超高分子量高阳离子度AM-DMC-DAC三元共聚物的合成及其絮凝性能

在较高阳离子含量下,合成了丙烯酰胺(AM)-甲基丙烯酰氧乙基三甲基氯化铵(DMC)-丙烯酰氧乙基三甲基氯化铵(DAC)三元共聚物.考察了引发剂浓度、单体浓度、反应体系pH及链转移剂对聚合反应产物黏度的影响.结果表明:该三元共聚物的特性黏度可以达到36 dL/g,溶解性能良好,阳离子度高,絮凝性能优良.     

环糊精包结作用下水溶液共聚合制备疏水改性阳离子聚丙烯酰胺及其絮凝效果研究

在水溶液中制备了甲基环糊精(Me-β-CD)/疏水单体2-苯氧乙基丙烯酸酯(POEA)的包结物(1a)。利用紫外-可见光谱及核磁共振波谱等检测手段研究了Me-β-CD与POEA的包合作用,并对包合物的结构、性能进行了表征和分析。同时在水溶液中引发丙烯酰胺(AM)、阳离子单体丙烯酰氧乙基三甲基氯化铵(DAC)以及1a的均相共聚合得到疏水修饰的阳离子聚丙烯酰胺P(AM-DAC-POEA),实现了用绿色方法合成高效高分子絮凝剂的目的,并对该高分子对高岭土模拟污水的絮凝效果进行了考察。     

丙烯酰胺-丙烯酰氧乙基三甲基氯化铵共聚合的竞聚率测定

采用溶液聚合制备了新型阳离子共聚物--聚丙烯酰胺基-丙烯酰氧乙基三甲基氯化铵(P(AM-DAC)),采用滴定法测定了其阳离子共聚物的阳离子度.分别采用Fineman-Ross 法、Kelen-Tudos 法和Yezrielev-Brokhina-Roskin法计算出单体竞聚率.结果表明,KT法和YBR法计算较为准确,丙烯酰氧乙基三甲基氯化铵和丙烯酰胺的竞聚率分别为rDAC=0.383 5,rAM=2.286 4.     

含Gemini表面活性剂结构单元的新型两亲聚电解质的合成及聚集行为

分别将Gemini型单体1,3-双(二甲基十四烷基溴化铵)-2-丙烯酰氧基丙烷(14G)或1,3-双(二甲基十六烷基溴化铵)-2-丙烯酰氧基丙烷(16G)与丙烯酰氧乙基三甲基氯化铵(DAC, D)共聚合反应, 合成了新型含Gemini表面活性剂结构单元的两亲性阳离子聚电解质(D14G和D16G). 采用稳态荧光、电导、动态光散射及透射电镜等手段研究了这些聚电解质在水溶液中的聚集行为. 结果表明, 临界聚集浓度(CAC)随着Gemini型表面活性剂单元含量的增加而减小, 同时随着Gemini型表面活性剂单元中疏水碳链长度的增加而降低. 这些聚电解质在水溶液中同时存在分子内和分子间两种类型的聚集体, 而且碳链越长, 形成分子内聚集体的倾向越强. 随着Gemini表面活性剂单元含量的增加, D14G溶液中聚集体的流体动力学半径(Rh)也有所增大, 而D16G溶液中的聚集体的流体动力学半径(Rh) 却略有减小.     

聚(N-对丙烯酰氧苯甲酰氧基)丁二酰亚胺的合成及其共聚物与血清蛋白的固定化

新的丙烯酸活性酯,N-(对甲基丙烯酰氧苯甲酰氧基)丁二酰亚胺(MBOSu)及N-(对丙烯酰氧苯甲酰氧基)丁二酰亚胺(ABOSu)单体分别由对甲基丙烯酰氧基苯甲酸(MBA)、对丙烯酰氧基苯甲酸(ABA)与N-羟基丁二酰亚胺(HOSu)在环已基羰二亚胺存在下经偶联反应合成。MBOSu及 ABOSu 容易进行均聚合及与MBA或ABA进行共聚合而得到相应的反应性聚合物。P(MBOSu-MBA)共聚物是一个较好的固定化蛋白质的载体。它极易与抗血清(驴抗人A·B·O混合血清)或正常人 A·B·O混合血清反应,形成一种具有较高免疫活性的固定化免疫吸附剂。     

