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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。 相似文献
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通过对阳离子瓜尔胶的制备方法、影响因素及其在洗发香波中应用的研究,得到有机溶剂法制备阳离子瓜尔胶的最佳工艺条件如下:以异丙醇作溶剂,瓜尔胶用量10g,CTA用量2.5g,氢氧化钠用量0.8g,在80℃下,持续反应9h,所得阳离子瓜尔胶的取代度为0.075,反应效率为73%。1.0%的阳离子瓜尔胶可以使洗发香波的粘度由1650mPa·s增至8150mPa·s,洗发后使毛发显著变得柔软光滑。 相似文献
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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。 相似文献
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以瓜尔胶(GG)为原料、3-氯-2-羟丙基二甲铵基乙酸盐(CCDH)为两性醚化剂,在碱催化剂作用下半干法合成了不同取代度的ZGG,并通过IR对CCDH和ZGG进行了表征。同时考察了体系中碱用量、反应温度、反应时间对产品取代度的影响。结果表明,当瓜尔胶用量为8 g,CCDH为4 g,NaOH为0.06 g,温度为65℃,反应时间为5 h,取代度为0.544。 相似文献
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There has been a growing interest in the modification of guar gum to improve its properties and enlarge its application. The aim of this study was to prepare partially hydrolyzed cross-linked guar gum with a composite modification method, based on guar gum, hydrochloric acid, epichlorohydrin and solvent. To obtain a product with suitable properties for other fields, the effects of various factors such as reaction time, reaction temperature, pH, the amount of ethanol and cross-linking agent on the cross-linking degree of partially hydrolyzed cross-linked guar gum were studied. The stability of the hot paste viscosity, cold paste viscosity, acid resistance, alkali resistance, retrogradation, freeze–thaw stability and swelling power were determined. The product was characterized by differential scanning calorimetry. The sedimentation volume method was selected to determine the cross-linking degree of the product. The best conditions for preparing partially hydrolyzed cross-linked guar gum were: reaction temperature 50 °C, reaction time 4 h, the amount of ethanol 58 %, pH 10.5. After guar gum was modified by acid, or cross-linked by epichlorohydrin, its freeze–thaw stability and expansion capability decreased, but its acid resistance, alkali resistance, cold paste stability and hot paste viscosity stability were improved. 相似文献
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Jeong Hee Kim Hye Jo Min Kun Park Jin Kim 《Korean Journal of Chemical Engineering》2017,34(8):2236-2240
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. 相似文献
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The synthesis of two polysaccharide‐based graft copolymers with acrylamide, guar gum grafted polyacrylamide (GG‐g‐PAM) and hydroxypropyl guar gum grafted polyacrylamide (HPG‐g‐PAM) is described. The graft copolymers have been characterized by viscometry, infrared spectroscopy and thermal analysis. The flocculation characteristics of the graft copolymers have been studied in kaolin, iron ore, and silica suspensions. For the base polysaccharides guar gum (GG) and hydroxypropyl guar gum (HPG), it is observed that GG exhibits better performance than HPG in all three suspensions. For the graft copolymers, HPG‐g‐PAM shows better performance than GG‐g‐PAM. The flocculation characteristics of the best performing graft copolymer (HPG‐g‐PAM) are compared with various commercially available flocculants in the three suspensions mentioned above. © 2001 Society of Chemical Industry 相似文献
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A series of novel superabsorbent nanocomposites were prepared by the solution radical polymerization of natural guar gum (GG), partially neutralized acrylic acid [sodium acrylate (NaA)], and cation‐exchanged vermiculite (Mn+‐VMT) with ammonium persulfate as the initiator in the presence of the crosslinking agent N,N′‐methylene‐bis‐acrylamide. Fourier transform infrared analysis revealed that NaA was grafted onto the GG chains and that Mn+‐VMT participated in the polymerization. X‐ray diffraction results showed that the occurrence of the cation‐exchange process changed the interlayer gap of vermiculite (VMT) and that Mn+‐VMT was exfoliated during polymerization to form a nanocomposite. The exfoliated VMT led to better dispersion in the GG‐g‐poly(sodium acrylate) matrix, as shown by scanning electron microscopy and transmission electron microscopy analysis. Mn+‐VMT improved the water absorption of the nanocomposite more remarkably than raw VMT, and Al3+‐VMT enhanced the water absorption to the highest degree. The nanocomposite exhibited intriguing overshooting swelling characteristics in a multivalent saline solution and acidic pH solution and showed switching pH‐responsive behaviors in buffer solutions between pH 2 and pH 7.2. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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两性离子型瓜尔胶的制备及稀溶液性质 总被引:1,自引:0,他引:1
以瓜尔胶(GG)为原料,2,3-环氧丙基二甲铵基乙酸盐(ECDH)为两性醚化剂,在碱催化剂作用下干法合成了新型两性离子型瓜尔胶(ZGG)。采用酸碱滴定法测定了ZGG的等电点,并借助乌氏黏度计研究了等电点范围内ZGG的稀溶液性质,考察了外加盐浓度和不同外加盐对ZGG的影响。结果发现,随着氯化钠溶液浓度的增大,其特性黏度增大,表现出明显的反聚电解质溶液行为,二价金属离子对ZGG的影响大于一价金属离子对其的影响,即CaCl2>MgCl2>NaCl。 相似文献
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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。 相似文献
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Guar gum is a galactomannan commonly used as a viscosity modifier in the food, pharmaceutical, and cosmetics industry. The aim of this study was to synthesize acryloyloxy guar gum via a Schotten‐Bauman reaction in aqueous media. The reaction products were characterized using FTIR, C13‐NMR, wide angle X‐ray diffraction techniques to ascertain the effect of acrylation on the structure of guar gum. The acrylation of guar gum was found to be limited to the primary hydroxyl groups on the guar gum molecule. The maximum degree of substitution (DS) was found to be 0.56, which was observed after 3 h of reaction. Since the reaction was carried out in an aqueous medium after 3 h of reaction the DS of the derivatised guar gum was found to decrease, because of hydrolysis of the formed ester linkages. The ester content and intrinsic viscosity of the derivatised guar gums were also evaluated. Thermal analysis showed that a higher DS resulted in products with lower thermal stability and there was no evidence of reaction via the acrylate groups on heating. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
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Vermiculite (VMT) was modified with cetyl trimethylammonium bromide (CTAB). Superabsorbent nanocomposites were prepared by solution polymerization of natural guar gum (GG), partially neutralized acrylic acid (NaA) and organo-vermiculite (CTA+-VMT), ammonium persulfate (APS) as initiator and N,N′-methylene-bis-acrylamide (MBA) as crosslinking agent. FTIR spectra confirmed that NaA had been grafted onto GG and the OH groups of CTA+-VMT participated in the polymerization reaction. The intercalated-VMT was exfoliated during polymerization and uniformly dispersed in the GG-g-PNaA matrix. Swelling tests show that CTA+-VMT improved swelling and swelling rate more remarkably than VMT, and the nanocomposite exhibited distinct kinetic swelling behavior in NaCl and CaCl2 solution. Organo-VMT improved the gel strength of the nanocomposite compared to VMT, and the maximum storage modulus of the nanocomposite reached 658 Pa (γ = 0.5%, ω = 100 rad/s). 相似文献