球磨改性稻秆复合高吸水树脂的工艺优化

为了降低高吸水树脂的生产成本和提高水稻秸秆的高附加值综合利用水平,以稻秆为原材料制备高吸水树脂。稻秆先经过球磨处理,然后在水溶液中与单体丙烯酰胺(AM)、丙烯酸(AA)进行接枝共聚反应,制备复合改性高吸水树脂;探讨各反应物的量和反应条件对吸水率和吸盐率的影响,采用二次回归正交法优化了工艺条件。结果表明,球磨处理提高了水稻秸秆吸水树脂的性能;结合单因素试验和响应面优化模型确定球磨改性稻秆高吸水树脂的工艺参数为:交联剂0.058 g,引发剂0.20 g,丙烯酸中和度69%。在此最优条件下,球磨改性水稻秸秆制备的高吸水树脂的吸水率为305.26 g/g,吸盐率为41.58 g/g。     

淀粉预处理对反相乳液法合成高吸水树脂的影响

分别以热糊化(HGL)和机械活化(MAC)木薯淀粉(st)为母体,丙烯酸(AA)为反应单体,通过反相乳液聚合制备淀粉接枝丙烯酸高吸水树脂。考察了AA/st质量比、引发剂(APS)用量、交联剂(MBIS)用量对淀粉基高吸水树脂吸液能力的影响,并利用红外光谱仪对产品结构进行表征。结果表明,AA单体成功接枝于st上,AA/st质量比、APS用量和MBIS用量是影响树脂吸液能力的主要因素。机械活化淀粉接枝丙烯酸高吸水树脂(MAC-st//AA)与热糊化淀粉接枝丙烯酸高吸水树脂(HGL-st/AA)相比,APS用量和MBIS用量大大降低,最大吸去离子水倍率增加194.51 g/g,提高了43.14%,最大吸生理盐水倍率增加16.88g/g,提高了27.1%。由此表明,机械活化预处理技术较热糊化预处理技术对反相乳液法制备淀粉基高吸水树脂可以降低原料用量,减少成本。     

亚麻废纱制备的纤维素基高吸水保水树脂及其性能

为了解决目前麻纺工业废料后续处理及环境污染问题,以麻纺企业废弃的亚麻纱线为原料,进行化学脱胶获取纤维素,采用非均相聚合体系,以纤维素为基质接枝丙烯酸单体制备高吸水保水树脂。采用单因素实验针对制备体系的工艺条件进行优化,并对较优条件下制备的纤维素基高吸水保水树脂进行性能表征。结果表明：最优合成工艺为单体丙烯酸、引发剂过硫酸铵、交联剂N, N’-亚甲基双丙烯酰胺用量分别为5、0.1、0.04 g/g纤维素,反应温度70℃,反应时间3 h;合成高吸水保水树脂在去离子水、自来水和0.9 wt%盐水中吸水倍率分别为658 g/g、382 g/g和65 g/g;室温（25℃）下自然风干12 d,保水率为74.3 %,鼓风干燥箱内30℃放置10 h,保水率为81.2 %,60 ℃放置10 h,保水率为26.4 %。说明制备的亚麻纤维素基高吸水保水树脂具有良好的吸水保水性能,可广泛应用于在农林、园艺等实际生产领域。     

桉木浆CLS-AA-SPS互穿网络型高吸水树脂的制备研究

桉木浆品质好、纤维素含量高是一种优良的天然纤维素来源。利用桉木纤维素制备可生物降解的高吸水树脂可提升桉木纸浆的经济附加值,拓展桉木纸浆的应用领域。纤维素系吸水树脂产品耐盐性好、pH易调节,易于生物降解、无毒性残留,不会成为新的环境污染源,使用范围日益广泛,成为近年来研究的热点。本论文使用酶预处理桉木浆,再经NaOH/尿素溶液低温预处理,与丙烯酸(AA)及聚乙烯醇硫酸钠(SPS)反应,通过接枝共聚制备具有互穿网络结构的吸水倍率高、耐盐性好的纤维素-丙烯酸-聚乙烯醇硫酸钠(CLS-AA-SPS)高吸水树脂。通过单因素试验,运用Minitab软件和Box-Behnken实验设计对影响接枝共聚的主要影响因子SPS用量(X_1)、交联温度(X_2)、丙烯酸中和度(X_3)的最佳条件进行了优化,得到该响应值的多元回归二次拟合模型为:Y=-50338.00+3781.50X_1+1070.73X_2+647.59X_3-3216.67X_1~2-9.07X_2~2-6.17X_3~2+X_1X_2+0.50X_1X_3+0.54X_2X_3。优化后的反应条件为,SPS加入量为丙烯酸单体质量的2%,交联温度60.1℃,中和度55.2%。制备的吸水树脂的吸水倍率为1126g/g,吸生理盐水倍率为143.2g/g,吸尿液倍率为83.9g/g,与纤维素-丙烯酸(CLS-AA)吸水树脂相比,其吸水倍率提高128g/g,吸生理盐水倍率提高24g/g,吸人工尿液倍率提高了15g/g。桉木浆、CLS-AA吸水树脂和CLS-AA-SPS吸水树脂的热稳定分析的最后残留灰分达到了13%,22.3%和30.2%,CLS-AA-SPS互穿网络型树脂具有更好的热稳定性。红外图谱、扫描电镜和热重定分析结果均表明,合成的桉木浆CLS-AA-SPS互穿网络吸水树脂存在互穿网络结构。     

