共查询到17条相似文献,搜索用时 140 毫秒
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以马来酸酐(MAH)和β-环糊精(β-CD)为原料,N,N-二甲基甲酰胺(DMF)为溶剂,经醇解反应合成了乙烯基β-环糊精单体(MAH-β-CD)。以丙烯酰胺(AM)、2-甲基-2-丙烯酰胺基丙磺酸(AMPS)、二甲基二烯丙基氯化铵(DMDAAC)及合成的MAH-β-CD为单体,通过自由基水溶液聚合法制备了一种四元共聚物(PAADM)。通过单因素变量法得出四元共聚物最优制备条件为:m(MAH-β-CD)∶m(AM)∶m(AMPS)∶m(DMDAAC)=1∶69∶20∶10,引发剂用量为0.4%(占单体总质量),反应温度45℃,单体质量分数20%,反应时间6 h,p H=7。通过红外光谱、紫外可见吸收光谱及核磁氢谱对共聚物进行了结构表征,表明合成的聚合物即为目标产物。聚合物的性能评价结果表明,质量分数为0.8%的PAADM在盐酸(质量分数20%)中的酸溶时间为100 min;PAADM与PDMC稠化酸比较结果显示,PAADM稠化酸有较好的热稳定性及缓速性能,并且该稠化酸抗剪切性能和配伍性良好。 相似文献
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以丙烯酰胺(AM)、丙烯酸(AA)、环糊精改性超支化功能单体(MAH-β-CD-HPEA)、甜菜碱(DEPS)为原料合成了四元共聚物PADAH。考察了引发剂质量分数、AM与AA质量比、DEPS与MAH-β-CD-HPEA质量比对聚合物溶液黏度的影响。得到的最佳合成条件为:AM与AA的质量比为2∶1(共占单体总质量的85%),DEPS与MAH-β-CD-HPEA的质量比为14.5∶0.5(共占单体总质量的15%),引发剂质量分数为0.3%。性能研究表明,该共聚物的质量浓度为2000 mg/L时,溶液黏度可达643 mPa·s,3500 r/min剪切20 s后黏度保留率高于80%;90℃时,PADAH的黏度为237m Pa·s,黏度保留率为37.5%,均优于未加MAH-β-CD-HPEA的甜菜碱型聚合物(PADA)和普通部分水解聚丙烯酰胺(HPAM)。 相似文献
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以丙烯酸(AA)、甲基丙烯磺酸钠(MAS)、马来酸酐接枝β-环糊精(MAH-β-CD)和甲基烯丙基聚氧乙烯醚(APEG)为原料,通过水溶液自由基共聚制备了β-CD改性聚羧酸系减水剂(MPC)。考察了反应物摩尔比、引发剂用量、反应时间及反应温度对减水剂性能的影响。当单体摩尔比n(AA)∶n(MAS)∶n(MAH-β-CD)∶n(APEG)=5∶0.5∶0.1∶1、引发剂过硫酸铵(APS)用量为单体总质量的5%、反应温度为90℃、反应时间为5 h时,所得减水剂性能较好。应用结果表明,掺MPC后水泥净浆流动度可达306 mm、初凝时间为440 min、减水率达32.2%。SEM和强度测试结果表明,掺有MPC的水泥石的结构更加紧密匀质,孔洞更加微小,有利于混凝土后期结构的发展。 相似文献
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以N,N′-亚甲基双丙烯酰胺(MBA)为交联剂,以甲基丙烯酸(MA)和N-异丙基甲基丙烯酰胺(NIPMAM)作为聚合单体合成具有温度及p H双重敏感性的水凝胶。研究了MBA的用量与水凝胶溶胀过程的影响。在25℃和55℃下分别研究水凝胶在酸性和碱性条件下的去溶胀动力学和再溶胀动力学过程。 相似文献
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《云南化工》2018,(11)
以丙烯酸钾(AAK)、丙烯酰胺(AM)为单体,过硫酸铵(APS)为引发剂,维持单体总质量分数恒定但改变其中两种单体分别的质量分数,采用自由基溶液聚合的方法,合成出六组新型聚丙烯酸钾/丙烯酰胺凝胶,并以相同质量分数合成纯聚丙烯酰胺凝胶作为对照组。通过红外光谱测试、抗压强度测试与溶胀测试,表征各组凝胶的化学结构、抗压强度与溶胀特性。研究表明,单体、交联剂、引发剂的质量分数分别为15%、0.8%和0.1%,当丙烯酸钾质量分数为5%,丙烯酰胺质量分数为10%时,合成的聚丙烯酸钾/丙烯酰胺凝胶压缩强度为0.378 MPa,15°C时在去离子水中溶胀5.7 h后溶胀比达到336.7 g/g,在七组凝胶中,性能最优。 相似文献
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文章通过N-异丙基丙烯酰胺(NIPAAm)同马来酸酐(MAH)改性的β-环糊精发生共聚反应得到一种新型温敏性共聚物,表征确认其结构,并对其温敏性能进行了研究。结果:由于环糊精单元的引入,产品较NIPAAm均聚物有更高的最低临界共溶温度(LCST),环糊精单元在产品中所占的比例越多,其LCST值越大,并且在高pH和低离子浓度环境下,产品有更高的LCST。 相似文献
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This study has developed a novel route for the synthesis of the thermoresponsive core-shell nanoparticles that consist of the magnetite core and the poly(N-isopropylacrylamide) (poly(NIPAAm) shell in aqueous medium. Magnetic nanoparticles (MNPs) were coated first with oleic acid (OA) and then vinyl carboxylic acid-β-cyclodextrin (MAH-β-CD). The OA-MNPs and the MAH-β-CD-MNPs showed mono-dispersion in n-hexane and aqueous medium, respectively. NIPAAms were successfully polymerized from the vinyl double bonds of the MAH-β-CD MNPs and cross-linked with N, N-methylenebisacrylamide (MBA) to make the stable thermoresponsive core-shell morphology with the MNP core and the poly(NIPAAm) shell (poly(NIPAAm)-MNP). The aqueous solutions dispersed with poly(NIPAAm)-MNPs showed magnetic heating due to a superparamagnetic property, and the poly(NIPAAm) shell shrank above its LCST temperature. The combination of these properties are potentially important in the targeted delivery of therapeutic agents in vivo, hyperthermic treatment of tumors, magnetic resonance imaging (MRI) as a contrasting agents, tissue repair, immunoassay, cell separation, biomagnetic separation of biomolecules, etc. 相似文献
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Yu-Yang LiuXiao-Dong Fan 《Polymer》2002,43(18):4997-5003
