疏水/亲水大孔PDVB/PAEMIPN 树脂对香兰素的吸附性能

采用分步悬浮聚合法制备了具有疏水性能的聚二乙烯基苯(polydivinylbenzene, PDVB)为第一网, 具有亲水性能的聚丙烯酰乙二胺(polyacrylethylenediamine, PAEM)为第二网的疏水/亲水大孔聚二乙烯基苯/聚丙烯酰乙二胺(PDVB/PAEM)互穿聚合物网络(interpenetrating polymer networks, IPN), 研究这类疏水/亲水IPN组成的树脂对吸附质的吸附热力学和吸附动力学; 测定了该树脂对香兰素在不同温度下的吸附等温线, 吸附等温线符合Freundlich等温吸附方程, 利用热力学函数关系计算出了吸附焓、自由能和熵变. 实验表明, PDVB/PAEM IPN树脂中疏水性的PDVB网具有疏水作用吸附能力, 亲水性的PAEM网具有氢键作用吸附能力. 吸附动力学数据符合Lagergren二级速率方程, 颗粒内扩散是吸附速率的主要控制步骤, 可采用HSDM模型加以描述.     

疏水/亲水大孔聚二乙烯基苯/聚(N-2-氨基乙基丙烯酰胺)IPN树脂的合成及对水杨酸吸附性能研究

采用分步悬浮聚合法制备了聚二乙烯基苯/聚丙烯酸甲酯(PDVB/PMA)大孔互穿聚合物网络,将其中的聚丙烯酸甲酯用乙二胺氨解,合成了具有疏水/亲水性能的聚二乙烯基苯/聚(N-2-氨基乙基丙烯酰胺)(PDVB/PNAEAM)大孔互穿聚合物网络(IPN);测定了该树脂的孔结构、含水量、弱碱交换量和溶胀性能;测定了该树脂对水杨酸在不同温度下的吸附等温线,利用热力学函数关系计算出了吸附焓、自由能和熵.推测PDVB/PNAEAM IPN树脂中疏水性的PDVB一网具有疏水作用吸附能力、亲水性的PNAEAM一网具有氢键作用吸附能力.动态吸附及脱附实验表明湿态PDVB/PNAEAM IPN树脂对水溶液中水杨酸的饱和吸附量达到46.1mg/mL.树脂可以通过4%NaOH溶液再生.PDVB/PNAEAM IPN树脂在分离工业废水中水杨酸等芳香有机酸有良好的应用前景.     

疏水/亲水性聚二乙烯基苯/聚丙烯酸大孔互穿聚合物网络树脂对苯胺的吸附性能

采用分步悬浮聚合法制备了聚二乙烯基苯/聚丙烯酸甲酯（PDVB/PMA）大孔互穿聚合物网络,将其中的聚丙烯酸甲酯转化为聚丙烯酸,得到具有疏水/亲水性能的聚二乙烯基苯/聚丙烯酸（PDVB/PAA）大孔互穿聚合物网络（IPN）,研究了这类疏水/亲水大孔PDVB/PAA IPN对苯胺的吸附热力学和吸附动力学,测定了该树脂的孔结构、含水量、弱酸交换量和溶胀性能;测定了该树脂对苯胺在不同温度下的吸附等温线,利用热力学函数关系计算了吸附焓、自由能和熵。 红外光谱显示,成功合成了疏水/亲水PDVB/PAA IPN,与PDVB、PDVB/PMA IPN树脂相比,其BET表面积以及孔容均减小,含水量为62.73％,弱酸交换量为1.91 mmol/g;对苯胺的吸附为放热、自发的过程;溶胀实验、静态解吸实验表明,PDVB/PAA IPN树脂中疏水性的PDVB网具有疏水作用吸附能力,亲水性的PAA网具有氢键作用吸附能力。 对苯胺的吸附在90 min时即可达到吸附平衡,树脂吸附苯胺符合一级速率方程,吸附速率主要受颗粒内扩散的控制,同时还受液膜扩散的影响,吸附动力学可采用HSDM模型描述。     

