纳米SiO2改性疏水缔合聚合物基的合成及性能评价

本文以丙烯酰胺(AM)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)和丙烯酸(AA)为亲水单体,十六烷基二甲基烯丙基氯化铵(CDMAAC)为疏水单体,在纳米SiO_2的存在下,以EDTA/VA044/过硫酸铵/抗坏血酸为引发剂,通过自由基聚合法,合成了具有核壳结构的纳米SiO_2改性疏水缔合聚合物。分别通过红外光谱和扫描电镜对聚合物的结构及微观形态进行了表征,对聚合物的分子量和不同浓度的聚合物溶液的表观黏度进行了测定。结果表明,聚合物有较好的疏水缔合作用,纳米SiO_2的引入,使得聚合物水溶液的表观黏度、耐盐性能及耐酸碱性能得到明显的改善。     

乙醇浓度及温度响应型智能高分子的制备及其性能

采用自由基聚合法将亲水单体N,N-二甲基丙烯酰胺(DMAA)和疏水单体甲基丙烯酸丁酯(BMA)分别与N-异丙基丙烯酰胺共聚,从而制备聚(N-异丙基丙烯酰胺-co-N,N-二甲基丙烯酰胺)高分子(PND)和聚(N-异丙基丙烯酰胺-co-甲基丙烯酸丁酯)高分子(PNB)。考察了共聚高分子在水溶液中的相转变温度以及在相转变温度以下对乙醇溶液浓度的响应特性。实验证明亲水单体DMAA和疏水单体BMA能够很好地调节PN共聚高分子的相转变温度和乙醇响应浓度。     

期刊文献

<正>双尾型丙烯酰胺类疏水缔合共聚物的合成与表征姜峰,蒲万芬,杜代军,任强,荆雪琪摘要:通过光引发自由基聚合的方式,将双尾型丙烯酰胺类疏水单体(N-苯乙基-N-十四烷基甲基丙烯酰胺,PETMAM),与丙烯酰胺(AM)、丙烯酸(AA)等水溶性单体进行共聚,制备出双尾型疏水缔合水溶性共聚物(DTHAP),来解决丙烯酰胺类聚合物耐温抗盐性以及稳定性差的难题。通过测定聚合物溶液的表观黏度作为评价其性能的主要手段,考察了丙烯酸加量、盐、表面活性剂(SDS)含量、疏水单体含量等因素对聚合物性能的影响,从而确定了比较理想的反应条件。实验中发现:     

聚甜菜碱型疏水聚合物的合成及性能评价

以苯甲酰氯、丙烯酸、N,N-二甲基-1,3-丙二胺和氯乙酸为主要原料,合成了一种甜菜碱型功能单体丙烯酰胺丙基甜菜碱。丙烯酰胺丙基甜菜碱单体、丙烯酰胺、疏水单体进行三元共聚,得到聚甜菜碱型疏水聚合物,对聚合物溶液的抗盐性能进行了评价。结果表明,新型聚甜菜碱型疏水聚合物溶液具有优良的盐增稠性能。     

荧光探针研究P(AM/NaAA/DiC_8AM)在水溶液中的缔合行为

以芘为荧光探针研究了孪尾疏水缔合水溶性聚合物聚(丙烯酰胺/丙烯酸钠/N,N-二正辛基丙烯酰胺)[P(AM/NaAA/D iC8AM)]在二次蒸馏水、c(NaC l)=1 mol/L水溶液中的荧光光谱。当x(疏水单体)=0.10%~0.40%、表面活性剂与疏水单体的摩尔比(SMR)为20~70、x(丙烯酸)=20%~40%、ρ(聚合物)=5~50 g/mL时,I1/I3值为1.76~1.25。表明疏水基团间存在疏水缔合相互作用,且随疏水单体用量、聚合物质量浓度及介质极性的增加,和丙烯酸用量、SMR值的减少,芘的I1/I3值降低,疏水缔合作用增强。     

一种含苯环结构的温敏聚合物溶液的驱油作用

从温敏聚合物的增粘作用、降低油水界面张力、乳化作用及微观驱油过程,研究含苯环疏水单体、亲水单体和温敏单体的三元共聚温敏聚合物驱油作用。研究认为,温敏聚合物在高温高盐条件下溶液的增粘主要是依靠其结构中亲、疏水基团的疏水缔合的作用;温敏聚合物具有降低油水界面张力、乳化和提高洗油能的作用。     

