聚丙烯酸钠∕高岭土复合高吸水性树脂的制备、结构与性能

以丙烯酸和高岭土为原料,用反相悬浮聚合法合成了聚丙烯酸钠/高岭土复合高吸水性树脂.研究了加入高岭土的聚丙烯酸钠复合高吸水性树脂合成中反应温度、中和度、交联剂用量、引发剂用量、高岭土添加量等影响树脂吸水性能的主要因素.结果表明,用反相悬浮聚合法合成的复合高吸水性树脂后处理容易,树脂的吸水率达到512 g/g,吸盐水率达到81 g/g,吸水速度比不加高岭土提高20%,保水能力提高15%,在250 ℃加热30 min仍能保持原吸水率的95%.用IR和TEM研究了复合高吸水性树脂的表面和结构,TEM显示高岭土的加入对树脂颗粒大小和形状有较大的影响,IR初步表明聚丙烯酸与高岭土产生了交联.     

丙烯酸(AA)-丙烯酰胺(AM)-MCM-41复合高强度吸水性树脂的合成与性能

以丙烯酸(AA),丙烯酰胺(AM)和MCM-41为原料,用反相悬浮聚合法合成了AA-AM-MCM-41复合高吸水性树脂。研究了添加有MCM-41的复合高吸水性树脂合成中分子筛的添加量、单体组成比(AA/AM)、中和度、引发剂用量、交联剂用量等影响树脂性能的主要因素。结果表明,用反相悬浮聚合法合成的AA-AM-MCM-41复合高吸水性树脂后处理容易,树脂的吸水率可达1355 g/g,吸盐率可达82 g/g,凝胶强度为3859 N/Kg,比不添加MCM-41分子筛的吸水树脂提高了2倍左右。用IR研究了复合高吸水性树脂的表面和结构,IR初步表明MCM-41与丙烯酸、丙烯酰胺产生了交联。TGA图表明复合高吸水性树脂具有较好的高温保水性。     

聚丙烯酸钠/高岭土复合高吸水性树脂的制备及性能研究

以部分中和的丙烯酸为单体，以高岭土为无机填充料，通过反相悬浮聚合法合成出聚丙烯酸钠／高岭土复合高吸水性树脂。研究了聚合条件与性能的关系，结果表明：适量高岭土的加入可提高吸水性树脂的吸水强度和耐盐性，并且有较好的热稳定性。     

反相悬浮法制备粘土复合高吸水性树脂

以丙烯酸和蒙脱土为主要原料,采用反相悬浮法合成了聚丙烯酸钠/蒙脱土复合高吸水性树脂,研究了交联剂用量、蒙脱土用量等因素对树脂吸液性能的影响,确定了最佳实验条件,在此条件下制备的复合树脂对去离子水和0.9%NaC l水溶液的吸水率分别为800g/g和92g/g,适量蒙脱土的加入可提高吸水性树脂的保水性能,FTIR初步表明蒙脱土与聚丙烯酸钠之间发生了交联反应。     

聚丙烯酸钠高吸水性树脂的研究

采用反相悬浮聚合法合成聚丙烯酸钠高吸水性树脂。讨论了水油比、分散剂种类、交联剂用量、引发剂用量、反应温度、中和度及反应时间对树脂吸水率的影响，并研究了其保水率。在最佳条件下合成的聚丙烯酸钠树脂吸水率达606％，在80℃干燥4h保水率仍达83％，该吸水性树脂还可回收再利用。     

反相悬浮聚合法合成可生物降解海藻酸钠高吸水性树脂

以丙烯酸(AA)和海藻酸钠(SA)为原料,用反相悬浮聚合法合成了聚丙烯酸钠/海藻酸钠高吸水性树脂。研究了海藻酸钠、引发剂(KPS)和交联剂(NMBA)用量、丙烯酸中和度、聚合反应温度等因素对树脂吸水率的影响以及树脂的生物降解性能。结果表明,当w(SA)=1.5%、w(KPS)=0.15%、w(NMBA)=0.1%、丙烯酸中和度为65%、聚合反应温度为75℃时,树脂对蒸馏水的吸水率为845 g/g,对生理盐水的吸水率为88 g/g,且能被土壤和微生物降解,w(SA)=10%的树脂在60 d内能够被芽苞杆菌降解52%,在土壤中能被降解36%,且降解速度随海藻酸钠质量分数的增加而加快。IR测定表明,树脂为丙烯酸盐与海藻酸钠的接枝共聚物。SEM测定表明,PAA/SA高吸水性树脂呈花瓣结构。     

聚丙烯酸钾-高岭土高吸水性树脂的制备及表征

以丙烯酸钾、高岭土为原料,通过水溶液聚合法合成高岭土-聚丙烯酸钾复合高吸水性树脂。并对单体的中和度、高岭土的添加量、交联剂用量和引发剂用量对复合高吸水性能的影响因素进行了研究。实验结果表明：当单体的中和度为85％,引发剂用景为0．25％,交联剂用量为0．015％时,可以合成出性能较好的复合型高吸水性树脂,其在蒸馏水中的吸水倍率可达728g／g。     

