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纸浆纤维与丙烯酰胺接枝共聚反应规律及产物结构与性能研究 总被引:4,自引:0,他引:4
采用铈离子引发纸浆纤维与丙烯酰胺的异相接枝共聚反应,研究了单体浓度、引发剂浓度、反应温度及时间等对单体转化率与接枝率的影响。用IR、TG、DSC、SEM、X-射线衍射,偏光显微镜等手段对接枝物的结构和性能进行了表征。结果表明,接枝物的热稳定性高于原纤维,接枝主要发生在纤维的表面和无定形区,对它的结晶性没有损害 相似文献
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海藻酸纤维的发展历史 总被引:1,自引:1,他引:0
海藻酸是从褐藻类植物中提取的一种天然高分子材料,是一种无毒、无害、可生物降解的纯天然绿色材料。以海藻酸为原料,通过湿法纺丝制备的海藻酸纤维可以应用于纺织、服装、医疗卫生等领域,是一种具有很高附加值的功能纤维材料。介绍了海藻酸纤维的生产工艺,总结了国内外有关海藻酸纤维的早期研究成果。 相似文献
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考察了各因素对木质素磺酸钙与丙烯酰胺接枝共聚反应的影响,并对产物的结构进行了红外光谱分析;此外,还对产品性能,如热稳定性、抗盐、抗钙能力进行了测试。接枝共聚反应的优化工艺条件为:m(木质素磺酸钙)∶m(丙烯酰胺)=1∶5,引发剂浓度为4.2×10-3mol.L-1,反应温度50℃,反应时间2h。接枝共聚物的红外谱图表明,木质素磺酸钙与丙烯酰胺之间发生了接枝共聚反应。接枝共聚物有一定的热稳定性,抗盐、抗钙能力较好。 相似文献
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以自制海藻酸纤维为吸附剂,考察了吸附剂用量、溶液温度、吸附时间和溶液pH值等因素对海藻酸纤维吸附碱性品红的吸附效果的影响。结果表明:脱色率随海藻酸纤维加入量的增加而提高,随着溶液温度升高而迅速下降;加酸或加碱都不利于海藻酸纤维对碱性品红的吸附;对于40 mg/L的碱性品红溶液,当海藻酸纤维的加入量为5 g/L,室温下振荡40 min既能达到吸附平衡,脱色率可达96%;Freundlich等温方程能很好地描述海藻酸纤维对碱性品红的吸附,其吸附行为是物理吸附,吸附过程为熵减过程;海藻酸纤维经过8次再生后,对碱性品红的脱色率仍可达到93%以上,可重复利用。 相似文献
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淀粉与丙烯酰胺的接枝共聚 总被引:6,自引:0,他引:6
本文研究了在硝酸铈铵作用下,淀粉和丙烯酰胺接枝共聚合的反应规律,探讨了引发剂浓度、单体浓度、pH值、反应时间和反应温度对接枝聚合的影响,并对不同的引发体系引发淀粉—丙烯酰胺接枝聚合进行了比较,结果表明,以硝酸铈铵引发的淀粉—丙烯酰胺接枝聚合所产生的均聚物少,引发效率高。 相似文献
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淀粉-丙烯酰胺接枝共聚物的研究进展 总被引:4,自引:0,他引:4
淀粉-丙烯酰胺接枝共聚物具有价廉,无毒,高效,可生物降解等优点,近年来得到了研究者的广泛重视。本文对淀粉-丙烯酰胺接枝共聚物的研究进展进行了综述。 相似文献
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The casein‐acrylonitrile graft copolymer fiber was treated in sodium hydroxide, sodium carbonate, and sodium bicarbonate solutions to evaluate its alkali resistance which was very important for wet processing. The weight loss and whiteness of the treated fibers were examined. UV spectra of the alkaline treatment solutions and IR spectra of the treated fibers were analyzed. The study showed that the fiber exhibited poor alkali resistance. Treating temperature, alkali concentration, and strength affected the weight loss and whiteness of the treated fibers. A high weight loss was found even at low alkali concentration, and the obvious yellowing was observed at higher alkali concentration and temperature. The weight loss was primarily due to the hydrolysis of casein, whereas the yellowing was caused by the hydrolysis of nitrile groups and induced formation of C?N conjugated system. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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接枝法亲水改性腈纶的研究 总被引:2,自引:2,他引:0
采用两步法接枝共聚改性工艺实现腈纶织物亲水改性。通过探索溶胀剂、乳化剂、引发剂的种类和用量,以及活化预处理接枝共聚反应的工艺,确定接枝改性的最佳条件。结果表明:在溶胀剂氯苯7.0g/L, 乳化剂壬基酚聚氧乙烯醚(OP)2.1g/L,引发剂过氧化二苯甲酰(BPO)2.5g/L,亲水性酰胺类单体质量分数 2.0%,活化预处理温度75℃,活化时间30 min,接枝共聚反应温度85℃,反应时间60min,再经浓度为2.0g/ L碳酸钠溶液处理,腈纶织物的吸湿率达到7.0%。 相似文献