一种含苯环结构的温敏聚合物溶液的驱油作用

从温敏聚合物的增粘作用、降低油水界面张力、乳化作用及微观驱油过程,研究含苯环疏水单体、亲水单体和温敏单体的三元共聚温敏聚合物驱油作用。研究认为,温敏聚合物在高温高盐条件下溶液的增粘主要是依靠其结构中亲、疏水基团的疏水缔合的作用;温敏聚合物具有降低油水界面张力、乳化和提高洗油能的作用。     

耐温抗盐耐剪切型滑溜水降阻剂的制备探讨

针对耐温、抗盐、耐剪切型降阻剂的制备提出一些具体的思路。列举了一些可以提高耐温抗盐性的单体,例如含有强电解质基团的单体,包括乙烯基磺酸、丙烯基磺酸、乙烯基苯磺酸、2-丙烯酰胺基-2-甲基丙磺酸;还有含有环状结构的单体,包括N-乙烯基吡咯烷酮、壳聚糖、乙烯基糖苷、乙烯基β-环糊精、N-烯丙基咪唑、丙烯酰吗啉等。另外,乳液型疏水缔合丙烯酰胺共聚物既具有良好的溶解性也具有较好的抗剪切性。     

耐温抗盐耐剪切型滑溜水降阻剂的制备探讨

针对耐温、抗盐、耐剪切型降阻剂的制备提出一些具体的思路。列举了一些可以提高耐温抗盐性的单体,例如含有强电解质基团的单体,包括乙烯基磺酸、丙烯基磺酸、乙烯基苯磺酸、2-丙烯酰胺基-2-甲基丙磺酸;还有含有环状结构的单体,包括N-乙烯基吡咯烷酮、壳聚糖、乙烯基糖苷、乙烯基β-环糊精、N-烯丙基咪唑、丙烯酰吗啉等。另外,乳液型疏水缔合丙烯酰胺共聚物既具有良好的溶解性也具有较好的抗剪切性。     

矿化度对疏水缔合聚合物溶液溶解时间的影响研究

疏水缔合聚合物是在亲水的聚丙烯酰胺大分子主链上引入少量疏水基团合成的新型水溶型聚合物。其有耐温耐盐的良好特性。但是疏水基的引入降低了聚合物的水溶性,增加了溶解时间。本文以渤海某油田地层水的离子构成作为参考,通过配制不同矿化度溶液来溶解疏水缔合聚合物,探索矿化度对疏水缔合聚合物溶液粘度及溶解时间的影响,并从原理上解释了出现这些现象的原因。最终发现,随着矿化度升高,疏水缔合聚合物溶液粘度降低,溶解时间增大。这种现象是由于矿化度升高,溶液中电解质增多,溶液极性增强,影响了疏水缔合聚合物分子的展开和缔结。     

Hydrophobically associating polymers and their interactions with rod-like micelles

Several families of anionic and cationic hydrophobically associating acrylamide-based copolymers have been synthesized. This study focuses on the characterization in aqueous environments of water-soluble copolymers in which low levels of alkyl, i.e. methylene, units are incorporated into the polymer chain structure. These hydrophobic monomers have built-in surfactant character; therefore, no non-polymerizable surfactants are required in the preparation of these copolymer materials. These hydrophobically associating copolymers are shown to possess both polyelectrolyte and hydrophobic character, especially as the ionic strength of the solution is varied. The results confirm that, even at low concentrations of hydrophobe (typically ≤ 1 mol%), interesting solution properties are observed, i.e. enhanced rheology as compared to its non-associating parent, marked time-dependent rheology at low shear rates, ‘anti-polyelectrolyte effect’ in high-ionic-strength solutions and the ability to interact preferentially with hydrophobically associating rod-like micelles. These latter materials are capable of forming highly viscoelastic solutions themselves. The rheological properties of these latter solution mixtures are very sensitive to the fraction of each component in the mixture and to the length of the alkyl chain copolymerized into the acrylamide chain backbone.     

