聚丙烯酸钠高吸水性树脂的改性研究进展

从提高聚丙烯酸钠高吸水性树脂的凝胶强度以及耐盐性和稳定性、改善降解性能、控制吸水速度等方面,对聚丙烯酸钠高吸水性树脂的改性方法进行了综述,提出改性工艺研究和改性原理研究、实现高功能化聚丙烯酸钠高吸水性树脂的分子水平设计,是聚丙烯酸钠高吸水性树脂改性研究的重要方向。     

改性吸水树脂合成及其吸水膨胀橡胶的性能

本文以聚丙烯酸钠为主要原料,用抗坏血酸/过氧化氢为引发体系合成了聚丙烯酸钠系吸水树脂,并将所制备的吸水树脂与天然橡胶制备成吸水膨胀橡胶,考察了甲基丙烯酸缩水甘油酯（GMA）与丙烯酸钠的比例对吸水树脂性能及其吸水膨胀橡胶性能的影响。实验结果表明, GMA改性吸水树脂对吸水树脂及其吸水膨胀橡胶性能的吸水性能有较大的影响,同时GMA改性吸水树脂可与橡胶共硫化。当GMA的物质量比为2%时,制备的吸水橡胶各项性能最佳,力学性能较佳,橡胶吸水膨胀过程中,吸水树脂析出现象显著降低。     

改性芳纶短纤维和聚丙烯酸钠对丁腈橡胶吸水膨胀橡胶性能的影响

用磷酸刻蚀改性芳纶短纤维,以改性芳纶短纤维作为增强填料制备丁腈橡胶(NBR)吸水膨胀橡胶(炭黑和白炭黑用量均为20份),研究聚丙烯酸钠(吸水树脂)和改性芳纶短纤维用量对NBR吸水膨胀橡胶物理性能和吸水性能的影响。结果表明:聚丙烯酸钠用量对NBR吸水膨胀橡胶的拉伸强度、拉断伸长率、吸水膨胀率和质量损失率影响较大,聚丙烯酸钠的适宜用量为60份;改性芳纶短纤维用量增大,NBR吸水膨胀橡胶的硬度增大,拉伸强度提高,吸水膨胀率和质量损失率减小,改性芳纶短纤维的适宜用量为4份。     

聚丙烯酸/高岭土复合高吸水树脂的制备及结构性能研究

以丙烯酸和高岭土为原料,采用水溶液聚合法制备了聚丙烯酸/高岭土复合高吸水树脂,对其结构性能进行了研究。结果表明:当丙烯酸质量分数为20%,高岭土质量分数为10%,过硫酸钾质量分数为0.13%,N,N'-亚甲基双丙烯酰胺质量分数为0.2%,反应温度为80℃,反应时间为3 h时,所制的聚丙烯酸/高岭土复合高吸水树脂表面形貌良好,高岭土分散均匀,吸水倍率为132 g/g,保水率为93.9%,凝胶形变量为2.3 mm;聚丙烯酸高吸水树脂的吸水倍率为121 g/g,保水率为82.5%,凝胶形变量为7.1 mm;高岭土的加入不仅提高了聚丙烯酸树脂的吸水倍率、吸水速率与保水率,且显著提高了聚丙烯酸树脂的凝胶强度。     

技术贸易

正丙烯酸系高吸水性树脂项目简介高吸水性树脂是一类具有高吸水保水性能的高分子材料,已在医药卫生、农林园艺等领域扮演重要角色。理想的高吸水性树脂应具备高吸水能力、高吸水速率、良好的机械强度;本项目开发的多孔性高吸水性树脂在吸水能力和吸水速率上具有很大优势项目内容主要包括基于聚丙烯酸(钠)-丙烯酰胺高吸水性树脂的生产技术,可获得同时具有高吸水/盐水倍率和速率的簇状多孔高吸水性微球树脂。     

