GG-g-PAA／SH高吸水性树脂的制备与缓释性能研究

以天然瓜尔胶（GG）、丙烯酸（AA）和腐植酸钠（SH）为原料,过硫酸铵为引发剂,N,N’-亚甲基双丙烯酰胺为交联剂,采用水溶液聚合法制备了环境友好的多功能瓜尔胶接枝聚丙烯酸／腐植酸钠（GG-g—PAA／SH）高吸水性树脂。考察了腐植酸钠含量对树脂吸水性能的影响,评价了树脂在沙土中的实际保水性能、反复溶胀性能和腐植酸钠肥料缓释性能。结果表明,在体系中引入廉价的腐植酸钠,不但降低生产成本,还能提高树脂的吸水能力,当腐植酸钠含量为15wt％时,高吸水性树脂吸蒸馏水和生理盐水的倍率分别为532g／g和62g／g。在沙土中加入高吸水性树脂能显著提高其保水性能,30d后仍能保持13％的水分。此外,GG-g-PAA／SH高吸水性树脂还具有较优的反复溶胀性能和腐植酸钠肥料缓释功能,可用作兼具吸水、保水和缓释性能的新型节水材料。     

改善高吸水性树脂性能的方法

简述了高吸水性树脂的吸水机理、在耐盐性、吸水速度、吸水强度和使用寿命4个方面介绍了改善高吸水性树脂性能的方法，最后指出今后高吸水性树脂的研究方向。     

我国高吸水性树脂的制备及性能研究进展

介绍了我国近20年来高吸水性树脂的研究情况。     

凹凸棒黏土纯度对复合高吸水性树脂吸水性能的影响

将凹凸棒黏土分级处理后,以不同纯度的凹凸棒黏土为无机组分,过硫酸铵为引发剂,N,N'-亚甲基双丙烯酰胺为交联剂,制备了羧甲基纤维素接枝丙烯酸/凹凸棒黏土复合高吸水性树脂,考察了复合高吸水性树脂的吸水倍率、吸水速率和在不同pH介质中的溶胀性能。红外光谱表明,丙烯酸已接枝到羧甲基纤维素的骨架上,凹凸棒黏土参与了聚合反应。扫描电镜观察表明,凹凸棒黏土在高吸水性树脂中有良好的分散性能,改善了基体表面的多孔结构。研究表明,在相同添加量下,凹凸棒黏土中含有更多的Ca2+和Mg2+离子,有助于改善复合高吸水性树脂的综合性能。     

黄原胶/膨润土复合高吸水性树脂的制备与性能研究

采用水溶液聚合法制备了黄原胶(XG)/膨润土有机-无机复合SAP(高吸水性树脂)。通过单因素试验法和正交试验法优选出制备复合SAP的最佳工艺条件。结果表明:丙烯酸(AA)、丙烯酰胺(AM)、XG与膨润土之间发生了接枝共聚反应;当m(AA)∶m(AM)=5∶1、AA中和度为75%、w(膨润土)=5%、w(引发剂)=1.0%和w(交联剂)=0.08%时,相应的复合SAP具有最大的吸水倍率(863.8 g/g)和吸盐水倍率(109.4 g/g)。     

高吸水性树脂的制备及结构性能的研究进展

高吸水性树脂是一种新型功能高分子材料，具有优异的性能和广泛的用途。本文简述了高吸水性树脂的制备，探讨高分子结构，Flory理论及溶液热力学理论与吸水机理的关系，并讨论高吸水性树脂的应用及其在高性能化，可降解性，复合化等方面的研究进展。     

我国高吸水性树脂的制备及性能研究进展

介绍了我国近 2 0年来高吸水性树脂的研究情况。     

高吸水性树脂的制备及交联剂对树脂吸水性能的影响

用反相悬浮聚合和滴加单体的方法制备以聚乙二醇双丙烯酸酯交联的聚丙烯酸钠高吸水性树脂。详细探讨了温度,引发剂和单体浓度,油水比等最佳反应条件。     

高吸水性树脂与纤维

近年来世界高吸水性树脂发展很快,现全球的需求量已达６０万－７０万ｔ／ａ,今后将以７％－８％之速度增长,因此有关生产厂家在不断提高产能,其中日本触媒集团的总产能到２００１年达到２３万ｔ／ａ,保持世界最大的生产厂家的地位。在高吸水性纤维方向,以加拿大和钟纺合纤公司发展最快,目前其纺织丝和无纺布等加工口的年产能力各为４０００ｔ和２０００ｔ,预期３年后各将扩大到１．４万ｔ／ａ和３５００ｔ／ａ,主要用作无纺     

