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。     

水溶性疏水缔合聚合物单体的合成

水溶性疏水缔合聚合物含有大量的亲水基团和少量的疏水基团,疏水基团间的疏水缔合作用使这种聚合物具有独特的增粘、抗剪切、耐温和耐盐的溶液性能,通常采用亲水单体和疏水单体共聚制备这类聚合物。对常用亲水单体AMPS及各类疏水单体如季铵盐不饱和单体AMPDAC和DAMAB、长链丙烯酸酯,N-烷基丙烯酰胺和N-芳烷基丙烯酰胺的合成进行了综述。     

孪尾疏水缔合丙烯酰胺/丙烯酸钠/N,N-二丁基丙烯酰胺共聚物的合成与性能

以十二烷基硫酸钠(SDS)为表面活性剂,丙烯酰胺(AM)的水溶液为连续相,N,N-二丁基丙烯酰胺(DiC4AM)为分散相,采取先加碱共聚-共水解的方法合成了孪尾疏水缔合水溶性聚合物聚(丙烯酰胺/丙烯酸钠/N,N-二丁基丙烯酰胺)[P(AM/NaAA/DiC4AM)]。用FT IR1、H NMR对其结构、组成进行了表征和测定。用稀释外推粘度法测定了共聚物的特性粘数[η]、Huggins常数KH。用芘荧光探针法及表观粘度法研究了大分子链间的疏水缔合作用,考察了疏水单体用量对其水溶液表观粘度的影响。     

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。     

兼有离子和疏水缔合两种结构特性的聚丙烯酰胺的缔合性能

合成了新型的表面活性单体二甲基十四烷基（2-丙烯酰胺基丙基）溴化铵（DTAB）,并将该单体与丙烯酰胺在水溶液中自由基均相共聚得到了兼具离子基团和疏水基团的阳离子疏水缔合丙烯酰胺共聚物p(DTAB-co-AM)。通过表观黏度法和芘荧光探针法研究了DTAB含量、NaCl、十二烷基硫酸钠（SDS）和十六烷基三甲基氯化铵（CTAB）对共聚物缔合性能的影响。结果表明：当DTAB含量为0.3%(摩尔)时,共聚物呈盐增黏特性,在1%（质量）的盐溶液中,其临界缔合浓度由纯水中的0.15 g·dL^-1降至0.11 g·dL^-1;当DTAB含量小于0.3%（摩尔）时,仅在浓度大于5%（质量）的盐溶液中具有盐增黏特性。该共聚物与SDS作用,在疏水缔合和静电吸引两种作用下,缔合后体系的黏度最大可增加136倍,由缔合前的12 mPa·s增加到1634 mPa·s,而与CTAB作用,由于只有疏水缔合作用,缔合强度较弱黏度增加不大。     

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。     

疏水缔合水溶性聚合物P(AM/NaAA/DiAC16)水溶液的黏度行为

采取前加碱二元胶束共聚-后水解法合成了三元疏水缔合水溶性聚合物聚(丙烯酰胺/丙烯酸钠/N,N-双烯丙基十六胺)[P(AM/NaAA/DiAC16)],研究了其水溶液的黏度行为。当x(DiAC16)=0.10%~0.40%时,在30℃、1 mol/LNaCl水溶液中,P(AM/NaAA/DiAC16)的特性黏数[η]、Huggins常数KH、黏均相对分子质量Mη分别为22.59~19.62 dL/g、0.144~0.294和12.49×106~10.47×106g/mol;KH小于0.8,表明其分子内缔合作用较弱。P(AM/NaAA/DiAC16)在矿化度为19 334μg/g盐水溶液中的表观黏度随疏水单体用量的增加而增加,随温度、剪切速率的增加而降低。在NaCl、CaCl2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,P(AM/NaAA/DiAC16)出现盐增黏现象,疏水单体用量越高,盐增黏效应越显著。当ρ(SDS)=0~0.07 g/dL时,P(AM/NaAA/DiAC16)水溶液的表观黏度有明显增加,表明P(AM/NaAA/DiAC16)/SDS分子缔合作用较强。     

