κ-卡拉胶和魔芋胶复合凝胶的制备及吸附亚甲基蓝综合实验

以κ-卡拉胶和魔芋胶为原料,通过温度变化制备不同比例的复合水凝胶,吸附水溶液中亚甲基蓝。并将其转化为切实可行的大学生实验项目。实验采用红外光谱法和电子扫描显微镜研究凝胶的组成和微观形貌。通过对水凝胶吸附亚甲基蓝的动力学特征研究,得到不同水凝胶的吸附速率等参数。溶液中亚甲基蓝与κ-卡拉胶相互作用形成堆叠结构,通过检测560 nm处吸收光谱峰的强弱分析堆叠结构的含量,进而表征不同组成凝胶在溶液中的稳定性。     

魔芋胶的交联化学改性研究

采用三氯氧磷、氯乙酸醚化和卡拉胶复配三种方法对魔芋葡甘聚糖(KGM)进行改性,采用AR500动态流变仪测定了魔芋胶的剪切弹性模量和粘性模量随温度和角频率的变化,并与改性后的样品作了比较。结果显示,不同的改性方法可以有效调控魔芋胶的流变性,使之适应更广泛的技术要求,拓展应用范围。     

魔芋微粉及其复配胶在化妆品领域中的开发应用

提出一种生产粒度为150目～200目脱杂魔芋微粉的方法以及用该粉与卡拉胶、黄原胶经复配后的产物作为增稠剂和凝胶成膜剂 ,可作为一类价格低廉、效果理想的成型剂广泛用于化妆品领域 ,具有可观的应用前景。     

刺云实胶/魔芋葡甘聚糖复合凝胶流变性能研究

为了获得性能更优良的食品凝胶体系,本研究将刺云实胶(TG)与魔芋葡甘聚糖(KGM)按一定比例复配制得复合凝胶,通过旋转流变仪研究其流变性能,用统计力学和动力学相结合的方法,对KGM与TG分子链的链间作用进行深入研究。实验结果表明,TG/KGM凝胶在高温下为假塑性流体,二者具有良好的相容性,复配溶胶体系的剪切应力和黏度均随着KGM组分比例的增加而增加,抗剪切能力有所增强。在选定的频率范围0.1~100 rad/s内,TG/KGM的损耗模量G”低于其储能模量G’,KGM的添加使得模量上升。而在85~25℃的降温过程中,随着KGM的增加,复配体系中G’和G”模量下降,溶胶向凝胶的转化温度点发生右移,以上表明相比于单一多糖,适量的KGM与TG复配,可以大大提高凝胶耐热性,形成稳定性高的凝胶。分析得出,在不同质量比的TG/KGM凝胶体系中,当m(TG):m(KGM)=0.9:0.6（即TK6）时,可得到综合性能优异、胶凝能力强、稳定性高且黏度适中的凝胶体系。研究表明,制备的TG/KGM凝胶有望成为一种新型食品凝胶,可以为TG和KGM的合理应用提供理论指导。     

锌基复合气凝胶的制备与表征

以氯化锌为原料,柠檬酸为模板剂制备了锌基复合气凝胶,通过场发射扫描电镜(FESEM)、高分辨透射电镜(HRTEM)、X射线衍射(XRD)、N2吸/脱附以及红外谱图(FTIR)对气凝胶的结构进行了表征,结果表明:锌基复合气凝胶是由大量纳米级的球状颗粒堆积而成,具有典型的三维网络结构,其骨架是由大量非晶态的颗粒组成的;气凝胶具有较高的比表面积为177 m2/g,其孔径分布主要集中在10~60 nm,为介孔材料。     

魔芋葡甘聚糖复合凝胶的制备及其溶胀性能研究

通过在水中复配魔芋葡甘聚糖(KGM)、黄原胶(XG)和β-环糊精(β-CD),制备了KGM/XG/β-CD复合水凝胶。探讨了β-CD含量对凝胶平衡溶胀度的影响,并探讨了介质pH和温度对凝胶溶胀度的影响。结果表明,当m(KGM):m(XG):m(β-CD)=1:1:1时,复合凝胶的平衡溶胀度最大;复合凝胶的溶胀度在溶胀初期增加很快,随着溶胀时间的延长,溶胀度增加变慢,约7 h内基本达到平衡;随着介质pH的增大或体系温度从25℃增加至37℃,KGM/XG/β-CD复合凝胶的溶胀度随之增大。     