聚(N-对乙烯基苄基二甲胺)树脂对苯酚的吸附性能

采用二甲胺为功能化试剂,化学修饰氯甲基化苯乙烯-二乙烯基苯共聚物合成了大孔交联聚(N-对乙烯基苄基二甲胺)树脂,测得树脂的氯含量由4.2mmol/g降低到0.24mmol/g,树脂的弱碱交换量为4.0mmol/g,说明氯甲基化苯乙烯-二乙烯基苯共聚物发生胺化反应完全。在水溶液中,测定了大孔交联聚(N-对乙烯基苄基二甲胺)树脂对苯酚的吸附等温线,发现吸附平衡数据符合Freundlich等温吸附方程,相关系数大于0.99。计算得到在吸附量为15、20和25mg/g时,等量吸附焓在-20.81~-30.74kJ/mol范围内,吸附自由能和吸附熵均小于0,说明吸附过程中存在氢键作用,吸附是自发、混乱度变小的过程。比较树脂对水溶液中苯酚、对硝基苯酚和对硝基甲苯的吸附性能以及树脂对水、环己烷、乙醇和乙酸乙酯溶液中苯酚的吸附性能,进一步说明大孔交联聚(N-对乙烯基苄基二甲胺)树脂对水溶液中苯酚的吸附是基于疏水作用和氢键作用协同的机理。     

聚(N-甲基-N-对乙烯基苄基乙酰胺)对水中苯酚的吸附

由大孔交联氯甲基化聚苯乙烯进行甲胺化和乙酰化反应,合成了聚(N-甲基-N-对乙烯基苄基乙酰胺)树脂,树脂的氯含量由原来的3.95mmol/g降至0.63mmol/g.测定了树脂对水中苯酚的吸附等温线,结果表明,吸附平衡数据符合Freundlich等温方程.利用热力学函数关系计算了吸附焓、吸附自由能和吸附熵,结果表明,吸附量在10～40mg/g时,吸附焓为-71.20～-24.65kJ/mol,吸附自由能为-4.64～-6.07kJ/mol,吸附熵为-62.35～-218.56J/(mol·K).讨论了吸附过程中树脂对水中苯酚吸附的氢键与疏水作用的吸附机理.     

网络间含离子键的聚氨酯/接枝乙烯基酯树脂互穿聚合物网络 研究

分别以双酚-A型环氧树脂E-51和聚醚型环氧树脂E-46为原料合成了两种二乙胺-环氧树脂和加成多元醇(分别命名为AE-51,AE-46),将其和甲基丙烯酸一起用于合成聚氨酯/接枝乙烯基酯树脂(PU/接枝VER)互穿聚合物网络(IPN),使之在两个网络间形成离子键。实验结果表明,这类新型的IPN材料中两个网络间的互穿程度与相容性进一步提高,从而导致刚性的接枝VER对弹性的PU网络有更好的增强效果。DSC和FTIR的测定结果表明,在含AE-51的IPN中,由于离子键的作用使PU网络硬段的有序结构遭到很大程度的破坏,与AE-51和PU网络中的硬段以及VER网络有较好的相容性有关,因此这类IPN材料具有较好的力学性能。     

聚醋酸乙烯酯/聚丙烯酸甲酯互穿网络聚合物的研究 Ⅴ.互穿缠结对相区结构的稳定作用

用定量的甲苯溶胀聚醋酸乙烯酯/聚丙烯酸甲酯互穿网络聚合物(PVAc/PMA IPN),使体系处于分相的热力学条件;或醇解其中的PVAc 网络,即增加两组份的化学不相容性.动态力学谱和透射电镜等结果表明,IPN 和网络Ⅰ的交联密度较高的半 IPN 试样,没有发生进一步的相分离,证明网络互穿缠结是永久性的物理缠结,并且有强迫互容作用的存在.     