疏水缔合水溶性聚合物的分子结构对疏水缔合的影响

疏水缔合水溶性聚合物是水溶性聚合物中含有少量疏水基团,在水溶液中疏水基团由于范德华力聚集在一起,使水溶液具有良好的增粘作用和抗盐耐温性。对该类聚合物的分子结构对疏水缔合的影响作了综述。     

Preparation of ion-containing elastomers by emulsion copolymerization of dienes with olefinic sulfonic acid salts

Procedures were developed for the emulsion copolymerization of either butadiene or isoprene with several different water-soluble monomers containing sulfonic acid salt groups, primarily with sodium styrenesulfonate, for the preparation of ionomer elastomers. By the use of a nonionic surfactant and a two-component redox initiator, which was based on a water-soluble reducing agent and a hydrophobic peroxide, copolymers with sufficient amounts of the ionic monomer could be prepared. Unusual effects of conversion on rate, copolymer composition, and molecular weight were observed and attributed to special effects caused by the ionic monomers. The copolymers were soluble in mixed hydrocarbon–alcohol solvent systems.     

疏水缔合改性丙烯酰胺共聚物的合成

采用自由基胶束聚合法合成了丙烯酰胺（AM）/丁基苯乙烯（BS）/2-甲基-2-丙烯酰胺基丙磺酸钠（NaAMPS）疏水缔合水溶性共聚物PASA,PASA避免了目前疏水缔合聚合物溶液热稳定性差的问题.研究得到了适宜的反应条件,包括NaAMPS、BS和引发剂加量相对于单体总量的摩尔分数分别为10%、2.5%和0.07%,总单体在水里的质量分数为10%,SDS在水里的质量分数为6.0%,反应温度50℃,pH=6～7,反应时间12 h.采用以上反应条件得到PASA的临界缔合质量浓度为0.05 g·dL^-1,对应的水溶液表观黏度为283 mPa·s,质量浓度为0.1 g·dL^-1的水溶液表观黏度为1020 mPa·s.采用元素分析、UV、FT-IR和¹HNMR证实了共聚物的分子结构;DSC分析表明了共聚物分子链中存在疏水嵌段.     

Synthesis and swelling behaviour of hydrophobically modified responsive polymers in dilute aqueous solutions

New series of associating polymers were synthesised in order to investigate opposite behaviours of hydrophobically modified water-soluble polymers and thermoresponsive water-soluble polymers carrying LCST stickers. On the basis of a poly(acrylic acid) backbone, amino-terminated poly(N-isopropylacrylamide), poly(ethylene oxide-co-propylene oxide) and/or dodecyl chains were grafted following a reaction of condensation activated by carbodiimide. Two homologous series of well-defined single grafted and double grafted copolymers were obtained, with double grafted chains containing both C12 and LCST grafts. The dilute solution properties of these copolymers were carefully studied by capillary viscometry. At low salt concentration and below the LCST of the grafts, the swelling properties of macromolecular chains are controlled either by intramolecular associations between hydrophobes, excluded volume effect exerted by hydrophilic grafts or by a balance between these opposite interactions. The deswelling of macromolecular chains, induced by hydrophobic interactions, is amplified at higher ionic strength and more particularly above the transition temperature of the side chains.     

疏水缔合型聚丙烯酰胺的研究进展

疏水缔合型聚丙烯酰胺（HAPAM）是疏水缔合水溶性聚合物（HAWSP）中研究最多的一种,它可以通过共聚反应在聚丙烯酰胺中引人少量疏水基团而得到。由于疏水基团的憎水作用,共聚物水溶液中产生分子间缔合作用,从而具有独特的流变性能。在石油开采、污泥处理、涂料工业及生物医学等方面具有良好的应用前景。综述了国内外学者在HAPAM的合成、性质和应用等方面的研究进展,并对其发展前景进行了展望。     

Rheological evaluation of synthesized template‐hydrophobically modified acrylamide based copolymers in brine

