干法制备阳离子淀粉工艺研究及其特性分析

在碱催化剂存在下，以N-(2，3-环氧丙基)三甲基氯化铵(GTA)为阳离子化试剂，干法制备了季铵型阳离子淀粉。通过通用旋转实验研究了GTA与淀粉用量和GTA与NaOH用量之比、反应温度、反应时间以及反应体系中水的质量分数等诸因素对取代度和反应效率的影响，并确定了最佳反应条件：GTA与淀粉用量之比为0．057，NaOH与GTA用量之比为1．4，反应体系水的质量分数25％，反应温度80℃，反应时间3h，取代度高达0．046，反应效率为80，7％。阳离子淀粉透明度是92，3，取代度是0．042。     

干混法制备阳离子淀粉工艺方法研究

用醚化剂GTA与玉米淀粉在不加碱或只加催化量碱的情况下,进行反应以制备低取代度阳离子淀粉,研究了反应温度、反应时间、体系pH值、体系含水量、GTA用量对取代度、反应效率的影响.在不加碱的情况下,当淀粉的用量9.6g,GTA的用量0.4g,反应时间3h,温度控制在50℃,制得低取代度阳离子淀粉.所得的产物的取代度为0.037 9,反应效率为85.2%.其他条件不变,体系中加入2.5 mL pH值为9的水溶液,所得的阳离子淀粉的取代度为0.038 7,反应效率为86.8%.     

碱催化干法制备阳离子淀粉的研究

本实验以N-(2，3-环氧丙基)三甲基氯化铵(GTA)为阳离子化试剂，在碱催化剂存在的条件下，干法制备了季铵型阳离子淀粉。实验研究了GTA与淀粉用量之比、GTA与NaOH用量之比、反应温度、反应时间以及反应体系中水的质量分数等诸因素对取代度和反应效率的影响，最后用正交法确定了最佳工艺参数，结果表明：当使用1．87gGTA、1gNaOH、在温度80℃和反应时间2h条件下取代度可达到0．038。     

小麦阳离子淀粉制备工艺研究

以小麦淀粉为原料,以N-(2,3-环氧丙基)三甲基氯化铵(GTA)为醚化剂制备小麦阳离子淀粉;以取代度和反应效率为响应值设计5因素(GTA用量,氢氧化钠用量,加水量,反应温度,反应时间)3水平响应面实验,通过响应面实验得到最佳制备条件为:GTA加入量12mL,NaOH加入量为0.29g,加水量5mL,反应温度90℃,反应时间3.23h;另外还分析双因素间交互效应。     

醚化剂GTA的合成及其在干法制备阳离子淀粉中的应用

用环氧氯丙烷与三甲胺反应合成失水甘油基三甲基氯化铵 (GTA) ,研究了环氧氯丙烷的用量、反应介质对GTA收率的影响 ,然后将其与淀粉混合制备低、高取代度季铵型阳离子淀粉 ,研究了反应温度、反应时间、碱用量对取代度、反应效率的影响。     

纸张增强用阳离子化壳聚糖的合成

以NaOH为催化剂,2,3-环氧丙基三甲基氯化铵（GTA）为阳离子醚化剂,干法制备了高取代度的阳离子壳聚糖。研究了阳离子醚化剂的制备、NaOH用量、阳离子醚化剂用量、反应时间和反应温度对阳离子壳聚糖的得率和取代度的影响。实验结果表明,当壳聚糖用量为0．5g时,优化后的反应条件为1．41gGTA、0．005gNaOH、反...     

半干法制备阳离子淀粉的工艺优化

以玉米淀粉为原料,3-氯-2-羟丙基三甲基氯化铵(CTA)为醚化剂,在碱性条件下,采用半干法制备低取代度阳离子淀粉。采用Box-Behnken中心组合响应面设计,对半干法工艺进行优化,并分析反应温度、反应时间、碱的用量、体系含水量对阳离子淀粉取代度的影响。结果表明:回归方程能较好地预测取代度随工艺条件变化的规律,半干法制备低取代度阳离子淀粉工艺条件为:反应温度64.40℃,反应时间6.58 h,NaOH与醚化剂摩尔比2.12,体系含水量25.28%,在此条件下制得的阳离子淀粉取代度为0.051 9。     

微波干法制备阳离子淀粉及其絮凝性能的研究

以玉米淀粉和2,3-环氧丙基三甲基氯化铵(GTA)为原料,微波干法制备了用于污水处理的季铵盐型阳离子淀粉.结果表明:微波法可大大缩短反应时间,淀粉量10 g,当醚化剂用量1 g、辐射时间9 min和反应温度750℃时,可制得取代度为0.24的阳离子淀粉.然后研究阳离子淀粉絮凝性能,结果表明:pH8.22、温度50℃、絮凝剂用量0.4 g/100 ml时,阳离子淀粉用于污水的处理具有较好的絮凝效果.     