以PAAS为模板AM与DMC的模板共聚合反应

在水溶液中以聚丙烯酸钠(PAAS)为模板,进行了丙烯酰胺(AM)与2-甲基丙烯酰氧乙基三甲基氯化铵(DMC)的共聚合反应。研究了其聚合动力学,并对模板共聚物的序列结构进行了表征,最后对其进行了絮凝性能评价。结果表明:聚合反应符合模板聚合Ⅰ型机理,聚合反应速率分别与单体浓度和引发剂浓度的1.63和1.64次方成正比,此种共聚物与无模板参与聚合的普通共聚物相比具有更长的DMC序列长度,对高岭土悬浮液的絮凝沉降速率优于普通共聚物。     

聚丙烯酸修饰咔唑的电化学聚合及表征

合成了侧链带有咔唑的N-丙烯酰氧己基咔唑(MACZ),通过自由基聚合得到聚N-丙烯酰氧己基咔唑(PMACZ),在四氢呋喃含10%三氟化硼乙醚与四氟化硼四丁基胺的混合电解质溶液中,直接阳极氧化PMACZ获得自支撑交联网状的聚(聚N-丙烯酰氧己基咔唑)(PPMACZ)薄膜.PPMACZ薄膜具有良好的氧化还原性和热稳定性,电导率为1.34×10-5S·cm-1.1HNMR和红外光谱表明PMACZ二次聚合反应发生在咔唑单元的3,6位上,荧光光谱表明PPMACZ薄膜是一种良好的蓝色发光材料.     

烷基步长对聚丙烯酸修饰咔唑电聚合的影响

合成了含有不同烷基链取代的N-丙烯酰氧癸基咔唑(MACZ10)和N-丙烯酰氧十二烷基咔唑(MACZ12), 通过自由基聚合得到聚N-丙烯酰氧烷基咔唑(PMACZ). 分子量分析表明, 随着烷基链长度的增加, 聚合物分子量减小, 分布变宽. 荧光光谱表明, 随着烷基链长度的增加, 聚合物在353 nm处的发射峰逐渐减弱. 在四氢呋喃和体积分数为10%三氟化硼乙醚与四氟化硼四丁基胺的混合电解质溶液中, 直接阳极氧化PMACZ获得自支撑交联网状的聚(聚N-丙烯酰氧烷基咔唑)(PPMACZ)薄膜. PPMACZ薄膜具有良好的氧化还原活性、热稳定性和蓝色发光性能, 聚合物氧化还原可逆性随着烷基链长的增加而增加, 且发射峰变宽.     

超支化聚酰胺-胺破乳剂的合成及应用

以N-丙烯酰-1,2-乙二胺盐酸盐(ADE)合成为基础,通过ADE的Michael加成反应制备阳离子超支化聚合物聚N-丙烯酰-1,2-乙二胺盐酸盐(HADE),并对其结构进行了表征。研究表明,50℃下,HADE破乳剂(质量浓度为200 mg/L)对含煤油质量分数5%的水包油(O/W)煤油乳液的除油率可高达95.6%,显示了产品在乳液破乳除油方面良好的发展前景。     

纳米银与基体P(AMPS-MMA)的相互作用研究

在无引发剂和还原剂的条件下超声辐射双原位合成出纳米银/2-丙烯酰氨基-2-甲基丙磺酸与甲基丙烯酸甲酯共聚物[P(AMPS-MMA)]复合物.TEM表明,纳米银粒子的粒径5~15nm,均匀地分散在聚合物基体中;UV-Vis表明,超声时间影响纳米银的粒径大小及粒径分布;FT-IR、UV-Vis和荧光光谱表明纳米银与基体P(AMPS-MMA)之间存在一定的化学作用力;XPS证明了纳米银与基体P(AMPS-MMA)的作用力为纳米银与聚合物中酯基氧原子之间通过配位作用形成的化学作用力.     

Microstructure of un-neutralized hydrophobically modified alkali-soluble emulsion latex in different surfactant solutions

At low pH conditions and in the presence of anionic, cationic, and nonionic surfactants, hydrophobically modified alkali-soluble emulsions (HASE) exhibit pronounced interaction that results in the solubilization of the latex. The interaction between HASE latex and surfactant was studied using various techniques, such as light transmittance, isothermal titration calorimetry, laser light scattering, and electrophoresis. For anionic surfactant, noncooperative hydrophobic binding dominates the interaction at concentrations lower than the critical aggregation concentration (CAC) (C < CAC). However, cooperative hydrophobic binding controls the formation of mixed micelles at high surfactant concentrations (C > or = CAC), where the cloudy solution becomes clear. For cross-linked HASE latex, anionic surfactant binds only noncooperatively to the latex and causes it to swell. For cationic surfactant, electrostatic interaction occurs at very low surfactant concentrations, resulting in phase separation. With further increase in surfactant concentration, noncooperative hydrophobic and cooperative hydrophobic interactions dominate the binding at low and high surfactant concentrations, respectively. For anionic and cationic surfactant systems, the CAC is lower than the critical micelle concentration (CMC) of surfactants in water. In addition, counterion condensation plays an important role during the binding interaction between HASE latex and ionic surfactants. In the case of nonionic surfactants, free surfactant micelles are formed in solution due to their relatively low CMC values, and HASE latexes are directly solubilized into the micellar core of nonionic surfactants.     