柚子皮纤维素基高吸水性树脂的合成与应用

高吸水树脂因其优良的吸水性和保水性,近年来受到广泛关注与研究。为实现柚子皮的废物利用,优化高吸水树脂的生产工艺,研究以天然无毒的柚子皮粉为接枝骨架,丙烯酸为接枝单体,司班-80为分散剂,环己烷为油相,过硫酸钾为引发剂,N,N’-亚甲基双丙烯酰胺为交联剂,采用反相悬浮聚合法制备了吸水性和吸生理盐水性能良好的纤维素基高吸水树脂。探讨了司班-80用量、引发剂用量、柚皮粉用量、交联剂用量、丙烯酸中和度、反应温度、油水质量比对树脂在蒸馏水和生理盐水中的吸液倍率的影响。结果表明,在司班-80用量为单体的6.7%,引发剂用量为单体的0.5%,柚皮粉:丙烯酸为1:5,交联剂为单体的0.67%,丙烯酸中和度40%,油水比2:1,反应温度80℃条件下,树脂对蒸馏水和生理盐水最大吸液倍率可达362.29 g/g和42.49 g/g。     

响应面优化微波法制备芭蕉芋淀粉接枝丙烯酸高吸水性树脂工艺

研究响应曲面优化微波法制备芭蕉芋淀粉接枝丙烯酸高吸水性树脂的工艺。在单因素试验的基础上,采用响应曲面法研究单体用量、引发剂用量和单体中和度对树脂吸水倍率的影响,并对共聚物结构进行分析。结果表明,微波法制备芭蕉芋淀粉接枝丙烯酸高吸水性树脂的最佳工艺为单体丙烯酸与干淀粉比8.2:1(mL/g)、引发剂用量为干淀粉质量的2.8%、单体丙烯酸中和度80.1%时,此时树脂的吸水倍率为769g/g。红外扫描吸收谱表明,接枝共聚物中存在着羧基、酰胺基等特征性亲水性基团。     

聚乙烯醇/纳米微纤丝涂布增强砂纸原纸性能研究

研究了聚乙烯醇(PVA)/纳米微纤丝(NFC)涂布对砂纸原纸防油性能及力学性能的影响。研究结果表明:PVA浓度5%涂布的砂纸原纸各项性能均弱于PVA10%浓度的涂布纸。5%PVA涂布(涂布量为2.61g/m~2)时,随着NFC用量增加,其防油性能得到了相应提高,但其防油等级均在6以下;10%PVA涂布(涂布量为8.27g/m~2)时,其涂布后砂纸原纸防油等级均在12左右。在PVA浓度为5%时,涂布纸的拉伸强度比砂纸原纸的提高了约100%;在相同5%NFC的添加量下,10%PVA涂布纸的拉伸强度比5%的提高了约67.37%。随着NFC添加量的增加,纸张的耐折度随之提升。当NFC的添加量在合适范围内,纸张的撕裂度也随NFC添加量的增加而提高。     

响应面分析法优化高吸水树脂涂布纸涂布工艺的研究

通过响应面设计分析方法,对高吸水涂布纸的表面涂布工艺进行了系统研究。探究了涂布液固含量(X_1)、聚乙烯醇配比(X_2)、高吸水树脂粒径(X_3)、涂布量(X_4)对涂布纸张的吸液量和Cobb(60)吸水值等指标的影响,并拟合了四个因素对目标指标的二次多项式回归方程。交互项分析结果为:四因素对吸液量的交互影响不显著; X1X4交互项对Cobb(60)、耐破指数和透气度影响均最大; X1X2交互项对抗张指数的影响最大。最佳涂布工艺条件为:涂布液固含量为5. 0 wt%,PVA配比为5. 0%,高吸水树脂粒径为100～120目的颗粒,涂布量为5. 0 g/m~2,制备得到的涂布吸水纸的吸液量为3. 00 g/g,Cobb(60)吸水值为326. 65 g/m2,耐破指数为1. 70 k Pa·m~2/g,抗张指数为10. 83 N·m/g,透气度为16. 47μm/(Pa·s)。     

