绿色化学品-改性淀粉的制备与应用研究进展

简要介绍了淀粉的结构特点,重点评述了改性淀粉如羧甲基淀粉、氧化淀粉、阳离子淀粉、交联淀粉、接枝淀粉、多元改性淀粉的改性和应用现状。指出改性淀粉作为许多工业的原辅料,其原料资源丰富,易生物降解,因此具有广阔的发展前景。     

The chemical nature of algal (Chlorella) starch and its estimation in whole cells

The estimation of the starch content of chlorella cells was based on the sonication of whole cells in 2M NaOH followed by heating to solubilise the starch. The starch content of the solution was estimated by measurement of the glucose equivalents formed by acid hydrolysis. The starch content of the neutral solution was estimated by measuring light absorbance of its blue complex with iodine. The chlorella starch was purified from cells which had been disrupted in a French press, and the starch was solubilised by boiling with water. The starch was deproteinised, desalted and finally precipitated with ethanol before drying. This purification procedure avoided alkali extraction which degrades the starch. β-Amylase digestion of the purified starch was found to convert 67% of it to maltose. The purified starch gave a bright blue complex with iodine with peak absorbance at 590 nm.     

Preparation and properties of biodegradable poly(butylene succinate)/starch blends

The vital differences between the use of untreated starch and gelatinized starch in blends with poly(butylene succinate) (Bionolle) were thoroughly examined in this study. The melting temperature decreased slightly with increasing dosages of untreated and gelatinized starch. The added starch perhaps tended to disrupt the intermolecular hydrogen bonding within the Bionolle matrix. On the other hand, a large increase in the crystallinity was seen with the addition of starch. Starch appeared to play a nucleating role in the blends. The trend of the glass‐transition temperature decreasing with the starch level was similar to the trend of the melting temperature. For the same starch content, the glass‐transition temperature showed some variations. For blends containing a certain amount of gelatinized starch, the thermal stability remained to a certain degree but continued to decrease. This was ascribed to the relatively low heat stability of starch. As for the mechanical properties, a significant increase in the tensile strength (up to 2 times) was observed when untreated starch was replaced with gelatinized starch in the blends. Similarly, the tear strength increased up to 1.5 times if gelatinized starch was employed. Apparently, the gelatinization of starch was efficiently achieved for promoting its compatibility with Bionolle. In all cases, the mechanical properties of Bionolle blended with gelatinized starch were better than those of Bionolle blended with untreated starch. A morphological investigation provided evidence in support of these findings. This relatively low‐cost gelatinization approach provides an alternative to a high‐cost compatibilizer approach for improving the performance of biodegradable blends. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 257–264, 2005     

机械活化对木薯淀粉醋酸酯化反应的强化作用

采用搅拌球磨机对木薯淀粉进行机械活化,以不同活化时间的木薯淀粉为原料,以醋酸酐为酯化试剂、甲磺酸为催化剂制备淀粉醋酸酯,并以取代度为评价指标,分别研究了机械活化时间、反应时间、反应温度、催化剂用量及醋酸酐用量对木薯淀粉醋酸酯化反应的影响. 结果表明,机械活化对木薯淀粉酯化反应有显著的强化作用,活化时间越长,取代度越高. 主要原因是机械活化使木薯淀粉紧密的颗粒表面和结晶结构受到破坏,降低了结晶度,酯化试剂更容易渗透到颗粒内部使淀粉醋酸酯化. 其他因素对淀粉酯化反应的影响规律受活化时间的制约,活化时间越长,酯化反应对反应温度、催化剂及醋酸酐浓度的依赖性越低. 并利用红外光谱对木薯淀粉、活化淀粉及高取代度淀粉醋酸酯的结构进行了表征.     