Aggregation Behavior of Mono-endcapped Hydrophobically Modified Poly(sodium acrylate)s in Aqueous Solution

Titration microcalorimetry and steady-state fluorescence spectroscopy have been used to study the aggregation of mono-endcapped hydrophobically modified poly(sodium acrylate)s in aqueous solution. Polymers with molecular weights varying between 800 and 31,700 were synthesized by radical polymerization using an initiator and chain transfer agent. The resulting polymers form hydrophobic microdomains in aqueous solutions. The following conditions were applied: no salt and pH 5 and 9, respectively; 1 M sodium citrate and pH 9. At pH 5 the critical aggregation concentration (CAC, the concentration at which microdomains are formed) increases with increasing molecular weight of the polymers. The concentration range for aggregation is about 0.2-2.4 mM. At pH 9 the carboxylic acid groups are deprotonated and electrostatic repulsions are introduced; therefore the concentration for aggregation rises to about 80 mM. Interestingly, in case of polymers having M(n)<1400 the CAC decreases with increasing molecular weight due to a counterion-concentration gradient toward the hydrophobic microdomain. Near the microdomain the counterion binding is increased, reducing the electrostatic repulsions and allowing for lower aggregation concentrations. In the presence of 1 M sodium citrate this anomalous trend is suppressed to a large extent; since the overall counterion binding is increased and the CAC is lower. The concentration for aggregation is then in the same range as at pH 5 in the absence of salt. Copyright 2000 Academic Press.     

P(AM-NVP-DMDA)疏水缔合水溶性共聚物的研究

采用自由基水溶液共聚合法制备了Ｐ（ＡＭ－ＮＶＰ－ＤＭＤＡ）疏水缔合水溶性共聚物。对共聚物的溶液性能进行了研究,包括盐效应、粘温关系、流变性能、热稳定性、与碱、表面活性剂的相互作用、稀溶液性质等。共聚物分子中由于引入了较多的疏水基团而具有较强的疏水缔合效应,在聚合物浓度较低时具有较高粘度。ＮＶＰ结构单元的引入可适当提高共聚物溶液的热稳定性。对共聚物溶液的电镜分析结果表明,在其水溶液中存在着微相分离结构,它对共聚物溶液的增粘起着重要作用。     

The Interaction Between N–Isopropylacrylamide-Acrylic Acid-Ethyl Methacrylate Thermosensitive Polymers and Cationic Surfactants

The interaction between cationic surfactants and isopropylacrylamide-acrylic acid-ethyl methacrylate (IPA:AA:EMA) terpolymers has been investigated using steady-state fluorescence and spectrophotometric measurements to assess the effect of the polymer composition on the aggregation process and terpolymers’ thermosensitivities. Micropolarity studies using pyrene show that the interaction of cationic surfactants with IPA:AA:EMA terpolymers occurs at surfactant concentrations much smaller than that observed for the pure surfactant in aqueous solution. The critical aggregation concentration (CAC) values decrease with both the hydrocarbon length of the surfactant and the content of ethyl methacrylate. These results were interpreted as a manifestation of the increasing contribution of attractive hydrophobic and electrostatic forces between negatively charged polymer chains and positively charged surfactant molecules. The increase of ethyl methacrylate in the copolymers lowers the CAC due to the larger hydrophobic character of the polymer backbone. The cloud point determination reveals that the lower critical solution temperatures (LCST) depend strongly on the copolymer composition and surfactant nature. The binding of surfactants molecules to the polymer chain screens the electrostatic repulsion between the carboxylic groups inducing a conformational transition and the dehydration of the polymer chain.     

表面活性剂对纤维素接枝共聚物溶液粘度性质的影响

研究了阴离子十二烷基硫酸钠(SDS)、阳离子十六烷基三甲基溴化铵(CTAB)和非离子聚乙二醇辛基苯基醚(OP)等三种不同类型的表面活性剂对疏水化水溶性两性纤维素接枝共聚物(CGAO)溶液粘度性质的影响.结果表明,在SDS和OP的临界胶束浓度(cmc)附近，CGAO溶液粘度最大，SDS引起CGAO粘度的变化大于OP；即使在CTAB的cmc附近，随着CTAB浓度的增加，CGAO的粘度一直呈下降趋势；非疏水改性的纤维素接枝共聚物的溶液粘度随SDS或CTAB浓度的增加而下降，但几乎不随OP浓度的增大而变化.此外，通过凝胶渗透色谱法测得的保留时间证实了SDS、CTAB和OP与CGAO之间的疏水缔合作用.     