干法合成阳离子淀粉的研究

讨论了干法制备阳离子淀粉工艺中阳离子试剂、催化剂用量及反应温度、反应时间等因素对取代度和反应效率的影响。研究表明最佳工艺条件是:淀粉、醚化剂及NaOH加入量的质量比为50∶18∶5,淀粉含水量为34%,反应温度60℃,时间5h,可以制备出取代度为0.289,反应效率为75%的高取代度阳离子淀粉。     

水相中高取代度低黏度羧甲基淀粉的制备

羧甲基淀粉(CMS)是一种阴离子淀粉醚,广泛应用于医药、食品、纺织、石油钻探等领域。以玉米淀粉为原料,采用酸化-醚化复合变性的方法在水相中制备高取代度低黏度羧甲基淀粉(CMS),探讨了酸化时间、液固比、NaOH用量、ClCH2COOH用量、醚化反应时间、反应温度对羧甲基化过程的影响,研究发现,对原淀粉进行酸化,可以在不增加其它反应试剂用量的基础上提高产物的取代度(DS),但是酸化时间不应过长。同时得到了其他单因素变化时各自对产物取代度的变化趋势,为进一步优化反应条件提供了依据。     

微波半干法高取代度阳离子木薯淀粉制备及其对AKD的乳化性能

以3-氯-2-羟丙基三甲基氯化铵为醚化剂,采用微波半干法制备了低黏度阳离子氧化木薯淀粉,研究了醚化剂用量、氢氧化钠用量、乙醇用量、反应温度和反应时间对反应的影响,并对产品乳化AKD的性能进行了研究。研究结果表明,最佳反应条件为：醚化剂用量53%、氢氧化钠用量14%、醚化剂与氢氧化钠摩尔比1：1,并用氢氧化钠与乙醇配制成质量分数为8%的溶液,体系含水量为18.5%,反应温度为60℃,反应时间3h,产品取代度达到0.3906,反应效率85.53%。所得产品对AKD具有良好的乳化性能。     

阳离子糯玉米淀粉制备工艺

以特种糯玉米淀粉为原料,以N-(2,3-环氧丙基)三甲基氯化铵为阳离子化试剂,制备糯玉米阳离子变性淀粉,根据单因素的实验,选择N-(2,3-环氧丙基)三甲基氯化铵用量、氢氧化钠用量、加水量,反应温度、反应时间,五因素三水平正交实验设计,实验结果表明,糯玉米阳离子变性淀粉的最佳制备条件是:N-(2,3-环氧丙基)三甲基氯化铵用量为1mL,氢氧化钠用量为0.29g,加水量为5mL,反应温度为90℃,反应时间为3.23h;同时,本研究对样品进行了取代度分析。     

Preparation and Characterization of Some Cationic Starches

Three types of cationic starches were prepared via reacting starch with 3-chloro-2-hydroxypropyl amine, 1,1,1,n-Tris(3-chloro-2-hydroxypropyl) amine and glycidyl trimethyl ammonium acetate in presence of sodium hydroxide. The different factors affecting these reactions were investigated. These factors include sodium hydroxide/amine, amine/starch molar ratios, liquor ratio, reaction duration and temperature. The amination extent and amination reaction efficiency percent were traced by estimating the nitrogen content of the aminated starch. Characterization of the prepared cationic starches such as solubility, moisture content, anion-exchange capacity and metal ions sorption were studied.     

