydrogels with properties comparable to that of a young porcine lens. A nanocomposite that consisted of 10% hydrogel scaffold and 24% hydrophilized silica (elastic [E] modulus of ∼1.0 kPa and refractive index [RI] of 1.42) was injected into a pre-evacuated porcine lens capsular bag. The composite lens was evaluated in a custom-designed four-arm radial stretcher, and its force-time spectrum was characterized by time constants of 60 ± 8.9 and 800 ± 32 ms. These results were comparable to a young porcine lens (E Modulus of 1.2 kPa; RI of 1.4105; time constants of 48.3 ± 0.58 and 668 ± 24.6 ms, respectively)     

Cellulosic-based hydrogel from biomass material for removal of metals from waste water

Abstract

Cellulose and carboxymethyl cellulose (CMC), prepared from rice straw, were used for hydrogel preparation, separately or in a mixture of both of them in a ratios of 1:1, 1:4, 1:9, 2:3 and 3:7 (by weight).They were polymerized with partially neutralized acrylic acid (AA) in the presence of potassium persulphate, as initiator, and vinylsulphone (VS), as cross-linker. Moreover, glutaraldehyde, N,N-methylene bis acrylamide (MBA) and Epichlorohydrin (ECH) were used as cross-linker for the mixture of 1:1 of Cellulose: CMC. The mechanism of the polymerization was studied and the resulted hydrogels were characterized for their appearances, yields percentage, and water absorbencies. The Fourier transform infrared spectroscopy (FT-IR) and XRD analysis were also investigated for the hydrogel samples. Since the textile industry produces large volumes of wastewaters which contain hazardous compounds such as dyes, heavy metals like Cu(II), and surfactants, so we aimed in this research to use the hydrogel samples for Cu²⁺ absorption that can be presented in the wastewater. The FT-IR spectrum, before and after absorption, indicated that the prepared hydrogels were able to absorb the Cu²⁺. The Cu²⁺ ions can be recovered and dried to be reused again as well as the hydrogel samples can be available again for reuse.