改性聚丙烯酰胺水溶液的疏水缔合性质

合成了一种疏水缔合水溶性聚丙烯酰胺共聚物,使用荧光光谱法并结合紫外及流变性实验,对制备的疏水缔合水溶性聚丙烯酰胺共聚物在水溶液中形成疏水微区、超分子聚集体及空间网络结构进行了研究,并用扫描电子显微镜证实了溶液中网络结构的存在.     

树枝聚醚改性聚丙烯酰胺和阴离子表面活性剂的缔合行为

采用粘度法、荧光探针技术和^1H NMR驰豫和自扩散方法，研究了树枝聚醚疏 水改性丙烯酰胺共聚物(PDAM)和十二烷基硫酸钠(SDS)在水溶液中的相互作用．这 种共聚物含有少量的树枝聚醚，具有疏水性，容易和SDS发生相互作用，在表面活 性剂浓度远低于临界胶束浓度(cmc)的情况下，生成混合胶束状聚集体．它们的缔 合行为和溶液性质明显地取决于表面活性剂的浓度，随着聚合物溶液中加入SDS， 溶液粘度发生急剧变化，并在较低的表面活性剂浓度处出现很大的最高点．荧光和 ^1H NMR测定结果表明，这是由于在不同SDS浓度范围内，PDAM/SDS形成的聚集体结 构不同的缘故．     

Polyelectrolyte-surfactant complexes with long range order

Mixtures of carboxymethyl cellulose (CMC) or hydrophobically modified CMC with an oppositely charged surfactant (benzyldimethyltetradecylammonium chloride) in water were prepared. When the global polymer concentration is 0.18% by weight and the surfactant content is high enough, a precipitate with hexagonal order is formed. The precipitate composition shows practically constancy in its water content and a slight diminution in polymer concentration when the global surfactant content is varied between 0.9 and 23 wt%. The lattice parameter in this phase decreases when the polymer/surfactant ratio in the phase increases; this variation is faster with CMC than with the hydrophobically modified CMC. In this way electrostatic and hydrophobic interactions are far from being additive. From the extrapolation to infinite dilution, the global interaction seems to depend on the substitution degree in the polymer. Additionally, the comparison between the radius at the polar-apolar interface in the cylinders and the lattice parameter as a function of polymer/surfactant ratio in the hexagonal phase is compatible with some of the alkyl chains belonging to the hydrophobically modified CMC being present in the aqueous zone.     

Gelation of spontaneously formed catanionic vesicles by water soluble polymers

The gelation of two spontaneously formed charged catanionic vesicles by four water soluble polymers was systematically studied by tube inversion method and rheology. Eight phase maps were successfully documented for the catanionic vesicle–polymer mixtures. The experimental results, as represented by the relaxation time and the storage modulus at 1 Hz, revealed that the catanionic vesicle–polymer interactions at play were of electrostatic and hydrophobic origin. Firstly, no association between charged catanionic vesicles and the polymer without charge/hydrophobic modification was observed due to lack of both electrostatic and hydrophobic effects. Secondly, hydrophobic interactions accounted for the association between the hydrophobically modified polymer without charge and charged catanionic vesicles with hydrophobic grafts of the polymer inserting in the catanionic vesicle bilayer. Thirdly, the positively charged polymer without hydrophobic modification could interact with negatively charged catanionic vesicles through electrostatic force on one hand but could not interact with positively charged catanionic vesicles on the other hand. Finally, the positively charged polymer with hydrophobic modification could interact both electrostatically and hydrophobically with negatively charged catanionic vesicles, resulting in the formation of strong gels. The hydrophobic interaction might even overcome the unfavorable electrostatic interaction between the positively charged vesicles and the polymer with positive charge/hydrophobic modification.     

疏水改性聚电解质的荧光探针光谱

流水改性聚电解质或聚皂（PolysoaP）是在亲水性聚电解质的侧链或主链上键合少量的强流水性基团的聚合物l'，'］流水基团一般采用长链烷基（通常碳原子数大于刚＊一、也有用硅氧烷、氟碳化合物进行疏水改性问由干这种聚合物分子链上带有两性亲媒基团，因此，又被称为高分子表面