耐高温低伤害清洁水性稠化剂的制备及性能

以丙烯酰胺、丙烯酸、十八烷基二甲基烯丙基氯化铵和十八烷基甲基丙烯酸酯为原料制备了一种疏水缔合聚合物(AAOS)，再使用低分子醇(乙二醇、丙三醇、正丙醇)、表面活性剂(椰子油脂肪酸二乙醇酰胺、十二烷基硫酸钠)、聚乙二醇(PEG)、聚乙烯醇缩丁醛(PVB)和疏水缔合聚合物(AAOS)配制了一种自交联耐高温清洁水性稠化剂(FPM-1)。对FPM-1的形貌、溶解性、表观黏度、耐盐性、流变性进行了测试。结果表明，质量分数为0.30%的FPM-1水溶液能显著增强AAOS聚合物分子间的疏水缔合交联作用，增大聚合物的流体力学体积。FPM-1水溶液为高黏弹性流体，悬砂性能好；质量分数为0.27%的AAOS在水中的溶解时间为7 min，最终表观黏度为90 mPa·s，质量分数为0.60%的FPM-1(具有等效聚合物含量)在水中的溶解时间仅需3 min，且最终表观黏度为165 mPa·s。在90℃、170 s^–1条件下剪切1 h后，质量分数为0.27%的AAOS水溶液的表观黏度为51 m Pa·s，质量分数为0.60%的FPM-1水溶液表观黏度为77 m Pa·s；质量分数为1.40%...     

孪尾疏水缔合水溶性聚合物P(AM/NaAA/DiC_8AM)水溶液的黏度行为

研究了胶束共聚法制备的孪尾疏水缔合水溶性聚合物P(AM/NaAA/D iC8AM)的水溶液的黏度行为。当疏水单元摩尔分数为0.05%~0.40%时,P(AM/NaAA/D iC8AM)在30℃、c(NaC l)=1.000 mol/L水溶液中的特性黏数[η]为2 149~367 mL/g、Huggins常数KH为0.220~3.90;随疏水单元摩尔分数增加,特性黏数[η]减少、KH增加。在矿化度为19 334μg/g的盐水溶液中,P(AM/NaAA/D iC8AM)的表观黏度随疏水单元摩尔分数的增加而增加、随剪切速率的增加而降低。随疏水单元摩尔分数的增加,临界缔合质量浓度降低;与后加的SDS[ρ(SDS)=0~6.0 g/mL]的疏水缔合作用增强,黏度增加的幅度增大。表观黏度随温度的变化也与疏水单元摩尔分数有关,当x(H)=0.3%、温度升至45℃左右时,出现最大值。在NaC l、CaC l2的离子强度分别为1.26×10-3~4.88×10-3mol/kg、1.07×10-4~5.28×10-4mol/kg的水溶液中,出现盐增黏现象。     

疏水缔合型聚合物P(AM/TA)溶液性质的研究

采用沉淀聚合法制备了疏水缔合型聚合物丙烯酰胺 /丙烯酸十四酯共聚物P(AM/TA)。研究了在链结构中引入不同疏水基团摩尔分数的共聚物的溶液性质。结果表明该共聚物在w(NaCl) =1 5 %的溶液中的黏度较之水溶液有较大提高 ,表现出明显的抗盐性质 ,而临界缔合质量分数和特性黏度均出现下降趋势。该聚合物是一种性能优异的疏水缔合型增稠剂。作者对共聚物溶液的黏度 -温度性质和剪切速度对溶液黏度的影响也进行了研究。     

疏水缔合聚合物减阻剂的合成及流变性能研究

采用疏水单体FW-12(物质的量比2∶1的丙烯酸十八酯与甲基丙烯酸十六烷基酯混合物)与丙烯酰胺(AM)、丙烯酸(AA)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)聚合得到水溶性疏水缔合聚合物减阻剂FHAPAM。考察了聚合过程放热特点,找出含疏水基团时聚合反应热量变化基本规律,用流变仪测定了FHAPAM水溶液的流变性能;芘探针实验探究了溶液的极性及变化规律;室内减阻实验测试其减阻性能。结果表明:FHAPAM聚合温度受疏水单体摩尔分数影响较大,存在明显的平台区,FHAPAM水溶液受剪切作用表现出强触变性;溶液极性随疏水单体摩尔分数的增加而降低,且第一振动带与第三振动带强度比值I1/I3的比值存在突变点;FHAPAM耐温性强于普通聚丙烯酰胺(PAM);疏水单体摩尔分数不同,储能模量(G')、损耗模量(G″)均表现出特殊性。FHAPAM低浓度时,减阻性能优良,其展现出作为滑溜水压裂液良好的应用前景。     