A reactive β-Cyclodextrin (β-CD) based monomer carrying vinyl carboxylic acid functional groups was synthesized via reaction of β-CD with maleic anhydride (MAH) in N,N-dimethylformamide (DMF) at 80 °C. By copolymerization of the monomer with N-isopropylacrylamide (NIPA), a novel hydrogel, poly(NIPA-co-MAH-β-CD) with pH and temperature sensitivities plus molecular inclusion function, was obtained using free radical polymerization in aqueous solution. The hydrogel's composition was determined by element analysis and infrared spectroscopy. Equilibrium swelling ratio (ESR) of hydrogels was tested under different environment of pH, temperature and ionic strength. The results indicated that ESR of hydrogels presents marked variations following the change of experimental conditions used. 相似文献
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《分离科学与技术》2012,47(15):2342-2351
Molecular imprinted polymer (MIP MAA-β-CD) with 2,4-dichlorophenol (2,4-DCP) and methacrylic acid functionalized β-cyclodextrin (MAA-β-CD) as the template molecule and the functional monomer, respectively, was prepared and used in molecular imprinted-solid phase extraction (MISPE) for the extraction of phenols (2,4-dichlorophenol, 2-chlorophenol, 4-chloro-3-methylphenol, 4-chlorophenol, 2,4,6-trichlorophenol, and 2-nitrophenol) from water samples. The MISPE method was optimized prior to the determination using gas chromatography coupled with a flame ionization detector (GC-FID). Under the optimized conditions, the MIP MAA-β-CD sorbent showed good linearity (0.01-12 mgL?1), low limits of detection (0.14-0.75 µgL?1), and good repeatability (RSD 2.3-3.6%, n = 3). Good recoveries were obtained in the range of 97-115% for tap water and between 88-103% for river water. The developed MIP MAA-β-CD SPE was then compared with other adsorbents. The unique properties of β-CD and presence of imprinted cavities explains the higher extraction recoveries obtained for phenols when using MIP MAA-β-CD SPE. 相似文献
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A new β-cyclodextrin (β-CD) methacrylated monomer was synthesized from the reaction of β-CD, glycidyl methacrylate. Based on inclusion character of β-CD, a series of hydrogels were prepared by irradiating the mixtures of β-CD methacrylate monomer (β-CD-Met), poly(ethylene glycol) monoacrylate, poly(ethylene glycol)diacrylate, fumaric acid monoethyl ester-functionalized poly(lactic-co-glycolic) acid, 1-vinyl-2-pyrrolidone, N,N′-methylene bisacrylamide, and the photoinitiator. Gel percentages and equilibrium swelling ratios (%) of hydrogels were investigated. It was observed that equilibrium-swelling ratio increased with increasing β-CD-Met content in the hydrogel composition. SEM images demonstrated that β-CD-Met-based hydrogel have lots of voids on the fractured surface. In this study, ibuprofen (IBU) which is capable of forming inclusion complex with β-CD was chosen. For the hydrogel with maximum CD content, the IBU drug loading was found as 9 mg/g dry gel. It can be concluded that the inclusion complex-formation capability of β-CD moiety increases the drug release by improving the aqueous solubility of hydrophilic drugs. 相似文献
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以b-环糊精(β-CD)、2-羟丙基-β-环糊精(HP-β-CD)和4-乙烯吡啶(4-VP)为功能单体,以氟比洛芬为模板分子,以环氧氯丙烷和乙二醇二甲基丙烯酸酯为交联剂,采用本体聚合法制备分子印迹聚合物(MIPs),对氟比洛芬与功能单体的相互作用和MIPs的结构进行了表征,比较了3种MIPs对氟比洛芬的吸附性能. 结果表明,β-CD, HP-β-CD和4-VP与氟比洛芬之间以较强的相互作用形成复合物,通过交联、聚合形成聚合物,以HP-β-CD作功能单体所得聚合物印迹效果最佳,具有较强的特异性吸附能力,印迹因子和特异性吸附率分别为1.79和38.92%,分子印迹机制是β-CD的锥筒包结作用和羟丙基的亲和作用形成印迹空穴. 相似文献