阴离子瓜尔胶的制备及其稀溶液性质

在碱催化剂作用下,用改性剂2-氨基乙磺酸钠-4,6-二氯-1,3,5-均三嗪与瓜尔胶反应制得新型阴离子瓜尔胶(AGG),采用IR对AGG进行了表征。借助乌氏黏度计研究了AGG的稀溶液性质,考察了温度和外加盐浓度对AGG的影响。结果发现,随着温度的升高,其特性粘度先增大后减小;而其特性粘度则随着NaCl溶液浓度的增加先减小后增大。     

磺酰卤基羟丙基瓜尔胶的合成及其性能北大核心

首先合成中间体3-氯-2-羟基丙磺酸钠,然后以3-氯-2-羟基丙磺酸钠、瓜尔胶为原料,氢氧化钠为催化剂,采用溶剂热法合成了磺酰卤基羟丙基瓜尔胶,表征了磺酰卤基羟丙基瓜尔胶的结构,并研究了其交联性能。结果表明:瓜尔胶分子中引入了磺酰卤基和羟丙基,成功合成了磺酰卤基羟丙基瓜尔胶;磺酰卤基羟丙基瓜尔胶具有良好的交联性能,是优良的压裂液稠化剂。     

磺酰卤基羟丙基瓜尔胶的合成及其性能

首先合成中间体3-氯-2-羟基丙磺酸钠,然后以3-氯-2-羟基丙磺酸钠、瓜尔胶为原料,氢氧化钠为催化剂,采用溶剂热法合成了磺酰卤基羟丙基瓜尔胶,表征了磺酰卤基羟丙基瓜尔胶的结构,并研究了其交联性能。结果表明:瓜尔胶分子中引入了磺酰卤基和羟丙基,成功合成了磺酰卤基羟丙基瓜尔胶;磺酰卤基羟丙基瓜尔胶具有良好的交联性能,是优良的压裂液稠化剂。     

瓜尔胶的改性及其透光性能研究

瓜尔豆片为原料,经羟丙基提纯后阳离子改性,得到透明性较好的阳离子瓜尔胶（CGG）。经分析碱法水解除蛋白质最优工艺为：豆片25g,NaOH5g,98℃下反应3h：蛋白质去除率为98．24％,透光率达77％。羟丙基化较优工艺为：环氧丙烷8mL。60℃反应4h;羟丙基取代度为0．2650,透光率为89％e阳离子化最优工艺为：醚化剂10mL,60℃反应3～5h,取代度（DS）为0．1701,透光率达97％。用IR对产蹦结构进行了表征,用TG和DSC对瓜尔胶、羟丙基瓜尔胶和阳离子瓜尔胶的对比研究表明,接枝的阳离子基团对瓜尔胶的相态稳定温度有影响,阳离予瓜尔胶的水分含量和结合水含量有所降低,利于储存。此产品用于对透光率要求较高的领域。     

改性羟丙基瓜尔胶/表面活性剂复合压裂液

以溴代十四烷对羟丙基瓜尔胶进行了疏水改性，对改性产物进行了红外和热重分析。用质量分数0.15%疏水改性羟丙基瓜尔胶和质量分数0.8%阳离子双子表面活性剂1,3-N-双（3-十二烷基丙酰胺）-1,1,3,3-N-四甲基异丙醇-1,3-二溴化铵制备了复合压裂液，并对复合压裂液的耐温耐剪切性、流变性、动态携砂性、破胶液界面性质、储层伤害性进行了系统评价。结果表明，羟丙基瓜尔胶成功接入了疏水碳链，且热稳定性良好；所制备的复合压裂液在90℃下黏度高于109 mPa·s；该体系表现为典型的黏弹性流体，动态携砂性良好；破胶液油/水界面张力为0.9 mN/m，且可显著增强储层岩石亲水性；储层基质油相渗透率损害率和裂缝导流能力损害率分别仅为9.1%和5.3%。     

阳离子瓜尔胶粘度对头发梳理性的影响

以瓜尔胶为原料,3-氯-2-羟丙基三甲基氯化铵为醚化剂,氢氧化钠为催化剂,乙醇为溶剂,制备了阳离子瓜尔胶。利用头发梳理仪测定了洗发水中添加阳离子瓜尔胶前后,头发之间的摩擦力变化,考察了阳离子瓜尔胶对头发干、湿梳理性的影响,得出阳离子瓜尔胶能明显改善头发的梳理性:3300mPa.S以上粘度的阳离子瓜尔胶显示效果较佳。     