AM-AA-ADMOAB共聚物的合成及其水溶液的黏度性能

通过丙烯酰胺 (AM)、丙烯酸 (AA)与甲基丙烯酰氧乙基二甲基辛基溴化铵 (ADMOAB)共聚 ,合成了疏水化水溶性共聚物 (HAPAM)。考察了HAPAM的组成、质量浓度及无机盐对其水溶液黏度行为的影响。发现组成对黏度有直接影响 ,水溶液黏度随共聚物的质量浓度增加而增大并存在临界缔合质量浓度 ρ ,ρ 与其组成紧密相关。结果表明 :由于在聚合物中引入了疏水结构及两性离子结构 ,这类聚合物表现出较好的抗盐性能     

丙烯酰胺/丁基苯乙烯衍生物疏水缔合共聚物的溶液性能

采用自由基胶束聚合法合成了丙烯酰胺（AM）/丁基苯乙烯（BS）疏水缔合水溶性共聚物(PSAM).凝胶渗透色谱（GPC）测试结果显示,PSAM的重均分子量为1.6868×10⁵,环境扫描电镜（ESEM）照片显示,PSAM在水溶液中形成了疏水缔合网络结构,结果表明,PSAM的增黏能力主要依赖于疏水结构单元的分子间疏水缔合作用.PSAM溶液性能的研究结果表明,溶液质量浓度超过0.1 g·dl^-1时,共聚物具有优良的增黏、耐盐及耐温性能,在80℃时显示良好的抗老化性能;PSAM亚浓溶液为假塑性流体,具有良好的触变性,低剪切速率下在最初一段时间内呈现剪切增稠性质.     

疏水缔合两性聚丙烯酰胺的合成与性能研究

利用疏水单体苯乙烯能够提高分子链刚性,可以与丙烯酰胺进行共聚,并且苯乙烯与丙烯酰胺共聚物在水溶液中存在疏水缔合作用的特性,将苯乙烯、丙烯酰胺和3-[2-(N-甲基丙烯酰胺基)-乙基二甲基铵基]丙基磺酸盐采用反相乳液聚合的方式进行聚合反应得到一种疏水缔合的两性聚丙烯酰胺。聚合物结构经过核磁和红外验证,并对其耐盐性能进行验证,着重研究了其耐温性能,该种聚合物耐温性能有显著提高。该聚合物经100℃老化48h后剪切黏度保留率达到63%,而80℃老化48 h后剪切黏度保留率则高达87%。     

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.     

Synthesis,characterization, and solution properties of a surface‐active hydrophobically associating polymer

A nonionic surfmer (MAA‐EO₂₃C₁₂) was prepared and reacted with acrylamide, acrylic acid, and a double tailed hydrophobic monomer (BTMAM) to synthesize a surface‐active hydrophobically associating copolymer (SHAP) through photoinitiated free radical copolymerization in aqueous solution. Fourier transform infrared and ¹H‐nuclear magnetic resonance spectroscopy were used to characterize the functional monomer and the SHAP. Several performance evaluations, such as viscosification property, temperature resistance, salt tolerance, and shear resistance, were also conducted. Experiment results demonstrated that the introduced nonionic surfmer and hydrophobic monomer could endow the copolymer with excellent temperature resistance, salt tolerance, and shear resistance capability at low concentration. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46569.     

