共查询到19条相似文献,搜索用时 359 毫秒
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淀粉烯丙基化预处理型PMA接枝淀粉的研究 总被引:1,自引:1,他引:0
研究淀粉烯丙基化预处理型PMA接枝淀粉的制备方法及性能.通过对淀粉原料进行醚化预处理,在淀粉大分子上引入碳-碳双键,再将这种含有碳-碳双键的淀粉与丙烯酸甲酯单体进行接枝共聚合反应,大幅度提高了淀粉与丙烯酸甲酯单体接枝共聚合反应的接枝效率,改善了烯丙基化预处理型PMA接枝变性淀粉浆料(AS-g-PMA)的上浆性能.研究结果表明,当淀粉醚化取代度在0.01~0.043范围内时,这种醚化预处理方法可以使淀粉对丙烯酸甲酯的接枝效率比直接接枝提高10%~20%,并能显著改善接枝淀粉浆料对纤维的粘附性能以及浆膜性能.试验证实AS-g-PMA型接枝变性淀粉浆料的醚化取代度以0.011~0.023为宜. 相似文献
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探讨接枝单体对马来酸酐酯化预处理型丙烯酸酯接枝淀粉浆料性能的影响。将马来酸酐酯化淀粉分别与丙烯酸甲酯、丙烯酸乙酯及丙烯酸丁酯进行接枝共聚合反应,制备出马来酸酐酯化预处理型丙烯酸酯接枝淀粉浆料,并测试了各接枝淀粉浆料的接枝效率、接枝率、单体转化率、黏度、黏度热稳定性、黏附性能及浆膜性能。试验结果表明:丙烯酸乙酯较适宜作为制备马来酸酐酯化预处理型丙烯酸酯接枝淀粉浆料的接枝单体。 相似文献
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酸解,酯化预处理对接枝淀粉浆料上浆性能的影响 总被引:2,自引:0,他引:2
本文在接枝变性淀粉浆料接枝链分子结构和合成路线成果的基础上,通过对淀粉实施酸解或酯化预处理变性,进一步提高了接枝变性淀粉浆料对细号涤/棉纺纱的上浆性能。研究结果表明,淀粉分子量的降解和乙酰化这两种预处理变性方式都是有益的。 相似文献
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摘要:采用不同投料比,制备一系列具有不同取代度的马来酸酐酯变性淀粉,测试其浆液黏度、浆膜及黏附性,以明确马来酸酐酯化变性对淀粉浆料性能的影响。通过与酸解淀粉及醋酸酯淀粉的比较,评价了马来酸酐酯化淀粉的上浆性能。结果表明:马来酸酯化变性能够有效增加淀粉浆膜的断裂伸长和断裂功,提高对涤纶及棉纤维的黏附性,改善退浆性。当变性程度相近时,马来酸酐酯化淀粉浆料的性能优于醋酸酯淀粉。从黏附力、浆膜性能、反应效率等方面判断,马来酸酐酯化淀粉的取代度以0.036为宜;制备方法是:首先应采用适当的方式对淀粉原料降黏,然后将淀粉质量25%的马来酸酐缓慢加入到淀粉水分散液中,控制反应体系的pH7.5~8.5,最后在30℃下搅拌反应1h。 相似文献
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降解淀粉与乙烯基单体AA-AN-AM接枝共聚物复鞣剂的合成及应用研究 总被引:4,自引:2,他引:4
氧化降解的玉米淀粉与丙烯酸(AA)、丙烯腈(AN)和丙烯酰胺(AM)在引发剂(NH4)2S2O8作用下进行了接枝共聚合反应,制得改性淀粉复鞣剂。研究了单体浓度及配比、引发剂浓度等因素对接枝共聚合反应的接枝率、单体转化率、接枝效率等的影响,用红外光谱对接枝共聚物的结构进行了分析表征,同时进行了应用实验。 相似文献
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为研究接枝淀粉理化特性与其浆用性能的关联,通过微波辅助法将阳离子淀粉与丙烯酰胺、甲基丙烯酸-β-羟乙酯和丙烯酸丁酯接枝共聚,制备出不同接枝率(GR)的接枝阳离子淀粉(GCS),通过FT-IR和XRD表征产物结构。研究了GCS的理化特性与浆纱性能。结果表明,在一定接枝率范围内,GCS的理化性能改善,表现为水合能力、流变性能增强,抗老化性、透明度提高,而过高的接枝率会导致淀粉理化性能恶化。GCS浆纱性能随接枝率增大而提高,当接枝率为13.58%时,浆纱断裂强力、减伸率和耐磨性达到最优值,随着接枝率进一步增大,浆纱性能指标下降。研究结果还表明接枝淀粉理化特性的改善与其浆用性能的提高密切相关。 相似文献
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为改善淀粉浆液对涤棉混纺纱的黏附性和浆膜的力学性能,采用辣根过氧化物酶(HRP)/乙酰丙酮(ACAC)/过氧化氢(H2O2)引发体系,催化酸解淀粉接枝丙烯酸甲酯。通过傅里叶红外光谱、扫描电子显微镜和X射线衍射对接枝淀粉进行表征,并分析其流变特性。结果表明,在HRP酶催化作用下丙烯酸甲酯与未糊化酸解淀粉发生接枝共聚反应,且对酸解淀粉结晶度影响不大;淀粉接枝改性后浆液黏度增大,黏弹性增加,呈现更具弹性的流体特征;相比于酸解淀粉,含有柔性接枝支链的淀粉浆液对涤/棉黏附性有明显提高,浆膜断裂伸长率和断裂强度均有增加,力学性能得到改善。 相似文献
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In order to enhance the grafting efficiency of graft copolymerization of granular cornstarch with acrylic acid (AA) for improving the adhesion and film properties of starch‐g‐poly(acrylic acid) used as sizing agent, the esterification of hydrolyzed starch with acryloyl chloride was applied before graft copolymerization. The influence of three common initiators on the copolymerization were also studied. The initiators included ceric ammonium nitrate [Ce(NH4)2(NO3)6], hydrogen peroxide/ferrous ammonium sulfate [H2O2/FeSO4 · (NH4)2SO4], and potassium persulfate/sodium bisulfite [K2S2O8/NaHSO3]. It was found that acryloylation of starch before the copolymerization was an effective method for substantially enhancing the