瓜尔胶基高吸水性树脂的制备、溶胀行为与保水性能

以天然瓜尔胶（GG）和丙烯酸（AA）为原料,过硫酸铵（APS）为引发剂,N,N′-亚甲基双丙烯酰胺（MBA）为交联剂,采用水溶液聚合法制备了瓜尔胶接枝聚丙烯酸（GG-g-PAA）高吸水性树脂。考察了MBA浓度对树脂溶胀动力学和溶胀能力的影响,研究了树脂在不同亲水有机溶剂/水混合溶液、不同阳离子盐（NaCl、CaCl₂和FeCl₃）和阴离子盐（KNO₃、K₂SO₄和K₃PO₄）溶液中在各浓度和离子强度下的溶胀行为,测定了高吸水性树脂在室温和高温下的保水性能。结果表明,该树脂对亲水有机溶剂较为敏感,吸水倍率随着亲水有机溶剂浓度的增加迅速减小;在各种盐溶液中的吸水倍率随着离子强度的增加而下降。     

瓜尔胶的化学改性

简要介绍了瓜尔胶的结构及其化学改性的原理和方法;综述了国内外瓜尔胶化学改性的研究工作;详细介绍了非离子瓜尔胶、阳离子瓜尔胶、阴离子瓜尔胶、羟烷基阴离子瓜尔胶和羟烷基阳离子瓜尔胶以及两性瓜尔胶的合成方法。瓜尔胶通过改性改善了水溶性、大大降低了水不溶物的含量、提高了电解质的兼容性、增加了黏度的稳定性、从而扩大了瓜尔胶的应用领域,使得改性瓜尔胶广泛应用于化妆品、个人护理品、造纸、油田和增稠剂等众多领域。     

微波辅助阳离子瓜尔胶的合成研究

以瓜尔胶为原料,3-氯-2-羟丙基三甲基氯化铵为醚化剂,氢氧化钠为催化剂,异丙醇作为溶剂,利用微波辅助合成了阳离子瓜尔胶。结果表明,在瓜尔胶醚化过程中使用微波辅助,反应时间是传统阳离子瓜尔胶合成方法的1/6,提高了反应效率。最佳反应条件为:溶剂选用85%异丙醇,微波功率300 W,微波辐射时间为30 min,反应温度40℃,醚化剂与瓜尔胶的物质的量比为0.25,碱与瓜尔胶的物质的量比为0.20。产物水溶性很好,可与表面活性剂复配。     

一种合成季铵盐阳离子瓜尔胶的新方法

以瓜尔胶胚乳片为原料,3-氯-2-羟丙基三甲基氯化铵为阳离子醚化剂,在水媒介中合成阳离子瓜尔胶。利用FTIR光谱对阳离子瓜尔胶进行结构表征。通过正交试验研究碱的用量、阳离子醚化剂用量、反应温度、反应时间对产物的取代度的影响。结果表明,在胚乳片为100 g,NaOH为12 g,3-氯-2-羟丙基三甲基氯化铵为50 g,45~50℃反应60 min条件下,可以得到取代度0.08的季铵盐瓜尔胶,其中碱量和阳离子醚化剂用量对产物取代度影响较大。     

Carboxylic modification of welan gum

Welan gum has disadvantages such as poor solubility, low viscosity, and poor crosslinking property, when it is applied in petroleum industry, comparing to guar gum. Two methods for the carboxylic modification of welan gum were developed, carboxyethyl modification and citric acid modification, to improve the solubility in water, viscosity, and crosslinking ability of welan gum in the borax crosslinking system. The solubility time of carboxyethyl modified and citric acid modified welan gum were shortened to 30 and 90 min, respectively. The highest viscosity of citric acid modified product was 49.4 mPa s, the viscosity after crosslinking was raised at least 1.2 times to the highest four times than that before crosslinking. The results indicated three factors affecting the properties of modified products: (1) how many function groups in the modifying agent; (2) the way to connect the function group; and (3) the whole structure of the modifying agent. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48301.     

改性瓜胶压裂液的合成与性能评价

针对目前水力压裂液耐温性不足的缺点,基于最常用瓜胶为原材料,对瓜胶经行醚化改性,先用Na OH碱化,再进行卤代烃取代,筛选出最佳合成条件。以改性瓜胶为稠化剂,优选出交联剂TMP-8A作为改性瓜胶的稠化剂,流变测试表明该体系在170 s~(-1)剪切和140℃的条件下测试2h后,能满足压裂液要求。体系中粘土稳定剂DF-21的防膨率达到了90.34%,胶囊破胶剂GC07在114 min完成破胶,助排剂DV-04返排液表面张力达到18.5 m N/m。表明该体系具有很好配伍性,满足现场施工要求。     