pH敏感魔芋葡甘聚糖复合凝胶的制备及其缓释性能研究

以魔芋葡甘聚糖(KGM)-黄原胶(XG)共混多糖为载体,进一步复配β-环糊精(β-CD)得到KGM/XG/β-CD复合干凝胶;以香兰素为模型香精,制备了装载香精的KGM/XG/β-CD复合凝胶,研究了装载香兰素的复合凝胶的释放行为,并与KGM/XG复合凝胶的释放行为做了比较。结果表明:在p H分别为5,7和9的缓冲液中,KGM/XG/β-CD复合凝胶中的香兰素12 h后累积释放率分别为29.5%,47.7%和60.6%,较KGM/XG复合凝胶中的香兰素在12 h后累积释放率(分别为45.0%,69.3和82.3%)低,表明具有空腔结构的β-CD对香兰素的释放起到了较好的缓释作用。     

魔芋葡甘聚糖与结冷胶协同相互作用及凝胶化研究

魔芋葡甘聚糖与结冷胶按一定比例共混得到凝胶,测定凝胶强度,并用红外光谱仪对多糖分子间的相互作用机理进行分析.当总糖浓度为1.0％（wt）,魔芋胶与结冷胶共混比例为40/60,制备温度为80℃,体系盐离子（Ca2＋）浓度为6.0 mmol/L时可得到协同相互作用最大值,这是多糖分子间相互作用,发生了聚合交联,产生了协同增效作用.     

琼脂和卡拉胶凝胶性能研究

利用质构仪测量琼脂和卡拉胶凝胶特性,重点研究了Mg2+、浓度和pH值对琼脂和卡拉胶凝胶强度的影响。结果表明,琼脂凝胶强度随着Mg2+浓度的增加有小趋势的增加,因此可在琼脂中添加Mg2+,而Mg2+不能使卡拉胶凝胶,浓度是影响凝胶强度的主要因素,凝胶强度随着浓度的增加而增加,随着pH先增后减。     

CuO（CoO，MnO）／SiO2纳米复合气凝胶的溶胶-凝胶法制备、成胶机理及表征

采用正硅酸乙酯(tetraethyl orthosilicate.TEOS)和Cu、Co、Mn的醋酸盐溶液.通过溶胶-凝胶法、常压干燥制备了过渡金属氧化物含量高达75wt%的CuO(coO,MnO)/SiO2纳米复合气凝胶.采用透射电镜(TEM),傅里叶变换红外分析(FTIR)、电子散射能谱分析(EDS)和化学分析等对其微观结构、组成及成胶机理进行了探讨.结果表明:CuO(coO,MnO)/SiO2纳米复合气凝胶的颗粒约在5～10nm,并具有SiO2气凝胶的纳米孔隙三维网络结构和高比表面积;根据过渡金属醋酸盐与TEOS比例的不同,Cu、Co和Mn能够与氧在网络结构中形成不同程度的-0-M-o-桥键连接;通过气凝胶的多孔网络分隔作用,可使更多金属氧化物CuO、CoO和Mno的纳米粒子均匀分散于CuO(coO,MnO)/SiO2复合气凝胶或SiO,气凝胶骨架中.这种结构既有利于提高催化剂负载量,又可充分利用CuO,CoO和MnO的助催化作用.     

Reacetylated chitosan/cashew gum gel: Preliminary study for potential utilization as drug release matrix

The aim of this work was to characterize and investigate the potential of chitosan/cashew gum (CH/CG) gel for the controlled release of pilocarpine hydrochloride. Gels were prepared by reacetylation of CH with acetic anhydride, characterized by infrared spectroscopy, thermal analysis, and X‐ray diffraction. Swellings in water and in phosphate buffers were also investigated. The release of pilocarpine for CH and CH/CG gels was shown to be similar in the first 100 min, where about 60% of the pilocarpine was released. After this time, addition of CG to the gels decreases pilocarpine release rate in the medium. CH gel release was found to be dependent on pH values, a non‐Fickian mechanism was observed for the release at pH 2 and 7.4, while at pH 9.8, a Fickian (diffusion) mechanism took place. On the other hand the release of pilocarpine in CH/CG matrix occurred by Fickian mechanism, independent of the pH value. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 326–334, 2006     

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。     

两性离子型瓜尔胶的制备及稀溶液性质

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。     

Synergistic interaction of konjac glucomannan and gellan gum investigated by rheology and texture analysis

