氧化淀粉基高吸水性树脂的制备及表征

以过硫酸铵为引发剂,N,N’-亚甲基双丙烯酰胺为交联剂,制备氧化淀粉―丙烯酸―丙烯酰胺高吸水性树脂,并采用红外光谱、X射线衍射等手段对产品的结构进行表征。通过单因素实验优化其制备工艺,最佳工艺条件为:氧化淀粉基体用量为50%,丙烯酸/丙烯酰胺质量比为4∶1,丙烯酸中和度为70%,引发剂过硫酸铵用量为0.5%,交联剂N,N’-亚甲基双丙烯酸胺用量为0.15%,反应温度为80℃,反应时间为3 h。此条件下,氧化淀粉基高吸水性树脂的吸水率达到972.4 g/g。     

丙烯酰胺与玉米淀粉接枝共聚物的合成及其吸水性能研究

本文以硝酸铵为引发剂N，N-亚甲基双丙烯酰胺为交联剂，将丙烯酸胺与玉米淀粉接枝共聚合成了吸水剂。实验表明，当脱水葡萄糖单元与丙烯酰胺摩尔比为1：4，交联度为0．2％时，其吸水率最高可达18g／g，其对1％食盐水的吸收率为其吸水率的90％左右。然后，将以上吸水树脂以10％NaOH于60℃水解3h，制备了另一种吸水剂，吸水率约提高了16倍，但其吸1%食盐水的能力只有其吸水能力的10％左右。     

丙烯酸盐与丙烯酰胺共聚制备耐盐性高吸水树脂

以N,N-亚甲基双丙烯酰胺为交联剂,过硫酸铵-亚硫酸钠为引发剂,采用水溶液聚合法合成了耐盐性高吸水树脂-聚(丙烯酸钠-co-丙烯酰胺).研究了单体配比、丙烯酸中和度、引发剂及交联剂用量以及反应温度对常压及加压(1.96×103Pa)下吸盐水(wNaCl=0.009)率的影响.并对其结构进行了表征.该耐盐性高吸水树脂常压和加压下吸盐水率分别为50g·g-1和18 g·g-1,且凝胶强度好.     

以两性高分子作反相悬浮稳定剂合成吸水剂

以聚（甲基丙烯酸十二酯－丙烯酸）两性共聚物为稳定剂，用反相悬浮聚合法合成了丙烯酸／丙烯酰胺／甲基丙烯酸羟乙酯三元共聚型超强吸水剂：吸蒸馏水1150mL.g^-1，吸0．9％NaCl溶液91mL.g^-1，研究了稳定剂结构及用量，单体组成，交联剂，链转移剂，中和程度等聚合条件及吸水剂性能的影响，实验表明甲基丙烯酸十二酯－丙烯酸共聚物是一种很好的反相悬浮稳定剂。     

AA/AMPS共聚型吸水树脂反相悬浮合成工艺研究

以过硫酸铵－亚酸钠为引发剂，用反相悬浮法合成丙烯酸／2－丙烯酰胺基－2－甲基丙烷磺酸共聚型吸水树脂，最佳工艺条件为：N，N－亚基双丙烯酰胺浓度＝1．082mmol.L^-1，丙烯酸中和度为80％，2－丙烯酰胺基－2－甲基丙烷磺酸的质量分数w=0.30,OP4-PEG的质量分数w=0.003，双组分引发剂浓度＝22．64mmol.L^-1，反应温度50摄氏度，共聚物吸液率（水及生理盐水）A为：AH2O=1070mL.g^-1,Anormal aaline=220mL.g^-1，抗电解质能力高于聚丙烯酸钠或丙烯酸钠与丙烯酰胺的共聚物（反相悬浮法合成），140℃以上热稳定性低于聚丙烯酸钠，保水性与其相当。     