Cotton linter nano-fibers as the potential reinforcing agent for guar gum

Cotton linter nano-fibers (CLNFs) were prepared from cotton linters by a refining process. The prepared CLNFs were characterized for morphology, crystallinity and degree of polymerization. CLNF was used as a reinforcing agent in guar gum to improve its performance properties. Guar gum/CLNF nanocomposite films were prepared by a solution-casting process. CLNF was added in concentrations of 0.1, 0.25, 0.5 and 1.0 % (w/w) in guar gum. The prepared guar gum/CLNF nano-composite films were characterized for mechanical, thermal, rheological, crystallinity, water vapor transmission rate (WVTR) and light transparency properties. The enthalpy of melting and melting temperature of guar gum increased with increased concentration of CLNF; but up to 0.25 % (w/w) concentration, above which they started decreasing. Tensile strength and Young’s modulus of guar gum increased by 32 and 35 %, respectively, by 0.25 % (w/w) addition of CLNF; however, it decreased on further increase in the concentration of CLNF. The percentage elongation at break and WVTR decreased by 58 and 57 % for 0.25 % (w/w) CLNF-added guar gum. The observed improvements in the properties were due to better interaction between CLNF and guar gum. CLNF was found to have uniformly dispersed in guar gum on addition up to 0.25 % concentration; however, it started forming aggregates at higher concentration, as evident from scanning electron microscopy. Viscosity increased, whereas transparency decreased with increased concentration of CLNF in guar gum.     

有机锆对羧甲基羟丙基瓜胶的交联性能研究

以氧氯化锆和柠檬酸等为原料,合成了适用于羧甲基羟丙基瓜胶在酸性条件下交联的有机锆交联剂,考察了pH值、温度、羧甲基羟丙基瓜胶和交联剂加量等对体系成胶时间的影响,评价了形成冻胶的抗温抗剪切性能、滤失性能和破胶性能.实验发现,在pH值为3.0时,羧甲基羟丙基瓜胶/有机锆体系具有可控的延缓交联特性,质量分数为0.5%和0.6...     

Preparation and evaluation of a cosmetic adhesive containing guar gum

Guar gum is an effective agent for use as a natural adhesive ingredient that can be used to replace the hazardous ingredients of spirit gum. This study describes the possibility of using guar gum as a renewable substituent for cosmetic adhesive. An adhesive base and cosmetic adhesive containing guar gum were prepared by a two-step process. The samples were tested for safety (cell toxicity test and patch test), stability (centrifugation, cycling and viscosity), and effectiveness (tensile strength). The results from the MTT assay show that the growth activity of human fibroblast skin cells was over 89% in all concentrations of cosmetic adhesive containing guar gum. In addition, no special skin reactions were reported in the patch test prepared adhesive containing guar gum. Moreover, the stability test demonstrated proper stability of all adhesive samples: the composition stability, heat stability, and viscosity of the adhesive samples maintained stable conditions. The efficacy test confirmed the superiority of the guar gum adhesive samples over spirit gum concerning the tensile strength. This study demonstrated that guar gum may be a viable replacement for synthetic rosins and also as a substituent in cosmetic.     

Pentaerythritol encapsulated with boric acid: An efficient composite crosslinker for guar gum fracturing fluid

Commonly used crosslinker agents often have a low crosslinking efficiency with guar gum, the major component of fracturing fluid for crude oil recovery, and it often required a high loading of guar gum for achieving desired recovery from low-permeability reservoir. Nevertheless, a high-loading of guar gum might result in excessive residue and reduce the conductivity of the reservoir. Therefore, boric acid, a commonly used crosslinking agent, was introduced onto the surface of pentaerythritol to afford a composite crosslinking agent denoted as PB. The as-prepared PB crosslinker was characterized by Fourier-transform infrared spectrometry. The guar gum fracturing gel crosslinked with the PB had fantastic viscoelasticity and thermal stability and could reduce the guar gum loading by 16.7%, with boric acid as a control. Besides, the gel-broken liquid had good compatibility with the simulated water and caused reduced damage to rock core, showing potential for hydraulic fracturing of low-permeability reservoirs. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48528.     

耐高温胍胶压裂液及其对储层的伤害机理研究进展

随着油气资源的勘探开发不断向深层超深层储层发展,常规胍胶压裂液不能满足高温超高温储层压裂施工需求。国内外学者致力于从胍胶耐温改性与新型耐高温交联剂合成两个方向提升胍胶压裂液的耐温性能,同时研究了胍胶压裂液对储层的伤害机理,取得了较大进展。本文回顾了近年来国内外耐高温胍胶压裂液的发展动态,阐述了关于耐高温改性胍胶和耐高温交联剂合成的研究现状,从胍胶压裂液对储层的伤害类型和伤害机理角度进行了总结,重点分析了胍胶压裂液对高温储层伤害机理的研究进展。最后指出,应该继续通过化学改性进一步提高胍胶自身的耐温性能,同时加强对破胶剂和纳米交联剂的研究,并提出高效低伤害的纳米交联压裂液是耐高温胍胶压裂液未来可能的发展方向。