grafting efficiency and improving the performances such as adhesion‐to‐fibers and mechanical properties of grafted starch film. The acryloylation could increase the efficiency to 67–81% when the degree of substitution (DS) of acryloylated starch ranged from 0.010 to 0.036. The adhesion to polyester and cotton fibers reached their maximum at DS = 0.010 and 0.022, respectively. Strong and tough film was obtained when the DS value was in a range of 0.010–0.022. H2O2/FeSO4 · (NH4)2SO4 redox system was more appropriate for initiating the copolymerization of acryloylated starch with AA. 相似文献
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Starch maleate was prepared by microwave‐assisted reactions. Microwave‐assisted esterification in a dry medium for 5 min gives a reaction efficiency of 98%. Influences of reaction time, reagent molar ratio and water content of starch on the degree of substitution (DS) of the product and reaction efficiency were investigated. The structure of starch maleate was characterized by FTIR and NMR spectroscopy. Changes in the starch granules before and after modification were studied by scanning electron microscopy (SEM). Compared with the conventional heating synthesis method, microwave‐assisted synthesis in a dry medium is rapid and energy saving with high reaction efficiency. 相似文献
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针对一些家纺面料布机开车情况不理想,效率高低差距较大,平均效率偏低等问题,提出选用DF868高性能接枝淀粉浆料对纱线上浆来改善织造性能。文章简要介绍了DF868高性能接枝淀粉浆料的物性指标,并设计了一组对比上浆织造实验。结果表明:在细支高密府绸上用DF868浆料取代部分PVA上浆,织造断头明显减少,织机效率得到提高,不但成本降低,生产效率也得到提高,质量明显改善,而且对环境无污染。 相似文献
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Pregelled starch (PS) was subjected to acid hydrolysis using phosphoric acid to prepare pregelled starches having different molecular sizes. The degraded pregelled starches were carboxymethylated at different reaction times. The carboxymethyl derivatives were grafted with either methacrylamide (MAam) or methacrylonitrile (MAN) as vinyl monomers using ceric ammonium nitrate (CAN) as initiator. Suitability of the new graft derivatives of pregelled starch as sizing agent of cotton yarns was studied. It is shown by the data that the extent of carboxymethylation, expressed as carboxyl content, increases by increasing the extent of hydrolysis and reaction time. Furthermore, the graft yield, expressed as mmol MAam or MAN monomer/100 g graft copolymer (grafted carboxymethylated pregelled starch or grafted carboxymethylated hydrolyzed pregelled starch) increases with increasing extent of carboxymethylation and degree of hydrolysis and follows the order: MAam > MAN. In addition cotton yarns sized with grafted carboxymethylated hydrolyzed pregelled starch – irrespective of the grafting monomer used – have better mechanical properties (tensile strength, elongation at break, and abrasion resistance) than hydrolyzed pregelled starches, carboxymethylated pregelled starch and carboxymethylated hydrolyzed pregelled starches. 相似文献