疏水缔合聚合物减阻剂的合成及流变性能

采用疏水单体FW-12(物质的量比2∶1的丙烯酸十八酯与甲基丙烯酸十六烷基酯混合物)与丙烯酰胺(AM)、丙烯酸(AA)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)聚合得到水溶性疏水缔合聚合物减阻剂FHAPAM。考察了聚合过程放热特点,找出含疏水基团时聚合反应热量变化基本规律,用流变仪测定了FHAPAM水溶液的流变性能;芘探针实验探究了溶液的极性及变化规律;室内减阻实验测试其减阻性能。结果表明:FHAPAM聚合温度受疏水单体摩尔分数影响较大,存在明显的平台区,FHAPAM水溶液受剪切作用表现出强触变性;溶液极性随疏水单体摩尔分数的增加而降低,且第一振动带与第三振动带强度比值I1/I3的比值存在突变点;FHAPAM耐温性强于普通聚丙烯酰胺(PAM);疏水单体摩尔分数不同,储能模量(G')、损耗模量(G″)均表现出特殊性。FHAPAM低浓度时,减阻性能优良,其展现出作为滑溜水压裂液良好的应用前景。     

疏水改性羟丙基胍胶(Hm-HPG)水溶液黏度行为研究

该文研究了疏水改性羟丙基胍胶(Hm-HPG)水溶液的黏度行为。结果表明:当Hm-HPG水溶液浓度超过临界缔合浓度cac后,溶液表观黏度(ηa)会迅速增加;水溶液中Hm-HPG质量分数为0.4%时,ηa随温度的升高经历升高-降低-平衡的变化过程,在20℃附近出现最大值;水溶液的ηa随NaCl、KCl和CaCl2加入量的增大不断增加,NaCl对溶液ηa增加的贡献最大,KCl次之,CaCl2最弱。当水溶液中Hm-HPG-R16和Hm-HPG-R12质量分数分别高于0.2%和0.3%时,十二烷基硫酸钠(SDS)与疏水聚合物存在着明显的相互作用。     

孪尾疏水缔合丙烯酰胺/丙烯酸钠/N,N-二己基丙烯酰胺共聚物制备条件的研究

采取先加碱共聚-共水解的方法合成了孪尾疏水缔合丙烯酰胺/丙烯酸钠/N,N-二己基丙烯酰胺共聚物[P(AM/NaAA/DiC6AM)],用傅里叶变换光谱、1H-核磁共振及容量分析法对其结构进行了表征.反应10 h转化率可达92%,之后增加缓慢.水解度主要受水解时间的影响,受疏水单元摩尔分数的影响较小.还研究了疏水单元摩尔分数、总单体质量浓度、DM质量浓度、(NH4)2S2O8质量浓度、温度、SMR对P(AM/NaAA/DiC6AM)水溶液的表观黏度的影响.     

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.     

表面活性剂对孪尾缔合聚合物水溶液表观黏度的影响

用黏度法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-二己基丙烯酰胺）[P（AM／NaAA／DiC6AM）]与十二烷基硫酸钠（SDS）、十六烷基三甲基溴化铵（CRAB）、OP-10的相互作用。结果表明,水溶液的表观黏度随SDS、CTAB质量浓度的增加急剧上升,超过一定浓度后水溶液黏度又急剧下降;黏度上升的幅度随疏水单体用量的增加、表面活性剂与疏水单体的摩尔比率（SMR值）的减小而增大;随水解度的增加,黏度上升的幅度较小。P（AM／NaAA／DiC6AM）的临界缔合浓度cac约为30g/mL,当加入SDS、CTAB时,能显著地降低。随OP-10质量浓度的增加,水溶液表观黏度几乎不变。表明P（AM／NaAA／DRAM）与SDS、CTAB的疏水缔合作用较强,而与OP-10的疏水缔合作用较弱。     

孪尾疏水缔合丙烯酰胺/丙烯酸钠/N,N-二己基丙烯酰胺共聚物水溶液的黏度行为

采用先加碱共聚-共水解方法制备了孪尾疏水缔合丙烯酰胺/丙烯酸钠/N,N 二己基丙烯酰胺共聚物[P(AM/NaAA/DiC6AM)],经容量滴定法测试,P(AM/NaAA/DiC6AM)的水解度=14 37%～15 80%,接近理论水解度15%。当x(疏水单元)=0 0641%～0 372%时,P(AM/NaAA/DiC6AM)在c(NaNO3)=1 000mol/L水溶液中的特性粘数[η]值为12 60～10 33dL/g、Huggins常数值为0 83～1 39。P(AM/NaAA/DiC6AM)在矿化度为19334μg/g盐水溶液中的表观黏度随疏水单元摩尔分数的增加而增加,随温度、剪切速率的增加而降低。在ρ(NaCl)=2～10g/dL、ρ(CaCl2)=0 2～1 0g/dL的水溶液中,出现盐增黏现象;且疏水单元摩尔分数越高,盐增黏效应越显著。P(AM/NaAA/DiC6AM)的疏水单元摩尔分数越高,与后加的SDS[ρ(SDS)=0～0 050g/dL]的疏水缔合作用越强,溶液的增黏效果越明显。     