PEGDA交联PAA-K高吸水树脂制备及性能研究

采用紫外引发、微波引发方法分别制备聚丙烯酸钾(PAA-K)高吸水树脂,研究了交联剂聚乙二醇二丙烯酸酯(PEGDA)、光引发剂2,2二甲氧基苯基乙酮(BDK)、引发剂过硫酸铵(APS)以及丙烯酸(AA)中和度对PAA-K高吸水树脂吸水性能的影响以及两种方法制备PAA-K树脂性能的比较。采用傅里叶变换红外光谱仪、热失重分析仪、扫描电子显微镜等仪器对PAA-K高吸水树脂进行表征。结果表明,在最佳优化条件下,紫外引发PAA-K高吸水树脂在蒸馏水和生理盐水中的最大吸水倍率分别为3297 g/g和419 g/g;微波引发PAA-K高吸水树脂在蒸馏水和生理盐水中的最大吸水倍率分别为2861 g/g和414 g/g。     

改性玉米芯生物基/聚丙烯酸钠高吸水树脂的制备及吸水性能

通过对玉米芯依次进行物理和化学改性,加入引发剂亚硫酸氢钠和过硫酸铵(APS)、交联剂N,N'-亚甲基双丙烯酰胺,制备了改性玉米芯生物基/聚丙烯酸钠高吸水树脂.分别考察了w(改性玉米芯)、w(交联剂)、w(引发剂)和反应温度对树脂吸水性能的影响.实验表明,以丙烯酸质量为基数,w(改性玉米芯)=0.15％、w(交联剂)=0...     

辐射悬浮聚合法制备高吸水树脂

介绍了用60 Coγ射线引发丙烯酸钠等单体反相悬浮聚合制备球状高吸水树脂的方法 ,确定了以聚丙烯酸作为悬浮聚合体系稳定剂 ,考察了剂量率、剂量对高吸水树脂的吸液倍数的影响     

高吸水树脂的吸水机理及吸盐性的改进

介绍了高吸水树脂的结构和性能。从热力学角度阐述了高吸水树脂的吸水机理,分析了高吸水树脂吸盐性能的影响因素,总结了改进耐盐性的几种方法。简要介绍了高吸水树脂的发展和应用。     

聚丙烯酸高吸水树脂的合成及性能研究

采用水溶液聚合法,以丙烯酸为单体、N,N,-亚甲基双丙烯酰胺为交联剂、过硫酸钾为引发剂,合成聚丙烯酸高吸水树脂,对合成产物的吸水倍率、保水性能及重复吸水能力进行研究。结果表明,交联剂用量为0.1%、中和度80%、引发剂用量为1.5%时合成的聚丙烯酸树脂具有较高的吸水性能,吸水倍率可达416.72,树脂保水和重复吸水性能良好。     

超吸水材料的研究进展

超吸水材料具有吸水倍数高、保水能力强、外观柔软、内部呈多孔网状结构等优点,但存在对含电解质水溶液吸收能力有限的问题。本文首先分析了超吸水材料的吸附机理,在此基础上着重介绍了超吸水树脂、超吸水纤维、超吸水膜、超吸水织物基气凝胶吸水材料的制备原理与特点,其次概述了不同形式吸水材料对去离子水、盐水、合成尿、尿素的吸附机理差异,指出增加吸水材料的比表面积、亲水基团数量、分子量,适当的交联度和中和度,并结合高的渗透压、静电排斥力、额外添加无机粒子可提高吸液能力,随后简述了高分子气凝胶与纺织品相结合构筑超吸水织物在安全防护领域的应用情况,最后对超吸水材料的可增长点进行了展望,以期为提高超吸水材料对含电解质水溶液的吸收能力提供理论参考和技术支持。     

高吸水树脂结构与性能的关系及结构表征方法研究进展

首先系统综述了高吸水树脂的结构与吸水性能关系的研究进展和高吸水树脂结构表征手段的开发进展,指出了当前在结构与性能关系方面研究的不足和表征方法的局限性,并对其原因进行了分析.然后就深入研究高吸水树脂结构与性能关系提出了设想和思路。     

Adsorption of anionic dyes on a reversibly swelling cationic superabsorbent polymer