PS/PVC互贯大孔吸附树脂对脲酸的吸附研究

大孔球状PVC经苯乙烯的自由基互穿聚合反应改性得PS PVC大孔互贯树脂 ,再与有机胺反应制得了PS PVC互贯含氮大孔吸附树脂 .研究表明 ,所得吸附树脂对脲酸的吸附率可达 5 0 %以上 ,在清除体液中过量脲酸方面具有应用潜力 .同时对吸附树脂含氮量与吸附脲酸性能的关系以及其它因素的影响也进行了探讨     

淀粉/AMPS/DMC高吸水树脂的合成及对重金属离子的吸附性能

以可溶性淀粉、2-丙烯酰胺-2-甲基丙磺酸(AMPS)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)为单体,过硫酸铵为引发剂,N,N’-亚甲基双丙烯酰胺(NMBA)作交联剂,采用水溶液聚合法,合成了一种新型淀粉/AMPS/DMC高吸水树脂。通过红外光谱、扫描电镜和热重分析确定了所合成高吸水树脂的结构组成,并研究了其对Cu~(2+)、Ni~(2+)两种重金属离子的吸附能力。结果显示,淀粉/AMPS/DMC高吸水树脂对于CuSO_4和NiSO_4的吸附极限浓度均为2g/L,均在2~3 min内吸附完全,其等温吸附行为符合Freundlich方程。     

D301大孔树脂吸附钒(V)的性能研究

研究了D301大孔树脂对钒的吸附性能.结果表明,pH值对D301树脂吸附钒的影响很大,与钒在溶液中的赋存状态有关,且在pH=2时吸附效果最好:测得吸附热力学参数分别为:△H=8.97kJ/mol,△G_(313)=-5.69kJ/mol,△G_(303)=-5.2kJ/mol,△G_(293)=-4.9kJ/mol,△S=46.84J/mol·K.等温吸附服从Freundlich经验式;考察了溶液浓度、搅拌速率对交换过程的影响,并对实验数据运用相关理论模型进行拟合,结果显示钒(V)在D301树脂上吸附交换过程控制步骤为颗粒扩散控制,反应级数n为0.2391.     

Synthesis of the hydrophobic–hydrophilic macroporous poly divinylbenzene/poly(sodium acrylate) IPN resin and adsorption performance for berberine

The macroporous polydivinylbenzene/poly(methyl acrylate) interpenetrating polymer network (PDVB/PMA IPN) was prepared by the sequential suspension polymerization method, and was modified to be hydrophobic–hydrophilic macroporous polydivinylbenzene/poly (sodium acrylate) IPN (PDVB/PNaA IPN) by converting the PMA to PNaA under the condition of base. The effects of different mass ratio of the two networks and different cross‐linking degree of the second network on the pore structure and adsorption capacity of PDVB/PNaA IPN resin were studied. The PDVB/PNaA IPN resin whose adsorption quantity is the biggest was chosen to study further. The pore structure, the weak acid exchange capacity, the water retention capacity, and the swelling ability of PDVB/PNaA IPN resin were measured. The study focused on the adsorption isotherms of berberine at different temperatures. Isosteric adsorption enthalpy, adsorption Gibbs free energies can be calculated according to thermodynamic functions. The results show that the saturated adsorption quantity of berberine is up to 109.4 mg ml^?1 (wet resin) by the way of dynamic adsorption and desorption experiment. The resin could be reused by the mixture with 0.5% sodium chloride and 80% ethanol. On the one hand the hydrophobic PDVB in the PDVB/PNaA IPN resin has the ability of adsorption using π–π interaction, and on the other hand the hydrophilic PNaA in the PDVB/PNaA IPN resin has the ability of adsorption using ion exchange interaction. An important conclusion can be drawn that the PDVB/PNaA IPN resin has a promising application prospect in extracting and separating quaternary ammonium type alkaloids such as berberine. Copyright © 2009 John Wiley & Sons, Ltd.     