The newly hydrophobically modified associating acrylamide‐based copolymers were prepared by the inverse miniemulsion polymerization method in order to investigate the copolymers rheological and associating properties in water and brine solutions. Dimethyldodecane (2‐acrylamidopropyl) ammonium bromide (DDPAB) was synthesized and used as a hydrophobic monomer and was later copolymerized with acrylamide in the presence of poly(acrylic acid‐co‐maleic acid) and various molecular weights of poly(acrylic acid) as templates. The chemical compositions and functional groups of the resulting hydrophobic monomer and copolymers were characterized using the ¹H nuclear magnetic resonance and Fourier transform‐infrared spectroscopy. According to the studies on the solutions viscosity behavior, incorporation of small amount of hydrophobic monomer improved the thickening properties due to the intermolecular hydrophobic association. The apparent viscosity of the copolymers with a template was much greater than those prepared without a template. The molecular weight of the template strongly influenced the thickening behaviors of the copolymers. A template copolymer with 1 mol % of a hydrophobic monomer was the one most efficient. The addition of electrolyte saline improved the polarization of the solutions and enhanced the thickening ability. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43588.     

Synthesis, structure and properties of hydrophobically associating polymers

Hydrophobically modified water-soluble polymers have recently become the subject of extensive research because of their use as aqueous viscosity modifiers in oil recovery and latex paint systems. In this study, poly(acrylamide) samples modified with small amounts of a hydrophobic monomer (ethylphenylacrylamide) have been prepared by free radical copolymerization using an aqueous micellar process in which the use of a surfactant ensures the solubilization of the hydrophobe. The copolymers exhibit improved thickening properties with respect to homopoly(acrylamide) analogs due to intennolecular hydrophobic associations. The aqueous solution-copolymer properties strongly depend on the amount of surfactant used in the synthesis. The differences observed between the samples are directly related to the copolymer microstructure, that is to a more or less block distribution of the hydrophobic units. The interactions in aqueous solution of a surfactant (sodium dodecylsulfate (SDS)) with these copolymers have been examined. A strong increase in viscosity is observed upon the addition of SDS below its critical micelle concentration, owing to the formation of mixed micelles of SDS and hydrophobic monomers. The complex rheological behavior observed is explained in terms of the balance between inter and intrachain liaisons. The effects of hydrolysis on the hydrophobic interactions are also discussed.     

Rheological behaviors and structure of hydrophobically associating AM–SMA copolymers synthesized by microemulsion polymerization

A series of hydrophobically associating copolymers of acrylamide and hydrophobic stearyl methacrylate as comonomers were prepared by microemulsion polymerization. The rheological properties of the copolymers in aqueous solution depended on the content of hydrophobic monomer, initiator amount, surfactant concentration, the copolymer concentration and the addition of salt. The hydrophobically associating copolymers showed good temperature, shear, and salt resistance with the critical aggregation concentration around 0.6 g dL^?1. In addition, the apparent viscosities of hydrophobically associating copolymer solutions are increased remarkably by the addition of a small amount of NaCl and CaCl₂, respectively. FTIR and ¹H-NMR spectra indicate the structure of hydrophobically associating copolymers. The shear-thinning behavior of hydrophobically associating copolymer makes it useful in enhanced oil recovery and drilling fluids.     

Structure,surface tension,and rheological behaviors of hydrophobically associative polyacrylamides by self-emulsified microemulsion polymerization

Hydrophobically associating copolymers using acrylamide (AM), acrylic acid (AA), and Styrene (St) as comonomers were successfully prepared by self-emulsified microemulsion polymerization, in which low-molecular-weight AM/AA/St copolymers as surfactant and AM as cosurfactant. The structure and chemical composition of AM/AA/St copolymers were characterized by Fourier transform infrared, nuclear magnetic (NMR), and differential scanning calorimeter. The content of PSt in the copolymers is determined by ¹H nuclear magnetic resonance spectra, suggesting that the self-made polymer surfactant can disperse uniformly the St monomers to improve the copolymerization efficiency. Furthermore, the polymerization mechanism of the self-emulsified microemulsion method is explored preliminarily. During the synthesis of the copolymers, the purified copolymer solution is obtained in one step without using a small molecular emulsifier such as sodium dodecyl sulfate, in order to avoid the complicated post-treatment process of the small molecular emulsifier. The copolymers revealed good hydrophobic association properties and low surface tension.