反相悬浮法制备AA-AM共聚耐盐高吸水性树脂

对反相悬浮法制备丙烯酸 (AA)和丙烯酰胺 (AM)二元共聚高吸水性树脂的工艺进行了研究。实验表明 ,该工艺的最佳条件为 :AA 2 0g( 2 80mmol) ,n(AA)∶n(AM +AA) =0 .6 ,交联剂N ,N 亚甲基双丙烯酰胺的用量为单体总质量的 0 .2‰ ,引发剂过硫酸钾的用量为单体总质量的 0 .6‰ ,聚合温度 6 5℃ ,聚合时间 1.5h。AA -AM的吸水率为 12 5 0g·g-1,吸盐水率为 14 0g·g-1。     

P（DMAA-co—AM）水凝胶制备及其固定a-淀粉酶研究

采用氧化还原引发体系,水溶液聚合法制备P（DMAA-co-AM）水凝胶,并以其作为载体固定a-淀粉酶。采用单一变量法研究交联剂（N,N＇-亚甲基双丙烯酰胺）用量、引发剂（过硫酸铵）用量、单体浓度和单体配比对凝胶性能的影响。以水凝胶的最大平衡溶胀度为指标,得出制备P（DMAA-co-AM）水凝胶的优化条件：交联剂用量为0．3％,引发剂用量为0．6％,单体浓度为20％,N,N’-二甲基丙烯酰胺与丙烯酰胺的摩尔比为2：1。在优化条件下,采用原位聚合法固定a-淀粉酶,测定不同单体配比的P（DMAA-co-AM）水凝胶固定化a-淀粉酶的活性。     

绿色纺织印染络合剂马来酸-丙烯酸共聚物的合成

以马来酸（MA）、丙烯酸（AA）为主要单体,采用水溶液聚合法制备了马来酸-丙烯酸共聚物,探讨了影响分散力和螯合力的因素．最佳合成条件为m（MA）：m（AA）=1：3,聚合温度80～90℃,以Na2S2O8和NaHSO3为引发剂,引发剂用量（m引发剂／m总单体）为3％,产品对MnO2的分散力为1．35g·L^-1,对CaCO3的螯合力为168mg·g^-1．     

淀粉接枝丙烯酸/醋酸乙烯酯高吸水性树脂的制备

以过硫酸铵为引发剂,N,N-亚甲基双丙烯酰胺为交联剂,淀粉与丙烯酸/醋酸乙烯酯混合单体通过接枝共聚,制备了吸水及耐盐性能均较好的淀粉接枝丙烯酸/醋酸乙烯酯高吸水性树脂(CGAV)。最佳工艺条件为:淀粉10.0 g,m(混合单体)∶m(淀粉)=4∶1,w(引发剂)=0.3%,w(交联剂)=0.05%,于45℃反应2h~3 h。在最佳工艺条件下制得的CGAV吸去离子水率760 g.g-1,吸0.9%NaC l水溶液率68 g.g-1。     

碳纳米管复合聚丙烯酸钠的制备及吸水性能

以过硫酸铵(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碳纳米管/聚丙烯酸钠高吸水树脂。系统考察了碳纳米管质量分数、引发剂、交联剂和聚合温度对树脂吸水性能的影响。结果表明,以单体丙烯酸质量为基准,当交联剂,引发剂和碳纳米管质量分数分别为0.04%、0.3%和0.3%,聚合温度75℃时,所合成树脂的吸水性能最佳。添加碳纳米管后树脂表面粗糙和形成孔结构导致了其吸水性能的变化,使得碳纳米管/聚丙烯酸钠的吸水量和吸水速率明显提高,其吸去离子水和生理盐水能力分别达到1423和104g/g。该树脂重复吸水5次后,其吸水能力为1081.5g/g,达到最大吸水倍数的76.0%。     

Preparation and properties of diatomite composite superabsorbent

A novel diatomite composite superabsorbent was synthesized by solution polymerization of partially neutralized acrylic acid and diatomite, using N,N′-methylenebisacrylamide as a crosslinking agent and hydrogen peroxide and L -ascorbic acid as a redox initial system. The influences of some reaction conditions, such as diatomite content, neutralization degree of acrylic acid, amount of initiator, amount of crosslinking agent, monomer concentration, and the reaction temperature on swelling characteristic were investigated. The water absorbency of the sample prepared at optimum conditions was 99 g/g in 0.9 wt% NaCl solution. The results of swelling rate measurement showed that diatomite composite superabsorbent had better swelling rate than that of poly(sodium acrylate) prepared in the same conditions. Other properties, i.e. water retention, reswelling ability and resistance to salt, were also examined. Copyright © 2007 John Wiley & Sons, Ltd.     