聚丙烯酸吸水树脂的反相悬浮聚合研究

环己烷为连续相 ,水为分散相 ,采用反相悬浮聚合法合成了聚丙烯酸高吸水性树脂。研究了碱用量、引发剂用量、交联剂用量及温度等反应条件对树脂物理状态和吸水性能的影响。制得吸水树脂最高可吸水 85 0 m L g,吸 0 .9% Na Cl溶液 12 0m L g。     

丙烯酸钠的聚合及吸水性能研究

以正己烷为连续相,司班80为分散剂,N,N‘-亚甲基双丙烯酰胺为交联剂,过硫酸钾为引发剂,采用反相悬浮聚合法合成了高吸水性聚丙烯酸钠树脂。通过调整分散剂、引发剂、交联剂的用量,制备了几种高吸水性的树脂。在制得的高吸水性聚丙烯酸钠树脂中,性能最好的树脂吸去离子水为550mL／g,吸自来水为170mL／g,吸0．9％NaCl溶液60mL／g。     

聚丙烯酸盐类高吸水性树脂的合成研究

以部分中和的丙烯酸为基本单体，采用反相悬浮聚合法，对聚丙烯酸钾、聚丙烯酸铵高吸水性树脂的合成条件进行了研究，获得了吸水树脂的吸液率与交联剂用量、引发剂用量、pH值等影响因素的关系，并利用共聚方法改进了吸水树脂的耐盐性，研制出了性能优良的高吸水性树脂。所制高吸水性树脂吸去离子水倍率≥1200mL/g（最高达2700mL/g)；耐盐性高吸水性树脂吸0．9％ NaCl水溶液倍率≥150mL/g(最高达260mL/g)。     

用丙烯酸-高岭土制备高吸水性树脂及结构表征

用丙烯酸-高岭土采用静态水溶液法制备复合吸水性树脂(简称复合树脂),考察了高岭土含量、聚合温度、丙烯酸单体的含量、丙烯酸中和度、引发剂和交联剂的用量对复合树脂吸水量的影响。实验结果表明,复合树脂的最佳制备条件为:聚合温度为70℃,丙烯酸单体的质量分数为35%,丙烯酸中和度为70%,引发剂占单体的质量分数为0.2%,交联剂占单体的质量分数为0.02%,高岭土占单体的质量分数为12%;在此条件下制备的复合树脂对蒸馏水的吸水量为920g/g,傅里叶变换红外光谱和扫描电镜表征结果表明,复合树脂是一种典型的海/岛结构,丙烯酸和高岭土之间存在共聚反应。     

含N、K的羧甲基纤维素类吸水剂的制备及性能研究

以过硫酸钾为引发剂,以N,N-亚甲基双丙烯酰胺为交联剂,用羧甲基纤维素与丙烯酸、丙烯酸钠、丙烯酸钾进行自由基接枝共聚,再以氨水中和所得接枝共聚物,制备了不同含氮量的吸水树脂。研究了原料配比及氨水中和度对吸水率的影响。结果表明:在羧甲基纤维素:丙烯酸=1:10,交联剂:引发剂:羧甲基纤维素=1:3:200的条件下,聚合物的吸水性能随体系中丙烯酸中和度的提高而变强;用氨水中和制得的聚合物的吸水性能以中和度为80%时最强,吸去离子水可达563.5g/g、自来水232.5g/g、0.9%的生理盐水100.5g/g、人工尿54.5 g/g,具有相当好的耐盐性和实用性。     

Synthesis of poly(acrylic acid)/sodium humate superabsorbent composite for agricultural use

A novel poly (acrylic acid)/sodium humate superabsorbent composite was synthesized by graft copolymerization reaction of acrylic acid (AA) on sodium humate micropowder using N,N′‐methylenebisacrylamide (MBA) as a crosslinker and potassium peroxydisulfate (KPS) as an initiator in aqueous solution. The effects on water absorbency of factors such as reaction temperature, initial monomer concentration, and degree of neutralization of AA, amount of crosslinker, initiator, and sodium humate were investigated. The superabsorbent composite was characterized by scanning electron microscopy, and the graft copolymerization reaction of AA on sodium humate micropowder was characterized by IR spectroscopy. Results obtained from this study show that the water absorbency of the superabsorbent composite synthesized under optimal conditions for synthesis with a sodium humate content of 5.3% exhibited absorption of 684 g H₂O/g sample in distilled water. Water‐retention in soil is enhanced by the use of the superabsorbent composite. The effect of superabsorbent composite on the growth of corn is reported. The superabsorbent composite may be of use as water management materials for agriculture purposes in desert and drought‐prone areas. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5137–5143, 2006     