SLs-AA型高吸水性树脂的应用性能研究

制备SLs-AA型高吸水性树脂,研究了外部溶液中离子种类与浓度及不同pH值的溶液对该树脂吸水倍率的影响,分析不同粒径吸水性该树脂的吸水倍率随时间的变化和该树脂在土壤中的抑制蒸发情况,并在分析过程中讨论SLs-AA型高吸水性树脂吸水机理。     

淀粉-丙烯酸/聚丙烯酰胺复合吸水树脂的制备及性能

淀粉用环氧氯丙烷进行预交联,与丙烯酸接枝共聚,生成淀粉-丙烯酸共聚物;再与聚丙烯酰胺聚合,制备淀粉-丙烯酸/聚丙烯酰胺复合高吸水树脂。考察了淀粉用量、引发剂及交联剂对吸水倍率的影响。结果表明,当淀粉用量取2.5 g,复合引发剂取0.02 mmol,交联剂取0.1%时,吸水倍率最大;吸水速率20 min内达到吸水溶胀平衡。     

Synthesis and Characterization of Poly(acrylic acid)/modified Bentonite Superabsorbent Polymer

A novel poly(acrylic acid)/modified bentonite superabsorbent polymer (SAP) was synthesized through chemical crosslinking by a polymerization technique in a complete aqueous environment. This SAP was fabricated effectively by dispersing modified bentonite in a monomeric solution, using N,N′-methylenebisacrylamide as crosslinker and ammonium persulfate as initiator. Fourier transform infrared (FTIR) spectral analysis showed that the XG chains had intercalated into bentonite sheets. The influence of crosslinking density and XG content were investigated. Results showed modified bentonite not only effectively increases water absorbency, but also improves water retention ability. This can be further used as a carrier matrix for the development of a drug delivery system.     

木薯淀粉-瓜尔胶复合膜的制备及性质研究

研究木薯淀粉与瓜尔胶、木薯淀粉与阴离子瓜尔胶的复合膜,淀粉含量为复合基质量的100%、80%、60%、40%和20%制成复合膜,对膜的性质用红外、热重以及扫描电镜分别表征,对膜的力学性能、水蒸气透过率和吸水性能测试。分别以强度和伸长率为指标得出最优的复合膜配比。以强度为指标的最优复合膜成分：淀粉为80%,瓜尔胶为20%,得到样本1-2与原淀粉膜相比强度提高50%,伸长率下降30%,水蒸气透过率下降15.8%,吸水率几乎没有变化。以伸长率为指标的最优膜成分：淀粉80%,阴离子瓜尔胶20%,得到样本2-1与原木薯淀粉膜相比伸长率提高了142%,但强度降低了22%,水蒸气透过率下降了5.4%,吸水性降低了5.5%。成膜条件为：淀粉糊化温度为95℃,反应时间0.5 h,烘干温度为50℃。     

瓜尔胶基高吸水性树脂的制备、溶胀行为与保水性能

以天然瓜尔胶（GG）和丙烯酸（AA）为原料,过硫酸铵（APS）为引发剂,N,N′-亚甲基双丙烯酰胺（MBA）为交联剂,采用水溶液聚合法制备了瓜尔胶接枝聚丙烯酸（GG-g-PAA）高吸水性树脂。考察了MBA浓度对树脂溶胀动力学和溶胀能力的影响,研究了树脂在不同亲水有机溶剂/水混合溶液、不同阳离子盐（NaCl、CaCl₂和FeCl₃）和阴离子盐（KNO₃、K₂SO₄和K₃PO₄）溶液中在各浓度和离子强度下的溶胀行为,测定了高吸水性树脂在室温和高温下的保水性能。结果表明,该树脂对亲水有机溶剂较为敏感,吸水倍率随着亲水有机溶剂浓度的增加迅速减小;在各种盐溶液中的吸水倍率随着离子强度的增加而下降。     

Preparation of starch‐graft‐poly(acrylamide)/attapulgite superabsorbent composite