A cationic monomer [2‐(methacryloyloxy)ethyl]trimethylammonium chloride was polymerized using N,N′‐methylenebisacrylamide as the crosslinker to obtain a cationic superabsorbent polymer (SAP). This SAP was characterized by Fourier transform‐infrared spectroscopy, and the equilibrium swelling capacity was determined by swelling in water. The SAP was subjected to cyclic swelling/deswelling in water and NaCl solution. The conductivity of the swelling medium was monitored during the swelling/deswelling and was related to the swelling/deswelling characteristics of the SAP. The adsorption of five anionic dyes of different classes on the SAP was carried out and was found to follow the first‐order kinetics. The Langmuir adsorption isotherms were found to fit the equilibrium adsorption data. The dye adsorption capacity of the SAP synthesized in this study was higher than that obtained for other hydrogels reported in the literature. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Effective removal of a cobalt‐tetrasulfonated phthalocyanine dye from an aqueous solution with a novel modified chitosan‐based superabsorbent hydrogel

Industrial wastewaters from the Merox process are heavily polluted by toxic cobalt‐tetrasulfonated phthalocyanine (CoTsPc) dye catalyst, and in this article, we describe the synthesis of novel chitosan hydrogels and their adsorption capabilities against CoTsPc as biosorbents. In this study, novel chitosan hydrogels were crosslinked by 3,3′,4,4′‐tetracarboxybenzophenone dianhydride and used for the first time. The adsorption capacities of the hydrogels were significantly improved, and they exhibited excellent sorption behavior with ammonium sulfate modification. The adsorption behavior was observed to be pH dependent, and the optimum pH was found to be 8. Moreover, the swelling studies indicated that the hydrogels are superabsorbent. The reusability of these dye‐adsorbent hydrogels was also evaluated. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46167.     

VMT/P(AMPS-co-AA)复合高吸水树脂的性能测试

研究了溶液pH、盐浓度对辉光放电电解等离子体引发合成的蛭石/聚(2-丙烯酰胺-2-甲基丙磺酸-co-丙烯酸) (VMT/P(AMPS-co-AA)) 复合高吸水树脂的溶胀行为的影响,考察了染料pH、吸附时间、染料浓度等因素对复合高吸水树脂吸附量的影响,同时对树脂的吸附-解吸性能进行了研究。结果表明, VMT/P(AMPS-co-AA)具有高吸水性、pH敏感性、盐敏感性以及高吸附性。该树脂在蒸馏水中的最大溶胀率达到822.4 g/g,对阳离子染料亚甲基蓝(MB)、结晶紫(CV)和孔雀石绿(MG)的吸附量分别可达2027.8, 2171.8和883.2 mg/g。在pH=6.5和25℃下,其对染料的吸附行为符合动力学准二级模型,该树脂还具有一定的吸附-解吸性能和重复利用性能。     

Study on plasma-modified corn stover-humic acid-based superabsorbent resin

This research aimed to prepare superabsorbent resin from agro-mining waste, which is important for sustainable development and practical application in agriculture and forestry. Corn stover (CS), humic acid (HA), acrylic acid (AA), and acrylamide (AM) were used as raw materials to produce CS–HA-based superabsorbent resin (p-CS-HA-PAA) by plasma modification, and the optimum modification conditions were obtained. The superabsorbent resin was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and contact angle analysis. The adsorption characteristics of the superabsorbent resin were analyzed by kinetic model fitting, and the performances were tested. The results showed that the water absorption capacity could reach 1106.9 g/g under the following optimal process conditions: a discharge time of 180 s, a discharge power of 40 W, and a discharge pressure of 20 Pa. The characterization confirmed that plasma modification could make the surface of the superabsorbent resin rougher, produce more and larger pores, and introduce more hydrophilic groups. The p-CS-HA-PAA conformed to the pseudo-second-order kinetic equation and non-Fickian intradiffusion process in aqueous solution. The chemical resistance, repeated liquid absorption, and water retention properties of the modified resin were better than those of the unmodified resin, which provided a viable way for industrial and agricultural applications.     