Tensile properties,morphology, and biodegradability of blends of starch with various thermoplastics

In the present study, blends of starch with different thermoplastics were prepared by a melt blending technique. The tensile properties and morphology of the blends were measured. It was found that with increasing starch content in starch/ionomer blends, the tensile strength and modulus increase. But for starch/low‐density polyethylene (LDPE) and starch/aliphatic polyester (APES) blends, tensile strength and modulus decrease with increasing the starch loading. Elongation at break values of all the blend systems decrease with increasing starch loading. The scanning electron micrographs (SEM) support the findings of tensile properties. Better homogeneity is observed in starch/ionomer systems compared with that in starch/APES and starch/LDPE systems. Up to 50% starch content, the starch/ionomer blends appear as a single phase. The extent of phase interactions of starch/APES system lies in between the starch/LDPE and starch/ionomer systems. From the biodegradability studies of the blends it was found that, although the pure LDPE and ionomer are not biodegradable, the starch/LDPE and starch/ionomer blends are biodegradable with an appreciable rate. The rate of biodegradation of the starch/APES is very high as both the components are biodegradable. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2907–2915, 2002     

Thermogravimetric determination of starch content in starch–polyethylene blend films

Thermogravimetric analysis as a technique for rapid determination of starch content in LDPE/starch blend films was investigated. The percent weight loss in a specified temperature range, under a constant heating rate, correlated well with the starch content of films in the range of 0–12 wt % starch, as determined by chemical analysis. The method was used to estimate the residual starch content of LDPE/starch films, containing approximately 6.0% starch, exposed under several biotic exposure conditions. Generally 87–88% of the initial starch content was present in the films after different types of environmental exposures.     

Starch Granules in Arabidopsis thaliana Mesophyll and Guard Cells Show Similar Morphology but Differences in Size and Number

Transitory starch granules result from complex carbon turnover and display specific situations during starch synthesis and degradation. The fundamental mechanisms that specify starch granule characteristics, such as granule size, morphology, and the number per chloroplast, are largely unknown. However, transitory starch is found in the various cells of the leaves of Arabidopsis thaliana, but comparative analyses are lacking. Here, we adopted a fast method of laser confocal scanning microscopy to analyze the starch granules in a series of Arabidopsis mutants with altered starch metabolism. This allowed us to separately analyze the starch particles in the mesophyll and in guard cells. In all mutants, the guard cells were always found to contain more but smaller plastidial starch granules than mesophyll cells. The morphological properties of the starch granules, however, were indiscernible or identical in both types of leaf cells.     

个人护理产品中的专用淀粉（英）

阐述了天然淀粉转化成化妆品基本成分－专用淀粉的物理、化学改性方法及其使用优点。利用物理方法处理后的专用淀粉具有易溶于冷水、易溶解等优点，化学方法处理后的专用淀粉具有更好的黏性，可制备高浓度溶液，涂抹性良好等优点。在化妆品中使用专用淀粉可提高乳液、膏霜及粉末的外观，减少油腻感，赋予肌肤柔软、滑爽的感觉，同时可将不易添加的活性成分通过其包囊作用加入产品配方中。     

绿色改性淀粉絮凝剂的研究与应用

淀粉是一种比较理想的绿色试剂原材料。改性淀粉絮凝剂具有绿色、无毒、价廉、易于生物降解等优点。针对接枝类改性淀粉絮凝剂、离子化改性淀粉絮凝剂如淀粉醚类化合物以及淀粉黄原酸脂类等天然改性淀粉絮凝剂的研究进展及在水处理中的应用进行了综述。指出加强利用我国丰富的淀粉资源,开发出绿色、无毒、高效、价廉的改性淀粉绿色絮凝剂,以满足处理各种废水的不同需要,具有极其重要的现实意义。     

不同直链含量热塑性淀粉的制备及性能研究

利用转矩流变仪,以丙三醇为增塑剂对不同来源的淀粉进行改性制备热塑性淀粉（TPS）。采用X射线衍射仪（XRD）、热重分析仪（TG）、水接触角测量仪、傅里叶变换红外光谱仪（FTIR）和扫描电子显微镜（SEM）等对获得的热塑性淀粉进行了表征。结果表明,4种热塑性淀粉均含有颗粒状和颗粒状碎片,并且在热塑性木薯淀粉中所含比例更高;淀粉在增塑过程中达到稳态的扭矩依次为木薯淀粉（23 N·m）>玉米淀粉（21 N·m）>马铃薯淀粉（17.8 N·m）>蜡质玉米淀粉（15.2 N·m）,这与不同种类来源淀粉的直链淀粉比例差异直接相关;不同类型的淀粉与增塑剂形成氢键的能力存在差异,蜡质玉米淀粉的能力最强;4种热塑性淀粉的亲水性依次为热塑性木薯淀粉（75.9 °）>热塑性玉米淀粉（69.2 °）>热塑性马铃薯淀粉（67.9 °）>蜡质玉米淀粉（64.9 °）。     