A novel starch‐graft‐poly(acrylamide)/attapulgite superabsorbent composite was synthesized by graft copolymerization reaction of starch, acrylamide (AM), and attapulgite micropowder using N.N‐methylene‐bisacrylamide (MBA) as a crosslinker and ammonium persulphate (APS) as an initiator in aqueous solution, followed by hydrolysis with sodium hydroxide. The effects on water absorbency, such as amount of crosslinker, initiator, attapulgite, weight ratio of acrylamide to starch in the feed, gelatinization conditions of starch and molar ratio of NaOH to acrylamide, and so forth, were investigated. These superabsorbent composites were characterized by Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The water absorbencies for these superabsorbent composites in water and saline solution were investigated, and water retention tests were carried out. Results obtained from this study showed that the water absorbency of superabsorbent composite synthesized under optimal synthesis conditions with an attapulgite content of 10% exhibit absorption of 1317 g H₂O/g sample and 68 g H₂O/g sample in distilled water and in 0.9 wt % NaCl solution, respectively. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1351–1357, 2005     

Preparation and swelling characteristics of a superabsorbent nanocomposite based on natural guar gum and cation‐modified vermiculite

A series of novel superabsorbent nanocomposites were prepared by the solution radical polymerization of natural guar gum (GG), partially neutralized acrylic acid [sodium acrylate (NaA)], and cation‐exchanged vermiculite (Mⁿ⁺‐VMT) with ammonium persulfate as the initiator in the presence of the crosslinking agent N,N′‐methylene‐bis‐acrylamide. Fourier transform infrared analysis revealed that NaA was grafted onto the GG chains and that Mⁿ⁺‐VMT participated in the polymerization. X‐ray diffraction results showed that the occurrence of the cation‐exchange process changed the interlayer gap of vermiculite (VMT) and that Mⁿ⁺‐VMT was exfoliated during polymerization to form a nanocomposite. The exfoliated VMT led to better dispersion in the GG‐g‐poly(sodium acrylate) matrix, as shown by scanning electron microscopy and transmission electron microscopy analysis. Mⁿ⁺‐VMT improved the water absorption of the nanocomposite more remarkably than raw VMT, and Al³⁺‐VMT enhanced the water absorption to the highest degree. The nanocomposite exhibited intriguing overshooting swelling characteristics in a multivalent saline solution and acidic pH solution and showed switching pH‐responsive behaviors in buffer solutions between pH 2 and pH 7.2. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

聚乙烯醇/聚丙烯酸/腐植酸钠高吸水性树脂的制备及溶胀行为

以N,N＇-亚甲基双丙烯酰胺为交联剂、过硫酸铵为引发剂,采用水溶液聚合法合成了聚乙烯醇/聚丙烯酸/腐植酸钠多功能高吸水性树脂。研究了聚乙烯醇和腐植酸钠含量对树脂吸水倍率的影响,同时考察了树脂的吸水速率、溶液pH值对吸水倍率的影响及反复溶胀性能。结果表明,在体系中引入廉价的腐植酸钠,能够显著提高树脂的吸水能力。在腐植酸钠含量为10wt%时,树脂具有最高的吸水倍率,其吸蒸馏水和0.9wt%NaCl溶液分别达到1020g/g和80g/g。     

含有腐植酸的吸水性树脂在溶液及土壤环境中的性质研究

考察了含有腐植酸的吸水性树脂(HA-MA-AM)在溶液以及土壤环境中的性质。当腐植酸钾用量低于40wt%时,在环境pH值为6～7的条件下,HA-MA-AM的吸水倍率明显高于未添加腐植酸钾的MA-AM型保水剂。实验结果表明,HA-MA-AM具有较好保持水分、抑制水分蒸发的作用。     

Preparation and water absorbency of a novel poly(acrylate‐co‐acrylamide)/vermiculite superabsorbent composite

A novel poly(acrylate‐co‐acrylamide)/expanded vermiculite (EVMT) superabsorbent composite was synthesized by aqueous solution polymerization method. The water absorbency of the superabsorbent composite still reaches 850 g/g when 50 wt % EVMT is added, which is significant in decreasing the production cost of the superabsorbent composites. By controlling the molar ratio of acrylic acid monomer and acrylamide monomer, and neutralization degree of acrylic acid, the hydrophilic groups on the composite can be adjusted, and it is found that the collaborative absorbent effect of ? CONH₂, ? COOK, and ? COOH groups is superior to that of single ? CONH₂, ? COOK, or ? COOH group. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 735–739, 2007