高吸水性树脂研究进展

介绍了高吸水性树脂的种类,回顾了国内外高吸水性树脂的发展历程,论述了高吸水性树脂的结构及吸水机理阐,述了高吸水性树脂的制备方法及应用领域展,望了高吸水性树脂的发展方向。     

多孔高吸水性树脂孔结构的图像分析法

本文探索了一种对多孔高吸水性树脂的孔结构进行定量表征的研究方法。采用Image J图象处理软件,将多孔高吸水性树脂的SEM照片转换为二值图后,利用软件的图形处理与计算功能,结合体视学的原理,得到多孔高吸水性树脂的孔结构参数。根据差分盒维数的思想,结合MATLAB编程计算,对二值图处理后得到图象的分形维数,用以表征结构复杂的多孔高吸水性树脂孔结构的规整性。通过所建立的表征方法,对不同预溶胀时间下通过冷冻诱导相分离法制备的多孔高吸水性树脂的结构的变化规律进行了讨论。     

Preparation and adsorption properties of a novel superabsorbent based on multiwalled carbon nanotubes–xylan composite and poly(methacrylic acid) for methylene blue from aqueous solution

A novel superabsorbent was prepared by the copolymerization reaction between multiwalled carbon nanotubes (MWCNTs)–xylan composite and poly(methacrylic acid) (PMAA) in the presence of N,N′‐methylenebisacrylamide as cross‐linker and the redox initiation system (NH)₄S₂O₈‐anhydrous Na₂SO₃ as initiator for adsorbing methylene blue (MB) from aqueous solution. First, covalent modification of MWCNTs with a natural polymer xylan was achieved by the nucleophilic substitution reaction. The obtained xylan modified MWCNTs–xylan composite was characterized by transmission electron microscope, Fourier transform infrared spectroscopy, X‐ray photoelectron spectrometer, and thermal gravimetric analysis. The results indicated that the hydroxyl groups of xylan participated in the formation of MWCNTs–xylan composite, and MWCNTs–xylan composite contained 32% xylan and about four molecule chains of xylan were grafted onto 5,000 carbon atoms of MWCNTs sidewalls. Subsequently, a novel superabsorbent based on MWCNTs–xylan composite and PMAA was prepared and characterized by Fourier transform infrared spectroscopy, scanning electron microscope, and swelling test. The results proved that superabsorbent was successfully prepared by copolymerization reaction and found that the superabsorbent evidently presented three‐dimensional network structure. Swelling process of superabsorbent complied with the Fick's law. Adsorption property of superabsorbent for MB was also systematically studied by investigating these parameters, such as superabsorbent dosage, initial MB concentration, contact time, ion strength, and pH. The superabsorbent presented a higher adsorption capacity and removal rate for MB. The adsorption data were fitted by Langmuir, Freundlich isotherm models, and four adsorption kinetic models. Freundlich isotherm model better fitted the equilibrium data than Langmuir, and adsorption kinetics could be well described by pseudo‐second‐order kinetic and intraparticle diffusion. These results indicated that the superabsorbent can be used as an efficient absorbent for removal of MB from aqueous solution. POLYM. COMPOS., 35:1516–1528, 2014. © 2013 Society of Plastics Engineers     

Synthesis of crosslinked superabsorbent carboxymethyl cellulose/acrylamide hydrogels through electron‐beam irradiation

A study on the possibility of the preparation of superabsorbent hydrogels based on crosslinked carboxymethyl cellulose polymer and acrylamide monomer through electron‐beam irradiation was carried out. The effects of the irradiation dose and polymer–monomer compositions on the crosslinking density were studied. The hydrophilic properties of the superabsorbent hydrogels were identified by the swelling percentage. The prepared hydrogels had higher swelling in distilled water than in salt solutions. Moreover, the hydrogels exhibited the highest swelling at pH 7. Also, increasing the temperature up to 50°C caused an increase in the swelling. The thermal properties of the hydrogels were characterized with thermogravimetric analysis. The use of the prepared superabsorbent hydrogels for the growth of rice was also investigated through the water‐retention property. The water retention in the soil was enhanced with the hydrogels. Superabsorbent hydrogels based on carboxymethyl cellulose polymer and acrylamide monomer could be considered as water‐managing materials for agriculture and horticulture in desert and drought‐prone areas. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2003–2008, 2007