The characterization of granule structural changes in acid-thinning starches by new methods and its effect on other properties

Acid-thinned starches (ATSs) have been prepared directly from hydrochloric acid-modified corn starch. The fracture mechanism of starch granule was investigated using scanning electron microscopy combined with laser particle size analysis. And the extent of ATSs chain was also first characterized using X-ray photoelectron spectroscopy. The properties of ATS were tested by X-ray diffraction, differential scanning calorimetry, thermo gravimetric analysis, and rotational viscometry. Native starch and ATSs exhibit different structures and properties. Amorphous regions of corn starch, located in the interior of the starch granule, are preferentially hydrolyzed and can lead to starch particle fracture. The relative C=O content in the ATSs are increased, indicating that the acid thinning makes the starch molecules shorter, and the fracture extent of the starch molecular chains was 240.86 and 608.97%, respectively. Acid thinning does not change the starch crystal pattern or its basic composition, but it does increase the degree of crystallinity. Compared to the native corn starch, ATSs has a higher gelatinization temperature and a lower enthalpy of gelatinization. The acid thinning treatment drastically reduces the hot paste viscosity of the starch.     

新型脲-双醛淀粉粘合剂的制备

将淀粉改性制得性能优异的双醛淀粉 ,代替甲醛与尿素缩合反应 ,合成出全新无毒的脲 -双醛淀粉胶粘剂。讨论了双醛淀粉与尿素的反应机理 ,并对二者反应的影响因素进行概括分析     

荔枝核淀粉提取工艺及其性质的研究

以荔枝核为原料 ,提取了其中的淀粉 ,并对其进行了纯化。对所得荔枝核淀粉的性质进行了研究 ,其中包括荔枝核淀粉的含量、淀粉中链淀粉和还原糖的含量 ,以及淀粉的颗粒形貌、溶解度、淀粉中的单糖组成。由于荔枝核的颜色较深 ,因此对荔枝核淀粉的最佳脱色条件也进行了研究 ,从而得到了一种性质较好的、较实用的淀粉     

淀粉基吸附剂的制备及应用研究进展

淀粉作为仅次于纤维素的可再生性资源,具有价廉易得、可降解性和能够较容易地利用生化方法转变成有用的衍生物等特点。长期以来世界各国都十分重视淀粉资源的开发利用研究,尤其是通过对淀粉改性制备新的天然高分子吸附剂一直是科技工作者的研究热点。综述近年来淀粉基吸附剂的研究进展,并简要介绍了多孔淀粉、环糊精、接枝共聚淀粉、淀粉黄原酸酯、淀粉氨基甲酸酯、羧甲基淀粉等的制备、结构性能及应用方面的基本研究状况,展望了其发展前景。     

Multilayer assembly of ionic starches on old corrugated container recycled cellulosic fibers

In this study, old corrugated container recycled fibers were treated with polyelectrolyte multilayers consisting of biopolymer cationic starch with two degrees of substitution (DS) each in combination with one anionic starch. Pulp zeta potential, paper strength and the thin layer ellipsometry technique were applied to examine the influence of cationic starch DS on the formation of polyelectrolyte multilayers. The results indicated a significant interaction between the DS of cationic starch and the number of ionic starch layers formed. When low‐DS cationic starch was used, the pulp zeta potential and the paper strength increased significantly in assembling the first cationic layer. However, in depositing high‐DS cationic starch a greater zeta potential and a stronger influence on the paper strength were observed with a larger number of starch layers. This was confirmed by thin layer ellipsometry when a greater thickness of multilayers was achieved by employing high‐DS cationic starch to form a higher number of layers. © 2017 Society of Chemical Industry     

高淀粉含量玉米淀粉膜的制备及结构性能研究

为改善原淀粉膜的脆性和成膜性,以甘油为增塑剂、采用高速搅拌及流延法制备了高淀粉含量的玉米淀粉膜.研究了甘油增塑前后玉米淀粉膜的热性能、显微观察及结晶结构,以及甘油的添加量对淀粉糊的流变性及淀粉膜的机械性能影响.结果表明甘油塑化玉米淀粉膜的α型结晶结构被破坏,并随甘油量的增加玉米淀粉膜的结晶度下降;甘油塑化的淀粉糊为假塑性流体,其黏度随剪切速率的增加而降低.当淀粉/水质量比为0.06时,甘油加入量为淀粉质量的40%时,甘油塑化淀粉膜的综合力学性能较好.     