Preparation and viscosity behavior of hydrophobically modified poly(vinyl alcohol) (PVA)

In this study, a novel series of water-soluble hydrophobically modified poly(vinyl alcohol) (PVA) is prepared by chemical modification of PVA, with the objective of investigating the polymer's rheological behavior for enhanced oil recovery applications. The solution viscosity of the polymer obtained is studied with respect to the polymer concentration, temperature, salinity, polymer modification, aging, shear rate, and polymer molecular weight. The solution viscosity of the PVA is greatly enhanced by the modification. The modified PVA exhibits a relatively high salt tolerance, typical of nonionic polymers, in the range of 0–7.0 wt % NaCl concentrations, and the viscosity of the polymer solution is relatively invariant with NaCl above 3.0 wt % NaCl concentration. Below 3 wt %, the viscosity shows a maximum then a minimum, an unusual behavior. Generally, the polymer exhibits an almost constant viscosity at high shear rates and a typical shear thinning behavior at low shear rates. In addition, increasing polymer concentration and molecular weight leads to an increase in the polymer solution viscosity. Moreover, the polymer exhibits smaller solution viscosity at a high temperatre, and a slight decrease in viscosity is also exhibited by the modified polymer with aging. Comparison of the viscosities of 18 polymer modifications indicates that the larger the numbers of hydrophobic groups (side chains) in the polymer structure, the smaller the viscosity. Moreover, the longer the hydrophobic groups (side chains) in the polymer structure, the greater the viscosity, if their number is small. © 1995 John Wiley & Sons, Inc.     

溶液共混法制备高强度淀粉基完全生物降解塑料薄膜

利用一步溶液共混法，将预糊化的淀粉糊与PvA溶液共混，用乙二醛进行交联，制备淀粉／聚乙烯醇（PVA）完全生物降解塑料薄膜。研究不同乙二醛和甘油的用量对薄膜性能的影响。薄膜的力学性能、热性能和微观形态表征表明，淀粉／PvA体系具有较好的相容性和较高的力学性能，薄膜的拉伸强度和断裂伸长率分别可达到28．52MPa和307．5％。     

Electrospinning of chitosan/poly(vinyl alcohol)/acrylic acid aqueous solutions

Chitosan bicomponent fibers were prepared via the electrospinning of chitosan/poly(vinyl alcohol)/acrylic acid aqueous solutions with different concentrations. With a 4% acrylic acid aqueous solution, when the chitosan/poly(vinyl alcohol) mass ratios were lower than 80/20, electrospinning nanofibers could be obtained. With a 90% acrylic acid aqueous solution, when the chitosan/poly(vinyl alcohol) mass ratios were less than 95/5, good nanofibers could be electrospun. The average diameter of the nanofibers gradually decreased, and its distribution became narrower as the poly(vinyl alcohol) concentration increased. Chitosan/poly(vinyl alcohol)/acrylic acid aqueous solutions could be electrospun at various concentrations by the adjustment of the chitosan and poly(vinyl alcohol) concentrations. The effects of the viscosity and conductivity of the blend solution on the morphologies of the fiber mats were also investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5692–5697, 2006     

含氯化钠的聚乙烯醇静电纺丝研究

研究了不同聚合度聚乙烯醇与少量氯化钠盐混合物水溶液的静电纺丝,并与单纯聚乙烯醇水溶液的静电纺丝进行了对比。利用扫描电镜观察纤维的形态、直径变化。结果表明:聚乙烯醇水溶液中加入少量氯化钠,由于离子的作用可以使喷射流表面电荷密度增大,静电纺丝可得到比单纯聚乙烯醇更细的纳米纤维。     

An interpolymer anionic composite reverse osmosis membrane derived from poly(vinyl alcohol) and poly(styrene sulfonic acid)

An interpolymer anionic composite membrane for reverse osmosis was prepared from poly(vinyl alcohol) and poly(styrene sulfonic acid). The effects of composition of a casting solution, heat-curing periods, and casting thickness on the reverse osmosis performance of resulted membranes have been examined. A mixture of water and ethyl alcohol (12/7, wt %) was found to be a proper solvent for casting an interpolymer membrane on the supporter. The composite membrane was formed by casting the polymer solution in ultrathin film on a microporous polypropylene supporter, evaporating the solvent, and heat-curing at 120°C for a proper period. the optimum composition of a casting solution was as follows: wt % of poly(vinyl alcohol)/poly(styrene sulfonic acid)/solvent was 3/2/95. The membrane heat-cured at 120°C for 2 h has a good performance for reverse osmosis, viz., water flux of 9.1–28.4 L/m².h at salt rejection level of 88.1–93.4% under applied pressure of 80 kg/cm² with 0.5% NaCl aqueous solution. The formation mechanism of a water-insoluble membrane was discussed.     