The Role of Reaction Parameters on the Preparation and Properties of Carboxymethyl Cassava Starch

The role of reaction variables on carboxymethylation of cassava starch was investigated using a statistically experimental design approach. The reaction was carried out in an isopropanol‐water mixture at 40°C for 3 h. The reaction parameters under investigation included water fraction in the reaction medium, the ratio of sodium hydroxide to anhydroglucose unit (AGU) and the ratio of sodium monochloroacetate (SMCA) to AGU. The dependent responses were degree of substitution (DS) of CMS and the reaction efficiency (RE) of the carboxymethylation. Carboxymethyl cassava starches with DS in the range of 0.01 to 0.86 were prepared. The result from regression analysis indicated that the most important factors in controlling the DS of CMS were sodium hydroxide and SMCA contents followed by water content. Response surface plots suggested that the optimal levels of sodium hydroxide and water content to achieve CMS with high DS were at the intermediate values. Similar effects of sodium hydroxide and water content were also observed on the RE while SMCA content had a negative effect; increasing SMCA content resulted in lower RE. The optimal conditions to achieve the highest DS and RE were found to be at a water content of 17–19% with a molar ratio of sodium hydroxide to AGU of 1.8–1.9 and a molar ratio of SMCA to AGU between 1.1–1.5. Carboxymethyl cassava starch with various DS was also prepared. The properties of CMS as affected by the degree of modification were also discussed.     

浓碱湿法变性淀粉的制备工艺

以玉米淀粉为原料,三偏磷酸钠、次氯酸钠、醋酸酐、环氧丙烷、3-氯-2-羟丙基三甲基氯化铵为改性剂,采用质量分数3%、6%和10%的氢氧化钠溶液在水相中制得变性淀粉,并研究了其理化性质。根据反应过程碱液消耗量和反应后淀粉乳总容积,计算出反应罐利用效率和用水量变化,研究显示,采用10%浓碱制备湿法变性淀粉可以提高反应罐的利用效率和生产能力5%~22%,减少工业废水排放量8%~34%,其中采用浓碱对于制备高效节水醋酸酯淀粉和阳离子淀粉效果尤为显著。该工艺突破了目前普遍采用低浓度碱液(质量分数2%~4%)制备湿法变性淀粉的瓶颈,为食品及工业上浓碱湿法变性淀粉的生产提供了理论基础。     

Effects of cationization on DSC thermal profiles,pasting and emulsifying properties of sago starch

Cationic sago starches were prepared using an aqueous alkaline process with different levels of cationic reagent 3‐chloro‐2‐hydroxypropyltrimethylammonium chloride (0.01–0.10 M ), sodium hydroxide (0.03–0.86 M ) and reaction temperature (30–62 °C). The degree of substitution (DS), reaction efficiency, thermal and pasting properties of cationic sago starches were analysed. Emulsifying and fat binding properties of native sago starch, cationized sago starch and commercial chitosan were compared at two different pH values (4 and 7). Degree of substitution increased with an increase in concentration of cationic reagent or NaOH, or reaction temperature. The reaction efficiency was proportional to the concentration of NaOH and reaction temperature but inversely proportional to the cationic reagent concentration. The highest DS and reaction efficiency achieved was 0.06 and 79%, respectively. The pasting temperature and gelatinization enthalpy of cationic starch (DS 0.06) were lower compared with native sago starch. Cationization increased the peak viscosity and breakdown of the starch paste but decreased the setback. The presence of cationic groups significantly increased emulsion stability, emulsion viscosity and fat binding capacity of sago starch. However, the cationic sago starch was still inferior to chitosan, which showed the highest emulsion stability, emulsion viscosity and fat binding capacity. There was no significant difference between the surface tension values of native and cationic sago starch and chitosan. The influence of pH on emulsifying properties was not significant. The emulsion stability of the cationic sago starch improved due to an increase in viscosity and fat binding capacity but not its surface active property. Copyright © 2004 Society of Chemical Industry     

干法制备氧化淀粉的工艺研究

以H_2O_2为氧化剂，在碱催化剂存在的条件下干法制备出氧化淀粉。并对反应温度、反应时间、反应体系水的质量分数、NaOH与淀粉的摩尔比和H_2O_2与淀粉的摩尔比对氧化淀粉羧基含量的影响进行了研究。在固定反应时间3h，以及H_2O_2与淀粉的摩尔比0.225的条件下，选择反应温度、反应体系水的含量、NaOH与淀粉的摩尔比为三因素，采用正交实验，确定出制备氧化淀粉的最佳工艺参数为：反应温度60℃、反应体系水的质量分数为26.5％、NaOH与淀粉的摩尔比为0.135。