水性多彩涂料的研发及应用

采用天然高分子瓜尔胶为凝胶物质,制备了水性多彩涂料.通过实验发现,高黏度瓜尔胶形成的有色凝胶粒子比低黏度瓜尔胶形成的有色凝胶粒子稳定性好;玻璃化转变温度低的树脂乳液有利于本体系凝胶粒子对色浆的包裹.通过对比,筛选出了3种牌号瓜尔胶和乳液,制得具有良好装饰效果的水性多彩涂料.     

水性涂料天然流变改性剂瓜尔胶的应用研究

对天然流变改性剂瓜尔胶在水性涂料中的应用性能进行了研究,结果表明:瓜尔胶作为水性涂料的流变助剂产品性能均符合国家标准,因此,瓜尔胶可代替传统的羟乙基维素(HEC),而且具有明显的价格优势,生产成本低.     

瓜尔胶改性水性涂料的研究

采用比较法研究瓜尔胶对水性涂料的改性性能,结果表明所制得的瓜尔胶改性水性涂料符合国家标准,由此可知瓜尔胶可完全替代羟乙基纤维素(HEC),并可大幅度降低乳胶漆制造成本。     

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。     

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。     

668乳胶液

乳胶液系各种建筑涂料的关键原料。采用六种成份经有机合成的“668乳胶液”,为提高各种建筑涂料质量,降低各种建筑涂料成本开辟了途径。 世界涂料产量增长率为1％,我国则超过10％,涂料中建筑涂料占的比重最大。为乳胶液的开发提供了广阔的前景。经测试,以668乳液生产的内墙涂料,外墙涂料,防水涂料及木工用胶等的各种性能,均达到国内同类产品最高水平,并可与聚氨酯媲美,其价格则低于氯丁胶乳30％。产品市场竞争力强。     

高性能霉乳胶涂料防霉时效性测试方法初探

介绍了防霉乳胶涂料防霉时效性的意义、测试方法.给出了防霉乳胶涂料与国外防霉乳胶涂料的对比检测结果.     

水包水多彩涂料性能影响因素探讨

简述了水包水多彩涂料的发展概况,指出了目前存在的问题。重点阐述了水包水多彩涂料稳定性影响因素,讨论了乳胶类型与保护胶配伍性、水性色浆及助剂对水包水多彩涂料性能的影响。     

我国外墙乳胶涂料测试结果和使用性能之间的相关性

分析了我国外墙乳胶涂料测试结果和使用性能之间的相关性,在与美国、欧盟和日本外墙乳胶涂料质量评定进行对比的基础上,对我国外墙乳胶涂料质量评定提出一些建议.     

浙江丰利推出瓜尔胶粉碎机

<正>近段时间,浙江丰利粉碎设备有限公司推出的瓜尔胶粉碎机迎来了一批又一批订单客商,形成了生产热潮。究其原因,是一种叫瓜尔胶的粉体受到了市场追棒,带动了加工设备的热销。瓜尔胶是由瓜尔豆籽经磨碎、筛分、吹风除皮和胚芽、胚乳处理等工序加工制成的自由流动粉末。瓜尔胶     

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.     

Dietary Guar Gum Reduces Lymph Flow and Diminishes Lipid Transport in Thoracic Duct-Cannulated Rats

Guar gum has a well-recognized hypolipidemic effect. This effect is thought to be due to the physicochemical properties of guar gum, which may cause changes in adsorption of lipids or the viscosity of the intestinal contents. Guar gum is a non-specific absorption inhibitor of any type of lipid-soluble compound. Permanent lymph duct cannulation was performed on rats to investigate the effects of dietary guar gum on lymph flow and lipid transport. Rats fed a 5% guar gum diet were compared with those fed a 5% cellulose diet, and lymph was collected after feeding. The water-holding capacity (WHC), settling volume in water (SV), and viscosity of guar gum were compared with those of cellulose. Rats fed with the guar gum diet had significantly lower lymph flow and lymphatic lipid transport than did rats fed with the cellulose diet. The WHC, SV, and viscosity of guar gum were significantly higher than those of cellulose. We propose that dietary guar gum reduces lymph flow and thereby diminishes lipid transport by means of its physicochemical properties related to water behavior in the intestine.     

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。     

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。     

Synthesis of guar‐gum‐stabilized nanosized silver clusters with γ radiation

Gamma ray induced synthesis of Ag clusters in the aqueous medium has been carried out using natural polysaccharide guar gum as a stabilizer. The results showed that guar gum is very effective in binding the Ag clusters and restricts their size in the nano region. The surface plasmon resonance band in the wavelength range of 410–425 nm of visible region has confirmed the formation of Ag clusters. The size of the clusters is governed by the concentration of both, i.e. precursor Ag⁺ and guar gum. The clusters were characterized by TEM and XRD, which shows that the size of clusters is in the range of 10–30 nm. The results have shown that silver clusters stabilized by guar gum are stable in acid media and alkaline media is not a desired media for the synthesis. From thermogravimetric analysis it has been demonstrated that incorporation of nano sized Ag clusters within guar gum improves the thermal properties of irradiated guar gum. To the best of our knowledge, the use of guar gum as a stabilizer in the gamma ray induced synthesis of Ag nano clusters is being reported first time in the literature. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

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.     

Enzymatic improvement of guar‐based thickener for better‐quality silk screen printing

Guar galactomannan (referred to as guar gum) is a versatile polysaccharide, obtained from the seeds of the shrub Cyamopsis tetragonolobus, which finds several applications in either its native or chemically modified form. For textile printing, guar gum can also be partially depolymerised in order to promote dye penetration, improve swelling in water and achieve the desired rheological properties. Guar gum is obtained from guar seeds by a thermo‐mechanical process that leaves ca. 3% of largely insoluble proteins in the gum, originating from the endosperms aleurone layer. When printing silk fabrics with acid or premetallised dyes, guar endogenous insoluble proteins bind tightly to anionic dyes, causing deposition of coloured aggregates on the fabric. This causes imperfections on the printed fabric in the form of tiny, but visible, ‘dots’, which lowers the quality of the final articles. In order to eliminate ‘dotting’, a novel printing thickener composed of depolymerised guar gum mixed with a bioengineered subtilisin protease has been developed. Upon solubilisation of the gum, and during preparation of the printing paste mixture, the protease hydrolyses guar gum insoluble proteins, generating soluble peptides that are washed off by the post‐printing treatments of the fabric. This enzymatic application prevents ‘dotting’ and significantly improves the quality of the silk print, without any measurable tensile strength loss of the fabric.