均相条件下甲壳素基高吸水树脂的制备及性能研究

利用冻融循环处理破坏甲壳素致密的晶体结构和氢键相互作用,使甲壳素溶解在8 wt%NaOH/4wt%urea水溶液中,制备了碱-甲壳素均相溶液.采用静态溶液聚合法,以过硫酸铵(APS)为引发剂、甲叉双丙烯酰胺(MBA)为交联剂,在均相条件下制备了甲壳素接枝聚丙烯酸钠高吸水树脂.研究了丙烯酸、NaOH、MBA和APS用量以及反应温度和时间对产物吸水性能和得率的影响.在最优化条件下制备的树脂的最大吸蒸馏水、自来水、生理盐水和人工尿液倍率分别可达1251,455,84和77 g.g-1.采用FTIR和XRD对合成的树脂进行初步结构表征,证明反应过程中甲壳素与丙烯酸发生了接枝共聚反应,而不是甲壳素与聚丙烯酸钠的简单物理共混.     

辉光放电电解等离子体引发合成聚丙烯酸钠/腐植酸复合高吸水性树脂

以丙烯酸和腐植酸为原料,N,N-亚甲基双丙烯酰胺为交联剂,在水溶液中采用辉光放电电解等离子体引发聚合反应制备聚丙烯酸钠/腐植酸复合高吸水性树脂。 考察了放电电压、交联剂、丙烯酸中和度、后聚合温度、腐植酸钠和丙烯酸的含量对树脂吸水率的影响,讨论了树脂在0.9%氯化钠溶液中的溶胀速率和不同pH值溶液中的溶胀行为。 用红外光谱和热重分析分别对产物进行了结构表征和稳定性测试,结果表明,最佳的合成条件为：放电电压470 V、交联剂质量分数为0.6%、腐植酸钠质量分数为4%、丙烯酸质量分数为10%、中和度60%、后聚合温度70 ℃。 所得复合树脂对蒸馏水的吸水率为1152 g/g,对0.9%NaCl溶液的吸水率为89 g/g,800 ℃后复合树脂残留率为44.3%。     

表面交联的三元共聚高吸水树脂的合成及其性能研究

以丙烯酸、丙烯酰胺及丙烯磺酸钠为单体,采用水溶液聚合法制得三元共聚高吸水树脂(SAP1),用乙二醇二环氧甘油醚与氯化铝作交联剂,对SAP1进行表面交联处理得高吸水树脂SAP2。SAP2在加压下吸盐水率高,凝胶颗粒表面干爽且易分散。考察了引发温度、丙烯酸中和度、交联剂、引发剂、丙烯酰胺及丙烯磺酸钠的用量对常压下吸盐水率的影响。同时还考察了乙二醇二环氧甘油醚与无机盐用量对常压及加压下吸盐水率的影响。     

Preparation and properties of superabsorbent containing starch and sodium humate

Starch and sodium humate were utilized as raw material for synthesizing starch‐g‐poly(acrylic acid)/sodium humate (St‐g‐PAA/SH) superabsorbent by graft copolymerization reaction of starch (St) and acrylic acid (AA) in the presence of sodium humate (SH) in aqueous solution. The effect of weight ratio of AA to St, initial monomer concentration, neutralization degree of AA, amount of crosslinker, initiator and SH on water absorbency of the superabsorbent were studied. The swelling rate and swelling behavior in NaCl solution as well as reswelling ability of the superabsorbent were systematically investigated. The results showed that the superabsorbent synthesized under optimal conditions with SH content of 7.7 wt% and St content of 11.5 wt% exhibits water absorbency of 1100 g/g in distilled water and 86 g/g in 0.9 wt% NaCl solution, respectively. Introducing SH into the St‐g‐PAA polymeric network can improved the swelling rate and reswelling capability of the superabsorbent. Copyright © 2008 John Wiley & Sons, Ltd.     