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Graft copolymerization of acrylamide onto polyethylene terephthalate (PET) using a CO2 pulsed laser was performed to improve water wettability. After laser irradiation in air, the films were placed in the aqueous solution of monomer and then heated to decompose peroxides formed onto the irradiated PET film. Peroxide density was determined spectrophotometrically by means of the iodide method. The grafted PET surfaces were characterized by attenuated total reflectance infrared spectroscopy, scanning electron microscopy, and contact angle measurements. The electron micrographs showed that the grafting changed the surface morphology of the PET film, which is consistent with the infrared spectra of the grafted films. To evaluate the surface hydrophilicity, water drop contact angle was determined. The contact angle decreased as a result of graft polymerization. It was also found that the hydrophilicity is related to the surface morphology and grafting level. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 401–407, 2000 相似文献
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以混有无机粉体成孔剂的聚对苯二甲酸乙二醇酯(PET)为皮层组分,添加一定量的防蚊剂的聚丙烯(PP)为芯层组分,皮芯质量比为5∶5,通过复合纺丝法纺制PET/PP皮芯复合防蚊纤维;采用氢氧化钠溶液对纤维进行处理,通过正交实验探讨了不同碱处理条件对PET/PP皮芯复合防蚊纤维减量率的影响;对不同减量率下PET/PP皮芯复合防蚊纤维的表面形态、力学性能及防蚊剂保有量进行表征。结果表明:碱液浓度对PET/PP皮芯复合纤维的减量率及皮层PET的成孔影响最为显著;碱处理温度100℃、反应时间60min、碱液质量分数3%,浴比1∶50,减量率达到22.31%,PET/PP皮芯复合纤维的皮层刻蚀程度最大;随着PET/PP皮芯复合纤维减量率的加大,纤维表面孔洞数量、尺寸及密集程度均有所增大,纤维的断裂强度、断裂伸长率和防蚊剂含量明显降低;在碱处理温度100℃,反应时间30 min,碱液质量分数4%条件下处理得到减量率为16.57%的纤维,在烘箱中40℃条件下放置35 d,防蚊剂平均每天释放率为0.01%,减量率为18%的防蚁纤维针织物、对白纹伊蚊的驱避率为95.92%,具有极强的防蚊效果。 相似文献
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黄原胶与丙烯酰胺接枝共聚反应的研究 总被引:1,自引:0,他引:1
以过硫酸铵为引发剂,在氮气保护下,研究了黄原胶与丙烯酰胺的接枝共聚反应。考察了单体浓度、引发剂浓度、反应温度和反应时间等因素对接枝率及接枝效率的影响,探讨了过硫酸铵引发黄原胶接枝丙烯酰胺共聚反应的基本规律。采用红外光谱、X射线粉末衍射对接枝共聚物的结构进行研究,用热重分析法表征了产物的热性能,并初步探讨了接枝机理。结果表明,过硫酸铵能有效地引发黄原胶与丙烯酰胺的接枝共聚反应,并且接枝率和接枝效率随单体浓度、引发剂浓度、反应温度的变化出现极大值,随反应时间的延长不断上升,直至基本不变。 相似文献
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玉米淀粉/丙烯酰胺接枝型高吸水性树脂的合成 总被引:8,自引:1,他引:8
本文以硝酸铈铵为引发剂 ,研究了单体浓度、引发剂浓度、反应温度和反应时间等因素对玉米淀粉与丙烯酰胺接枝共聚制备高吸水性树脂的影响 ,通过反应条件和正交试验 ,确定了最适宜的反应条件和工艺路线 ,制备出了吸水率在 4 5 0~ 70 0g·g-1的玉米淀粉接枝型高吸水性树脂。 相似文献
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Synthesis and characterization of Na‐alginate/acrylamide hydrogel and its application in dye removal
Sodium‐alginate/acrylamide (Na‐alginate/AAm) cross‐linked hydrogel was prepared by using gamma irradiation. The gel content and the water absorbency behavior of the obtained hydrogel were investigated. The thermal and morphological properties of the prepared hydrogel were studied using thermogravimetric analysis and scanning electron microscopy. The thermal stability of Na‐alginate significantly changed when mixed with AAm. The adsorption of basic violet 7 dye on the prepared hydrogel was studied under different experimental conditions. The adsorption process for the basic dye was proven pH dependent. The maximum amount adsorbed (mg/g) of the Na‐alginate/AAm for the dye was found to be 78.1.0 mg/g at pH 9.0. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献