Influence of starch on the properties of carbon‐black‐filled styrene–butadiene rubber composites

The influence of starch on the properties of carbon‐black‐filled styrene–butadiene rubber (SBR) composites was investigated. When the starch particles were directly melt‐mixed into rubber, the stress at 300% elongation and abrasion resistance decreased evidently with increasing starch amount from 5 to 20 phr. Scanning electron microscopy observations of the abrasion surface showed that some apparent craters of starch particles were left on the surface of the composite, which strongly suggested that the starch particles were large and that interfacial adhesion between the starch and rubber was relatively weak. To improve the dispersion of the starch in the rubber matrix, starch/SBR master batches were prepared by a latex compounding method. Compared with the direct mixing of the starch particles into rubber, the incorporation of starch/SBR master batches improved the abrasion resistance of the starch/carbon black/SBR composites. With starch/SBR master batches, no holes of starch particles were left on the surface; this suggested that the interfacial strength was improved because of the fine dispersion of starch. Dynamic mechanical thermal analysis showed that the loss factor at both 0 and 60°C increased with increasing amount of starch at a small tensile deformation of 0.1%, whereas at a large tensile strain of 5%, the loss factor at 60°C decreased when the starch amount was varied from 5 to 20 phr. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Morphology,thermomechanical properties,and biodegradability of low density polyethylene/starch blends

The biodegradability of low density polyethylene (LDPE)/starch and LDPE/starch/starch acetate (STAc) blends was tested and observed to be dependent on STAc content. The binary and ternary blends containing up to a maximum concentration of 30% starch were examined for their thermal, mechanical, and morphological properties. The blends with no STAc or 2.5% STAc show almost no adherence of two phases. With 10% STAc, dispersion of starch was observed to increase with some adherence to LDPE. Tensile strength, elongation at break, and Izod impact strength of the blends decreased with increased starch content. However, incorporation of STAc along with starch improved all these properties, particularly elongation at break and toughness. The melt flow index was also improved on partial substitution of starch by STAc. Maximum biodegradability was observed for the blends containing 30% (starch + STAc). Cell growth was observed to increase with increasing concentration of (starch + STAc) in the blends. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 2791–2802, 1999     

Characterization of different starch types for their application in ceramic processing

Starch is a frequently used pore-forming agent in ceramic technology. Moreover, it can take over the function of a body-forming agent in a recently developed process, called starch consolidation casting. Upon firing the starch polymers are burnt out without residues and leave a pore structure determined by the type of starch applied. In this paper, five commonly available starch types (potato, wheat, tapioca, corn and rice starch) are characterized with respect to size and shape. Size distributions are measured via laser diffraction and microscopic image analysis. Rice starch is found to be the smallest type (median size 4.4–4.8 μm), potato starch the largest (median size 46–49 μm) and the other types intermediate (median size 12–21 μm). The distribution is narrow for corn and tapioca starch (span approximately 1.1), while potato, wheat and rice starch are relatively polydisperse (span approximately 1.35–1.65). The shape of the starch granules is most anisometric for potato starch (average aspect ratio 1.3–1.4). All other starch types, although possibly of polyhedral shape (tapioca, corn and rice starch), are more isometric, i.e. very close to an average aspect ratio of 1.     

Preparation and characterization of kaolin/starch foam

The objective of this work was to study the effect of the kaolin content on the properties of starch foams. The kaolin/starch foams were made with kaolin contents that ranged from 0 to 15 m% by baking in a hot mold. The starch and kaolin/starch foams were stored at room temperature with a relative humidity (RH) of 55% for 7 days prior to testing. An increase in the kaolin content increased the foam density. The izod impact strength increased up to 1151.37 J/m² at the highest kaolin content (15 m%). The improvement was about five times the izod impact strength of pure starch foam. Moreover, the presence of any kaolin reduced the water absorption ability of the starch foam. Scanning electron microscopy revealed that kaolin increased the size of the starch foam cells and was itself well dispersed. Kaolin/starch foams showed a higher thermal stability than pure starch foam.