表面活性剂对疏水改性丙烯酰胺共聚物增粘性能的影响

采用自由基胶束聚合法合成丙烯酰胺/丁基苯乙烯疏水缔合水溶性共聚物(PSAM),所用的十二烷基硫酸钠(SDS)、辛基酚聚氧乙烯醚(OP-10)和十六烷基三甲基溴化铵(CTAB)能显著影响疏水单体在聚合产物中的含量,从而影响聚合物的溶液粘度,其中以SDS合成得到的产物的溶解性及增粘性能最好。另外,少量表面活性剂的加入能显著地提高聚合物亚浓溶液的粘度,在十二烷基苯磺酸钠(SDBS)、SDS和CTAB中,SDBS对聚合物亚浓溶液粘度的影响最大,其浓度为0.7 mmol/L时,0.3 g/dL PSAM溶液的表观粘度从237 mPa.s上升到981 mPa.s。     

Studies on the self‐assembly behavior of the hydrophobically associating polyacrylamide

Contrasted with partially hydrolyzed polyacrylamide (HPAM), the self‐assembly behavior and microstructure of hydrophobically associating polyacrylamide (HAPAM) in aqueous solution have been studied by means of fluorescence spectrum, transmission electron microscopy (TEM), atomic force microscope (AFM), and apparent viscosity test in this article. The fluorescent probe analysis indicates that the HAPAM molecules will form associating aggregates in pure water. The results show that HAPAM can easily self‐assemble to form an aggregate by hydrophobic driving force in dilute aqueous solution. The association of hydrophobic groups of the HAPAM causes the formation of supermolecule, so there are associating aggregates formed at very low concentration and then leads to the formation of network at a higher concentration. TEM and AFM measurements show that a distinct network structure has been formed in 1000 mg L^?1 of HAPAM solution, indicating the strong association of hydrophobic groups. These results are consistent with the viscosity measurement and reveal that the excellent viscosification of HAPAM is due to the association of hydrophobic groups in the aqueous solution. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

双尾型丙烯酰胺类疏水缔合共聚物的合成与表征

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:丙烯酸加量和表面活性剂含量的变化会影响聚合物的临界缔合行为;盐的引入能够显著降低表面活性剂的用量,提高聚合物的增黏效果;疏水单体含量较低时[0.35%～0.45%(mol)],聚合物可以表现出明显的增黏效果。当聚合物浓度为1 g·L^-1时,聚合物的黏度可以达到141.5 mPa·s,其临界缔合浓度(CAC)为0.75 g·L^-1左右。聚合物在120 g·L^-1的NaCl溶液和120 g·L^-1 NaCl、0.4 g·L^-1 CaCl₂溶液中,80℃下老化90 d,黏度分别为47.6 mPa·s和45.9 mPa·s。采用红外光谱、扫描电镜两种手段,表征了聚合物的结构。     

三次采油用聚合物驱油剂PL-2的合成与溶液性能研究

采用胶束聚合的方法合成了三次采油用聚合物PL-2,室内研究了表面活性剂的浓度、疏水单体、阴离子单体含量以及在盐水中聚合物溶液表观粘度的影响,并进一步评价了合成聚合物的抗剪切性与热稳定性。实验结果表明:疏水单体与阴离子单体含量分别在0.6%与10%时,该聚合物驱油剂PL-2具有很好的增粘效果,且抗剪切及热稳定性能优良,其性能可以满足高温、高矿化度油藏聚合物驱油的要求。     

Synthesis and aqueous solution properties of hydrophobically modified graft copolymer of sodium carboxymethylcellulose with acrylamide and dimethyloctyl(2‐methacryloxyethyl)ammonium bromide

The hydrophobically modified water‐soluble graft copolymer of sodium carboxymethylcellulose with acrylamide and dimethyloctyl(2‐methacryloxyethyl)ammonium bromide has been synthesized using potassium persulfate and dimethylaminoethyl methacrylate as initiators in aqueous solution. The structure and composition of the graft copolymer were characterized by infrared spectrum and elementary analysis. Molecular weight was determined by gel permeation chromatography. The solubility and viscosity of the graft copolymers in aqueous solution were investigated, as a function of copolymer concentration, added salt, temperature, shear rate, and surfactant. In addition, the intermolecular hydrophobic association in aqueous solutions in the presence of added salt and surfactant was demonstrated through the retention time from gel permeation chromatography measurement. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 537–542, 2000