共查询到19条相似文献,搜索用时 109 毫秒
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交联氧化淀粉胶黏剂的制备及性能研究 总被引:3,自引:0,他引:3
采用交联氧化法,先用高锰酸钾氧化可溶性淀粉制得低取代度氧化淀粉,再用戊二醛交联成交联氧化淀粉主剂,最后在高温无水条件下加入甲苯二异氰酸酯(TDI)得到氨基甲酸酯交联氧化淀粉胶黏剂。初步探讨了交联氧化机理,分析了交联氧化淀粉胶黏剂的影响因素,利用红Pb(IR)、扫描电镜(SEM)对其进行了表征,对产品的各项性能进行测试研究。结果表明,氧化程度影响其粘结性能,低取代度氧化淀粉粘结性好,且有利于淀粉进一步交联反应,交联提高淀粉耐水性,TDI能够显著提高氧化淀粉的耐水性和粘结强度。当淀粉浓度为10%,高锰酸钾用量为0.0290g,戊二醛用量为2mL,TDI用量为1mL时,制得的交联氧化淀粉胶黏剂的耐水时间为24d。 相似文献
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水处理剂合成中交联淀粉制备工艺的优化 总被引:6,自引:0,他引:6
以玉米淀粉为原料,研究交联淀粉的合成,性质及在水处理中的应用,在用环氧氯丙烯作交联剂,氢氧化钠催化的条件下,综合考查多个因素,如交联剂投加量,淀粉浓度,反应时间,温度,中性盐等对交联反应的影响。最终确定了作为重金属捕集剂原料的高交联淀粉的合成条件。在本实验提出的合成条件下,能最终合成出满足处理要求的中间产物3-氯-2-羟基丙烯基交联淀粉(HHCS)以及目标产物DDTC-螯合淀粉。 相似文献
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交联氨基淀粉的制备及其螯合性能研究 总被引:4,自引:0,他引:4
以玉米淀粉为原料,用环氧氯丙烷作交联剂合成了高交联淀粉,在高氯酸引发下,以环氧氯丙烷为醚化剂合成了醚化淀粉———3-氯-2-羟基丙烯基交联淀粉,碱性条件下通过与乙二胺的胺化反应制备了对重金属具有螯合性能的氨基淀粉衍生物。讨论了引发剂用量、交联淀粉含水质量分数、醚化温度、时间等对醚化淀粉含氯质量分数的影响,以及氨基淀粉合成过程中醚化淀粉含氯质量分数、乙二胺用量、反应温度等对氨基淀粉氨基含量的影响。结果表明,以含水质量分数为11%的交联淀粉为原料,90℃时n(环氧氯丙烷):n(交联淀粉)=2.5 1,反应8h,可以得到氯质量分数为13%的醚化淀粉。60℃时醚化淀粉与过量的乙二胺反应可以得到氨基含量为1.98mmol/g的氨基淀粉。这种氨基淀粉对铜有很强的螯合能力,在pH为3.5~5.0范围内,处理铜质量浓度为45.00mg/L的溶液,可使残留铜质量浓度<0.15mg/L。 相似文献
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考察了不同含水量的木薯淀粉经不同形式(敞口和封口形式)微波辐射的温度变化曲线及其多层次结构.结果表明:无论以那种形式辐射,木薯淀粉样品含水量越低,样品温度升高幅度越大,且都会出现等温转换,含水量越高等温转换时间越长,敞口辐射较封口辐射的等温转换更显著; FTIR结果显示,微波辐射不破坏木薯淀粉分子的化学键,没有新的化合物产生,红外结晶指数略有降低;偏光显微镜和光学显微镜的结果显示,木薯淀粉的结晶结构有所变化,而其形态结构没有变化.这些结果表明,经微波加工的木薯淀粉食品对人或其他生物是安全的. 相似文献
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Waranyou Sridach Sunan Jonjankiat Thawien Wittaya 《Journal of Adhesion Science and Technology》2013,27(15):1727-1738
The properties of tapioca starch adhesives were improved by cross-linking and the cross-linked adhesive compared with pure tapioca starch and poly(vinyl alcohol) adhesives. The effect of starch ratio, type of PVOH, and adding citric acid were important factors on the cross-linked adhesives. Wood adhesives made from cross-linked PVOH/starch were prepared by PVOH and tapioca starch, using hexamethoxymethyl melamine (HMMM) and citric acid (CA) as a cross-linking agent and catalyst, respectively. The effect of CA, PVOH/starch ratio, and type of PVOH such as medium (M PVOH) and high molecular weight (H PVOH) were investigated. The condition of the cross-linking reaction was 175?°C for 15?min. The structural properties of cross-linked adhesive were investigated by FT-IR spectroscopy. The results were confirmed in terms of thermal properties with a differential scanning calorimeter (DSC) and the shear strength of the adhesive. The cross-linked adhesive resulted in the increase of T g and showed good blend compatibility with all of the cross-linked adhesives. The adhesive strength significantly increased when using CA as a catalyst in the cross-linking reaction. The optimum contents of the cross-linked PVOH/starch adhesives were 1:1.8 for M PVOH and 1:0.5 for H PVOH. 相似文献
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对木薯淀粉进行了复合变性表面化学修饰,利用X射线衍射、扫描电子显微镜(SEM)和红外光谱分析了产物的结构特征变化。结果表明,酯化反应不仅发生在无定形区,而且也破坏了淀粉分子的结晶区,羟基被取代,改善了原淀粉的疏水性.所得到的产品能更好地应用于淀粉基生物降解塑料的开发。 相似文献
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乙醇胺塑化木薯淀粉可生物分解材料研究 总被引:1,自引:0,他引:1