低残余醛的聚乙烯醇缩丁烯醛的制备与应用

以聚乙烯醇(PVA)和丁烯醛为主要原料,合成了聚乙烯醇缩丁烯醛(PVBE)。讨论了反应时间、丁烯醛用量、HCl含量和PVA浓度等因素对PVBE黏度的影响。结果表明:200 mL PVA(质量浓度大于5%)溶液中加入0.75～1.5 mL的HCl,当丁烯醛用量(ρ)在0.15～0.25之间,通过调节以上因素,室温反应120～216 h可制得适宜黏度的PVBE水溶液;同时介绍了PVBE中去除残余醛的两种方法;最后研究了低残余醛PVBE作为增稠剂、保护胶体在聚醋酸乙烯(PVAc)乳液中的应用。     

Studies on syntheses and permeabilities of special polymer membranes: 24. Permeation characteristics of poly(vinylidene fluoride) membranes

The permeation characteristics of poly(vinylidene fluoride) membranes were investigated by changing the preparation conditions of the membranes, the composition of the casting solution, membrane thickness, time of heat treatment and temperature, etc.; and by changing the permeation conditions, operating temperature, the feed concentration, and the feed solute, etc. Aqueous solutions of poly(vinyl alcohol) and poly(ethylene glycol) were used as feed. The permeation characteristics were influenced significantly by the change of the above conditions and were dependent on the structure of resulting membrane, the viscosity of feed, the form of polymer molecules in aqueous solution, and the concentration polarization of polymer solute molecules onto the membrane surface. The permeation through very swollen membranes (ca. 85% in water content) followed the viscous flow.     

Water–ethanol permseparation by pervaporation through photocrosslinked poly(vinyl alcohol) composite membranes

Water–ethanol permselectivity was investigated by pervaporation through composite membranes which were prepared by coating photocrosslinkable poly(vinyl alcohol) containing pendant styrylpyridinium group (0.86–3.93 mol %) on porous films. These membranes were water-permselective, and the selectivity was dependent on the state of membranes; namely, incorporation ratio of styrylpyridinium group on poly(vinyl alcohol), molecular weight of the base polymer, coating thickness of a photopolymer, etc. Photocrosslinkable styrylpyridinium group showed, of course, the ionic character by a pyridinium moiety to work on permseparation of water effectively as well as preventing the dissolution of membranes by crosslinking. Membranes based on the higher molecular weight poly(vinyl alcohol) (P = 1700) gave the higher permselectivity of water in general than those of lower molecular weight (P = 500) one. Swelling of the polymers reached 160%, and permeation rate through the membranes increased with the increase of swelling. Selective diffusion of water was found to take place in swelling, and to play a part in the water-permseparation through the membranes.     

Electroactive characteristics of interpenetrating polymer network hydrogels composed of poly(vinyl alcohol) and poly(N‐isopropylacrylamide)

An interpenetrating polymer network (IPN) composed of poly(vinyl alcohol) (PVA) and poly(N‐isopropylacrylamide) (PNIPAAm) was prepared by the sequential IPN method. The equilibrium swelling ratio and bending behavior under electric fields of the IPN hydrogel were measured in an aqueous NaCl solution. The IPN exhibited a high equilibrium swelling ratio, in the range 280–380%. When the IPN in aqueous NaCl solution was subjected to an electric field, the IPN showed significant and quick bending toward the cathode. The IPN hydrogel also showed stepwise bending behavior, depending on the electric stimulus. In addition, the ionic conductivity of the IPN hydrogel was measured using dielectric analysis, and its conductive behavior followed the Arrhenius equation. The conductivity of the IPN hydrogel and the activation energy for the form of the IPN were 1.68 × 10^?5 S/cm at 36°C and 61.0 kJ/mol, respectively. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 890–894, 2003     

Investigation of Poly(vinyl alcohol)/Pluronic F127 Physical Gels

The application of Pluronic F127 as injectable gel-forming solution is limited by poor mechanical properties. The purpose of this study was to develop low viscosity formulations at ambient temperature that undergo a transition to gel under physiological conditions. Mixtures of Pluronic F127 and poly(vinyl alcohol) with different compositions were prepared in aqueous solutions and their in-situ gelation was investigated by dynamic light scattering and rheology. The results obtained for different formulations showed synergistic effects of polymer mixtures in aqueous media and their properties can be tuned by varying polymer concentration, system composition or changing temperature.