Synthesis of acrylic acid-based superabsorbent interpenetrated with sodium PVA sulfate using inverse-emulsion polymerization

Acrylic acid (AA)-based superabsorbent interpenetrated with sodium poly(vinyl alcohol) (PVA) sulfate (SPS) was prepared by inverse-emulsion polymerization. The disperse phase was prepared by dissolving AA and crosslinking monomer in aqueous SPS solution. Toluene was used as the continuous phase in which oil-soluble initiator and emulsifiers were dissolved. Sorbitan monooleate and ethyl cellulose were used as emulsifiers. The maximum water and saline absorbencies were 5041 and 211.4 g/g, respectively.     

Synthesis and Characterization of Montmorillonite-Graft-Acrylic Acid Superabsorbent by Using Glow-Discharge Electrolysis Plasma

Crosslinking graft polymerization of poly acrylic/montmorillonite superabsorbent composite in aqueous solution was prepared by using glow-discharge electrolysis plasma, in which acrylic acid and acid-activated montmorillonite were used as starting materials, N,N-methylenebisacrylamide as a crosslinking agent. To optimize the synthetic conditions, seven important parameters of the graft-polymerization were examined in detail, such as the discharge voltage, discharge time, the neutralization of acrylic acid, post polymerization temperature, amounts of crosslinking agent, montmorillonite and acrylic acid used in this study. The structure, thermal stability and morphology of product were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, respectively. The absorbency of poly acrylic/montmorillonite superabsorbent was examined to yield the following results: 1,834 g/g for distilled water, 116 g/g for 0.05 mol/L and 75 g/g for 0.15 mol/L sodium chloride solution. Such excellent character could be important to use in many fields, for example, in agricultural and horticultural applications.     

PAAM高吸水树脂反相悬浮聚合

采用反相悬浮聚合法,通过部分中和丙烯酸与丙烯酰胺共聚制备了聚(丙烯酸-丙烯酰胺)(PAAM)高吸水树脂,讨论了聚合过程主要影响因素对其吸液性能的影响,并对其进行了FTIR、TGA测试,得到最佳的合成工艺配方:单体质量浓度为30%,中和度N为75%,丙烯酸与丙烯酰胺的摩尔比为7∶3,交联剂、引发剂和分散剂质量浓度分别为0.065%、0.7%和0.5%(相对于单体总质量),单体溶液的滴加速度为2～3mL/min,聚合温度和时间分别为70℃和1.5h。此时在蒸馏水、0.9%NaCl溶液%(wt)中最大吸水倍率分别为Qw=1300g/g、Qs=93g/g(Qw为蒸馏水中吸水倍率,Qs为0.9%NaCl溶液中的吸水倍率,下同),树脂在320℃之前都是比较稳定的,可以适应较高的使用温度。     

Synthesis and properties of clay-based superabsorbent composite

A novel superabsorbent composites based on acrylic acid, acrylamide, and inorganic clay mineral-attapulgite were synthesized through a solution polymerization to improve water and saline absorbencies. The superabsorbent composite was characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The effects of saline solutions, amount of initiator, crosslinker and attapulgite on the water absorbency of superabsorbent composites were investigated. The water retention test of superabsorbent composites were also carried out. The superabsorbent composite exhibited improved water and saline absorbencies compared with that of crosslinked poly(acrylic acid-co-acrylamide) superabsorbent polymer. The water absorbency of the superabsorbent composite synthesized under optimal synthesis conditions with an attapulgite content of 10% reaches more than 1400 g H₂O/g and 110 g H₂O/g in distilled water and 0.9% NaCl solution, respectively.