聚（对乙烯基苄基己内酰胺）树脂对非水体系中苯酚的吸附热力学

测定了聚（对乙烯基苄基己内酰胺）吸附树脂对正庚烷溶液中苯酚的吸附等温线,发现吸附等温线符合Freundlich等温吸附方程,相关系数大于0．99．根据热力学函数关系计算了等量吸附焓、Gibbs吸附自由能和吸附熵,等量吸附焓在30～40kJ／mol之间,推测吸附过程为氢键吸附．通过比较树脂对正庚烷中苯酚和邻硝基苯酚的吸附性能的差别,进一步论证了树脂对非水体系中酚类物质的吸附是基于氢键作用的机理．同时,聚（对乙烯基苄基己内酰胺）树脂对正庚烷溶液中苯酚的吸附相对水溶液中苯酚的吸附有更低的吸附焓变、吸附自由能变和吸附熵变．     

Durable multifunctional superhydrophobic sponge for oil/water separation and adsorption of volatile organic compounds

Inspired by the strong adhesion of mussels, a super-hydrophobic sponge was designed and prepared by a simple and inexpensive one-pot solution immersion method. The prepared superhydrophobic sponge can not only efficiently separate the oil–water mixture, more importantly, but also remove volatile organic compounds in the atmospheric environment. Polydopamine (PDA) enables polydivinylbenzene (PDVB) particles to be firmly and tightly attached to the melamine sponge skeleton, thereby making the hydrophilic sponge superhydrophobic and providing adsorption sites for volatile organic compounds in the air. The synergy enables the sponge/PDA/PDVB to quickly adsorb oils and organic substances, and it has high stability and capacity even after 20 cycles. In addition, superhydrophobic sponges can still perform outstanding adsorption performance even under highly acidic and alkaline environments. Meanwhile, the static adsorption capacity of the sponge/PDA/PDVB for gaseous toluene is 5.7 times that of activated carbon. Compared with pure PDVB, the super-hydrophobic sponge in the dynamic experiment has a penetration time increased from 6 to 390 min, which is 65 times longer than that of the PDVB, and the adsorption performance has been greatly improved. Therefore, our strategy may achieve a new effect, which can quickly and easily separate oil–water mixtures and remove volatile gaseous pollutants, and it can provide potential options for practical applications

     

D301树脂对酚类的吸附热力学研究

测定D301树脂对环己烷溶液中苯酚的吸附等温线，利用热力学函数关系计算了等量吸附焓，吸附自由能和吸附熵，等量吸附焓在30kJ/mol-35kJ/mol之间，推测吸附过程为氢键吸附。比较D301树脂对水溶液和环己烷溶液中苯酚的吸附性能，及D301树脂对环己烷溶液中苯酚和邻硝苯酚的吸附性能，进一步讨论了D301树脂对酚类物质吸附中的氢键作用。     

ADSORPTION OF CAFFEINE BY HYDROGEN DONATING ADSORBENTS BASED ON HYDROGEN BONDING

The adsorption isotherms of caffeine from aqueous solution onto three hydrogen donating adsorbents-hydroxypolystyrene,polystryene-azo-pyrogallol,and D72 resin-were measured.The adsorption enthalpies calculated from the isotherms according to the Clausisu-Clapeyron equation were -24-36kJ/mol,-32-37kJ/mol,and -19-24kJ/mol respectively.These values implied that the adsorption processes were based on hydrogen bonding.Furthermore.the mechanism of the adsorption of caffeine onto D72 resin was studied by IR spectra and the small molecular model experiments,and the results showed that the adsorption of caffeine onto hydrogen donating adsorbents was based on hydrogen bonding.     

ADSORPTION OF CAFFEINE BY HYDROGEN DONATING ADSORBENTS BASED ON HYDROGEN BONDING

1. INTRODUCTIONHydrogen bonding is a useful mechanism for adsorptive separation. The low enemy of thisbond ensures reversibility, while the directionality and the short range of this bond conferselectivity. The adsorption of hydrogen donating solutes onto an adsorbent capable of acceptinghydrogenedmberlite XAD-7, an adsorbent consisted of polycarboxylic ester--based onhydrogen bonding has been examined in detail 11-41. However, the adsorption of hydrogenaccepting solutes onto polymeric a…