Hydrogel composites based on linear low‐density polyethylene‐g‐poly (acrylic acid)/Kaolin or halloysite nanotubes

Two series of superabsorbent hydrogel composites were prepared using waste linear low‐density polyethylene, acrylic acid, and two types of clays including kaolin and halloysite nanotube (HNT) through emulsion polymerization. The effects of the clay content on Water absorbency were investigated to obtain a high swelling capacity. The prepared samples were characterized using FTIR, SEM, thermogravimetric analysis, XRD, solid‐state ¹³C Nuclear Magnetic Resonance spectroscopy, and ²⁹Si NMR. SEM characterization of the samples showed that the hydrogel composites have more pores and a higher swelling ratio than the clay‐free hydrogels. The hydrogel composite containing kaolin had higher water absorbency compared to the hydrogel composites with HNT. The swelling behavior of the hydrogel composite was investigated in various saline solutions. The hydrogel composite containing 5 wt % kaolin had the highest water absorbency (760 g/g in distilled water). © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40101.     

聚丙烯酸类超强吸水剂的合成与性能研究

以丙烯酸烯丙酯作为交联剂、丙烯酸(AA)为单体、过硫酸钾(KPS)为引发剂,采用溶液聚合法合成了一种聚丙烯酸类超强吸水剂。研究了合成条件对吸水性能的影响:当ρ(丙烯酸烯丙酯)=0 594g/L,ρ(KPS)=0 178g/L,单体中和度x(丙烯酸钠)=90%,c(丙烯酸钠)=4 17mol/L,聚合温度为60℃时,制得的聚合物每克吸去离子水最高达到1360mL,吸盐水(生理盐水)162mL。所得的聚合物具有良好的吸水可逆性,30min的吸水量可以达到饱和吸水量的90%。制得聚合物的热重分析表明,未吸水的该聚合物在350℃开始分解。聚合物吸水前后XRD测试结果显示:吸水前聚合物结构基本无规整性,吸水后膨胀使主链展开,结构趋于规整。     

Synthesis and properties of a poly(acrylic acid)/montmorillonite superabsorbent nanocomposite

A novel superabsorbent nanocomposite was synthesized through the intercalation polymerization of partially neutralized acrylic acid and a sodium‐type montmorillonite powder with N,N′‐methylenebisacrylamide as a crosslinker and ammonium persulfate and sodium sulfite as a type of mixed redox initiator. The effects of such factors as the amounts of the sodium‐type montmorillonite, crosslinker, and initiator and neutralization degree on the water absorbency of the nanocomposite were investigated. The structure and micrographs of the superabsorbent were characterized with Fourier transform infrared spectroscopy, X‐ray diffraction, and scanning electron microscopy. The results showed that the acrylic acid monomer was successfully intercalated into the montmorillonite layers and banded together with them. The montmorillonite layers were exfoliated and basically dispersed in the composite on a nanoscale after the polymerization. The water absorbency of the nanocomposite was much higher than that of pure poly(acrylic acid). The optimum absorbency of the nanocomposite in distilled water and saline water (NaCl concentration = 0.9%) was 1201 and 83 g/g, respectively. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5725–5730, 2006     

Synthesis,characterization, and swelling behavior of alginate‐g‐poly(sodium acrylate)/kaolin superabsorbent hydrogel composites

A novel superabsorbent composite based on sodium alginate and the inorganic clay kaolin was synthesized via the graft copolymerization of acrylic acid (AA) in an aqueous medium with methylene bisacrylamide (MBA) as a crosslinking agent and ammonium persulfate (APS) as an initiator. The effects of reaction variables, such as the MBA, AA, and APS concentrations and the alginate/kaolin weight ratio, on the water absorbency of the composite were systematically optimized. Evidence of grafting and kaolin interactions was obtained by a comparison of the Fourier transform infrared spectra of the initial substrates with that of the superabsorbent composite, and the hydrogel structure was confirmed with scanning electron microscopy. The results indicated that with an increasing alginate/kaolin weight ratio, the swelling capacity and gel content increased. The effects of various salt media were also studied, along with the swelling kinetics. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

P(AA-AM-VAc)/OMMT复合高吸水性树脂的制备

采用水溶液聚合法,以丙烯酸(AA)、丙烯酰胺(AM)、乙酸乙烯酯(VAc)为单体,有机膨润土(OMMT)为复合微粒,反应得到了P(AA-AM-VAc)/OMMT复合高吸水性树脂。通过单因素实验考察了聚合温度、单体组成、引发剂用量、交联剂用量、丙烯酸中和度、有机膨润土掺入量对复合树脂吸液率的影响,获得了最佳工艺条件。结果表明,在最佳工艺条件下制备的复合高吸水性树脂对纯净水和w(NaC l)=0.9%水溶液的吸收倍率分别为695 g/g和113 g/g。