The rheological kinetics of konjac glucomannan and gellan gum mixed sols were studied using rotational concentric cylinder viscometer. The effects of polymers weight ratio, shear rate, and temperature were systematically investigated. The curves showed a Newtonian plateau followed by strong shear thinning that can be described by a power law dependence on the shear rate. The dynamic viscoelastic character was evaluated by measurements of small-deformation oscillatory. After adding some cations, the mixed sols turned into mixed gels. The contribution of Na⁺, K⁺, Ca²⁺, and Zn²⁺ at different concentration was also evaluated by texture analysis. The results reveal a strong dependence of the structural properties of different samples on their preparation conditions. A fine turning of the properties of the mixed sols is possible through the change of the temperature preparation and/or the polymer weight ratio. The texture properties of the mixed gels were also possibly influenced significantly by the cations. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

XJ-21菌株在胍胶压裂液体系中破胶驱油的复合性能研究

在储层压裂改造过程中,胍胶压裂液体系低温破胶难,储层改造效果差,是新疆油田油藏开发亟待解决的关键技术难题。本文针对这一技术难题,将微生物强化采油技术应用于压裂液体系中,从新疆油田吉7井区烧房沟组采集到油泥,通过对样品中微生物的富集培养及分离后,筛选得到一株能够高产生物表面活性剂的菌株,将其命名为XJ-21。结合菌落形态观察、革兰氏染色及16S rRNA序列分析结果,XJ-21菌株被鉴定为枯草芽孢杆菌（Bacillus subitlis）。傅里叶变换红外光谱（FTIR）分析确定XJ-21代谢产物中的生物表面活性剂与环脂肽类结构一致。XJ-21菌株与外源ZW-027菌株复配后,复配体系对油藏环境条件具有广泛适应性,不仅在温度为35~55 ℃的范围内可以产生生物酶使胍胶冻胶破胶,还可在50 ℃的条件下降低样品所在区块的原油黏度,降黏率可达95.45%。在水驱后,使用复配体系驱油与仅用水驱技术相比可以提高10.14%的驱油效率。     

Preparation and characterization of carboxymethyl konjac glucomannan/sodium montmorillonite hybrid films

Carboxymethyl konjac glucomannan (CKGM)/ sodium montmorillonite (MMT) hybrid films of various compositions were prepared by casting from a polymer/silicate water suspension. The structure and properties of the hybrid films were investigated by wide angle X‐ray diffraction (WAXD), transmission electron microscopy (TEM), attenuated total reflection infrared spectroscopy (ATR‐IR), differential scanning calorimetry (DSC), and tensile tests. The results from WXRD and TEM indicated that an intercalated CKGM/MMT nanocomposite film was obtained by polymer solution intercalation. WXRD and DSC showed that the high‐T_m crystal phase was induced by the presence of lower MMT loading, but the T_m of the hybrid films became weak with the increase of MMT content due to the polymer confinement. The hybrid films showed higher thermal stability and mechanical properties than that of the neat polysaccharide due to the strong interaction between hydroxyl and carbonyl group of CKGM and the silicate layer of MMT. Furthermore, the degree of swelling of the hybrid films was investigated in acidic buffer solutions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2954–2961, 2007     

Synthesis and characterization of grafted carboxymethyl guar gum

Graft copolymers of carboxymethyl guar gum (CMGG) and polyacrylamide (PAM) have been synthesized by grafting polyacrylamide chains onto carboxymethyl guar gum backbone using a ceric‐ion‐induced solution polymerization technique. By varying the amount of initiator, three different grades of graft copolymers are synthesized. The characterization of graft copolymer is carried out by FTIR, NMR, intrinsic viscosity measurement, SEM, SLS, DTG, and rheology. A comparison of flocculation efficiency of CMGG and its graft copolymer shows that the graft copolymer exhibits better flocculation performance. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Carboxymethylation of Cassia occidentalis seed gum

The seeds of Cassia occidentalis, an annual weed occurring throughout India, are a rich source of galactomannan gum. The gum derived from seed endosperm can be utilized in a number of industries to replace conventional gums. With a view to utilize the gum for broader applications, carboxymethylation of Cassia occidentalis seed gum was carried out. The reaction conditions were optimized with respect to concentration of monochloroacetic acid, sodium hydroxide, solvent ratio, reaction time, and reaction temperature. Rheological studies of carboxymethyl gum exhibited relatively high viscosity and stability vis‐a‐vis unmodified Cassia occidentalis gum. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1606–1611, 2004