马铃薯淀粉复合吸水树脂合成工艺优化

选用马铃薯淀粉和高岭土、丙烯酸、丙烯酰胺为原料,以水溶液聚合法进行接枝共聚复合型吸水树脂合成的研究,并利用均匀设计法对合成工艺进行优化.优化后的合成条件是:当引发剂2 mL;交联荆1 mL;单体配比4:4(W:W);马铃薯淀粉2 g;反应温度65℃;反应时间2 h.制备的复合高吸水树脂吸蒸馏水可达960 g/g左右.     

淀粉系列高吸水树脂的研究概况

高吸水性树脂是一种新型的功能高分子材料,由含强亲水性基团的单体经过适度交联使其能够吸收上百倍甚至上千倍的水。本文从吸水机理、聚合方法、影响因素及树脂的性能等方面综述了淀粉系列高吸水树脂的研究概况,并且介绍了淀粉接枝共聚高吸水树脂在生理卫生、医疗器械、土木建筑、农业、食品等方面的应用。     

耐盐性糯小麦淀粉树脂的合成与结构分析

以糯小麦淀粉为原料,丙烯酸、丙烯酰胺、丙烯酸甲酯为单体,过硫酸铵为引发剂,N,N’-亚甲基双丙烯酰胺为交联剂,采用接枝共聚法制备耐盐性高吸水性树脂.研究了在氮气保护的情况下,丙烯酸中和度、丙烯酰胺用量、丙烯酸甲酯用量、反应温度,引发剂用量和交联剂用量对高吸水性树脂吸盐水性能的影响.得到的较优工艺条件为:丙烯酸中和度/pH5.8,丙烯酰胺14g,丙烯酸甲酯1mL,反应温度75℃,引发剂4％过硫酸铵溶液5mL,交联剂2％N,N’-亚甲基双丙烯酰胺溶液0.5mL.此条件下制备的高吸水性树脂吸盐水倍率达到62.1g·g-1.     

β-环糊精在纤维素上的固载及其对肉桂醛的包埋与释放

采用聚丙烯酸作为交联剂,将β-环糊精(β-CD)接枝到纤维素并对其工艺特点进行了探讨,然后利用该纤维素对挥发食品抗菌剂肉桂醛进行包埋,并研究了其释放特性。结果表明:聚丙烯酸法能够使β-环糊精固载于纤维素上,当环糊精固载量控制在12%～14%时,肉桂醛包埋量大约在8～9μL/g。肉桂醛在功能纤维素中的释放量随环境相对湿度增加而增大。     

共混改性丙烯酸-丙烯酰胺共聚纤维研究

通过添加有机物或无机物对丙烯酸-丙烯酰胺共聚物进行共混改性,制备具有较好吸水性的丙烯酸-丙烯酰胺共聚纤维,分析和讨论了共混物对纤维形貌、热性能及吸水性能的影响。结果表明:纤维中添加亲水性聚合物聚乙烯醇后,玻璃化温度降低,纤维的柔韧性得到改善;纤维中添加海泡石后,其吸水速率和平衡吸水率均得到提高。     

交联剂对魔芋超强吸水剂凝胶强度和吸水倍率的影响

以魔芋葡甘聚糖为基体,丙烯酸为单体,过硫酸钾为引发剂,分别以N,N’-亚甲基双丙烯酰胺(MBA)、甘油、聚乙二醇600(PEG600)、Ca(NO3)2.4H2O为交联剂,制备魔芋超强吸水树脂(KSAP),测试其凝胶强度和吸水倍率,同时对其进行红外光谱结构表征。实验表明,以MBA为交联剂制得的KSAP的凝胶强度最大,可达到153.7g/cm2,以甘油为交联剂制得的KSAP的吸水倍率最高,可达1201g/g。     