用乙醇胺对木薯淀粉进行塑化,制备了乙醇胺塑化木薯淀粉(EPTS)可生物分解材料。扫描电子显微镜(SEM)表明,原木薯淀粉颗粒被破坏,乙醇胺已经渗透到木薯淀粉颗粒内部,成功地塑化了木薯淀粉,使其成为均一连续相;将不同乙醇胺含量的EPTS在相对湿度50%(RH=50%)的环境下保存14 d,力学测试得出:w(乙醇胺)=30%塑化的EPTS拉伸应力达到7.48 MPa,应变为108%,杨氏模量和断裂能分别由乙醇胺塑化玉米淀粉(EPCS)可生物分解材料的75.32 MPa、2.305 N.m上升到EPTS的93.27 MPa、2.319 N.m,EPTS力学性能明显改善;热失重分析(TGA)显示,热失重w(EPTS)=15.89%、w(EPCS)=17.18%,EPTS热稳定性更好;材料的吸水实验显示EPTS耐水性能好于EPCS。 相似文献
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Ju Dong Lee 《Chemical engineering science》2007,62(23):6548-6555
This work investigated the kinetic inhibiting effect of a number of cationic starches in hydrate formation experiments with methane and methane/ethane and methane/propane gas mixtures. The starches were found to exhibit a very weak inhibiting effect except for tapioca starch which increased the induction time (delay of onset of crystallization) by an order of magnitude. The addition of polyethylene oxide (PEO) was found to further enhance the performance of tapioca starch as well as some of the other starches. Finally, the presence of tapioca starch and PEO was found to suppress the memory effect. The results were interpreted based on a mechanism proposed by Zeng et al. [2006a. Effect of antifreeze protein on nucleation, growth and memory of gas hydrates. A.I.Ch.E. Journal 52(9), 3304-3309; 2006b. Effect of antifreeze proteins on the nucleation, growth and the memory during tetrahydrofuran clathrate hydrate formation. Journal of the American Chemical Society 128, 2844-2850] whereby the starches interfere with nucleation through interactions with heterogeneous nucleation sites. 相似文献
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The tilapia fileting industry generates large amounts of nutritionally significant waste material, and the recovery of this material is important. The manufacture of restructured products from mechanically recovered fish meat (MRFM) obtained from tilapia fileting allows the use of proteins of high biological value that would otherwise be discharged into the environment. The objective of this study was to evaluate the effect of washing cycles (either one cycle or five cycles) and of the addition of tapioca starch (20% vs. a no-starch control) on the characteristics of surimi obtained from MRFM produced by the tilapia industry and destined for use in restructured products. To evaluate the quality attributes of the product, the structure of a surimi protein matrix and its relationship to selected physicochemical parameters and morphological characteristics was assessed. Both the number of washing cycles and the starch addition were found to influence the moisture, protein and lipid content of the MRFM surimi. Higher whiteness was found after five washing cycles. Because the tapioca starch acted as a stabilizer, the fat globules were more stable and well distributed, and an emulsion with better properties resulted. A homogeneous network of fat globules linked to the protein matrix by a layer of tapioca starch was formed. Another advantage of this approach is that tapioca starch is gluten free. This property is important for specific groups in the population, e.g., celiac-intolerant consumers. 相似文献