反相悬浮聚合法制备相变蓄冷材料及其应用

为提升吸水树脂（superabsorbent resin, SAR）的吸水能力,增加其用作蓄冷材料的潜热,采用了单因素实验结合Box-Behnken试验的方法,将反相悬浮聚合法制备SAR的条件进行了优化,并通过双孢菇的贮藏实验表明了其蓄冷效果。结果表明:制备SAR的最优反应条件为:交联剂为单体丙烯酸（AA）质量的0.06%,引发剂0.9%,分散剂4.38%,淀粉10%,中和度75%,反应单体AMPS:AA为1:10,反应温度65 ℃,产物单位吸水量为573.26 g/g;吸水量的增加提升了制备蓄冷材料在保温箱中保持环境低温的能力,可以在12 h内基本保持10 ℃以下的低温环境,而且在25 ℃条件下,可以更好地保持双孢菇色泽,抑制失重、刺激气味的产生和质构的变化,表明通过优化SAR吸水性对其蓄冷性能的提升可以更好地保持双孢菇贮藏品质。     

Bioscouring and bleaching process of cotton fabrics – an opportunity of saving water and energy

Bio-processing was accompanied by a significant lower demand of energy, water, chemicals, time and costs. This study attempted to introduce the bio-processes in the conventional scouring and bleaching with peracetic acid (PAA) of the cotton fabrics. The scouring with two types of pectinases, acting under acidic and alkaline conditions, respectively, was as efficient as the chemical process in terms of obtained adequate water absorbency of the fabrics. Bleaching with PAA can substitute bleaching with hydrogen peroxide when medium degree of whiteness is demanded. The bioscouring and bleaching with PAA processes cause no damage to fibres and this is one of the benefits of such processes. Wastewaters are not charged with harmful chemicals. The consumption of water and energy is the lowest at combined scouring/bleaching treatments. Consequently, at these processes arises the lowest amount of effluents and the produced wastewater is biodegradable.     

Synthesis and Investigation of Swelling Behavior of Grafted Alginate/Alumina Superabsorbent Composite

In this study a novel alginate‐g‐poly(acrylic acid)/alumina composite was synthesized and characterized. Preparation of the composite hydrogels involved free radical polymerization of a combination of alginate, acrylic acid (AA) and distilled water, in appropriate amounts and N,N‐methylene bisacrylamide (MBA) as crosslinking agent. The composite formation was confirmed by Fourier transform infrared spectroscopic (FT‐IR). The surface morphologies of the synthesized hydrogels were assessed by scanning electron microscopy. Systematically, the different variables of the graft copolymerization were optimized to achieve maximum swelling capacity. The swelling of superabsorbent hydrogels was measured in various solutions with pH values ranging from 0 to 14. In addition, the pH reversibility, on–off switching behavior, swelling kinetics in distilled water and the absorbency under load (AUL) were investigated.     

Fast‐swelling Superabsorbent Hydrogels from Poly(2‐hydroxy ethyl acrylate‐co‐sodium acrylate) Grafted on Starch

Fast‐swelling highly porous superabsorbent hydrogels were synthesized through a rapid radical polymerization under normal atmospheric conditions. To synthesize a biopolymer‐based superabsorbent hydrogel, 2‐hydroxyethyl acrylate (HEA) and sodium acrylate (AANa) were grafted on the starch backbone in an aqueous solution. The graft copolymerization reaction was carried out in the presence of ammonium persulfate (APS) as an initiator and ‐methylenebisacrylamide (MBA) as a crosslinker in a homogeneous medium. The chemical structure of the hydrogels was confirmed by FT‐IR spectroscopy and thermogravimetric analysis (TGA). The morphology of the samples was examined by scanning electron microscopy (SEM). The results indicated that with increasing the amount of sodium acrylate both swelling capacity and swelling under load (AUL) were increased. Preliminary swelling and deswelling behaviors of the hydrogels were also studied. The effects of pH and inorganic salt on the swelling behavior of the hydrogels were investigated as well.     

Enzymatic scouring and bleaching of cotton terry fabrics – opportunity of the improvement on some physicochemical and mechanical properties of the fabrics

In the present study, an attempt was made to treat cotton terry fabrics with alkaline pectinase enzyme and observe the effects on the properties including the degree of whiteness, water absorbency, pill formation, weight loss after abrasion, tenacity at maximum load, degree of polymerization (DP), and hand feeling of the fabric. The enzymatic treatment of cotton terry fabrics had a positive influence on some of their properties. The degree of damage of cotton terry fabrics after 20 washings in a domestic washing machine was determined by analyzing the tenacity at maximum load, weight loss after abrasion, fabric hand feeling, and the DP. Enzymatic-scoured fabrics had a higher resistance to abrasion, a lower decrease in the DP, and a higher rating of the fabric hand feeling compared with alkaline-scoured fabrics. Enzymatic processing was accompanied by a significant lower demand of energy and water. Consequently, at these processes arises the lowest amount of effluents and the produced wastewater is biodegradable. This study attempted to introduce enzymatic scouring (ES) and bleaching with peracetic acid (PAA) of the cotton terry fabrics.