非水介质中表面引发接枝聚合法制备接枝微粒PMAA/SiO2及其对阿魏酸的氢键吸附性能

以偶联剂γ-巯丙基三甲氧基硅烷(MPMS)对微米级硅胶微粒进行表面改性,制得表面键合巯基的改性微粒MPMS-SiO2. 在非水溶剂二甲基甲酰胺(DMF)中使偶氮二异丁腈(AIBN)与MPMS-SiO2表面的巯基(-SH)构成表面引发体系(-SH/AIBN),实现甲基丙烯酸(MAA)在非水介质中的表面引发接枝聚合,制得接枝度为20 g/100 g的接枝微粒PMAA/SiO2,对其进行了表征,考察了主要因素对MAA表面引发接枝聚合的影响规律,研究了PMAA/SiO2对酚酸化合物阿魏酸的氢键吸附作用. 结果表明,-SH/AIBN可顺利引发MAA在非水介质中的接枝聚合,适宜条件为75℃,AIBN用量为单体质量的1.5%. 在PMAA/SiO2与阿魏酸分子之间可产生强氢键作用,包括高强度的多位点常规氢键与p型氢键,导致PMAA/SiO2对阿魏酸有强吸附力,吸附容量达266 mg/g. 质子性溶剂甲醇中的溶剂竞争吸附作用使阿魏酸的吸附容量降低,升高温度吸附容量降低.     

丙烯酰胺磁性接枝微粒的制备及其对氨氯地平吸附性能的研究

采用自由基聚合法,在溶液聚合体系中将功能单体丙烯酰胺(AM)接枝于改性后的Fe₃O₄磁性纳米微粒表面,制备了对S-氨氯地平有吸附性能的磁性接枝微粒Fe₃O₄@SiO₂-PAM。通过FTIR光谱、SEM、TGA和VSM进行了表征。结果表明,Fe₃O₄@SiO₂-PAM具有良好的磁性和磁响应性,饱和磁强度为52.42 emu/g,接枝度为176.8 mg/g。同时研究了接枝聚合过程,并通过动力学吸附、等温吸附及可重复使用性评估了磁性接枝微粒Fe₃O₄@SiO₂-PAM的吸附性能。磁性接枝微粒Fe₃O₄@SiO₂-PAM的吸附量达到241 mg/g,且具有重复使用价值。     

甲基丙烯酸接枝改性玉米芯对Cd2+的吸附及机理

以甲基丙烯酸为单体、高锰酸钾/浓硫酸为引发体系对玉米芯进行接枝改性,成功引入羧基官能团,结合扫描电镜、红外光谱和zeta电位等分析手段研究了吸附条件对玉米芯吸附Cd²⁺过程的影响及其吸附机理。结果表明,吸附过程符合Langmuir模型和准二级动力学方程,改性玉米芯对Cd²⁺的吸附主要是化学吸附过程,吸附速率是颗粒内扩散速率和膜扩散速率共同影响的结果;在pH 7、投加量为5 g·L^-1、温度为30℃、吸附时间为6 h的条件下,接枝改性玉米芯和原玉米芯对Cd²⁺的最大吸附容量分别为28.00 mg·g^-1和5.96 mg·g^-1,提高了近4倍;玉米芯对Cd²⁺的吸附是一个自发的吸热反应,温度越高,自发程度越大;接枝改性玉米芯对Cd²⁺的吸附过程中,参与反应的主要官能团有羧基、羟基、酰胺基和甲基等,吸附Cd²⁺后的接枝改性玉米芯表面出现褶皱和白色小颗粒,孔隙消失,电负性增大。     

壳聚糖对毛发水解液复合氨基酸的吸附性能研究

研究了壳聚对毛水解液复合氨基酸捐附性能及其影响因素,探讨了解吸的条件。结果表明在ＰＨ为６－７时,有好的吸附效果,用０．２ｍｏｌ．Ｌ＾－１ＮＨ３．Ｈ２Ｏ可解吸。     

有机接枝改性凹凸棒石对磷吸附性能的影响

有机接枝可以改善凹凸棒石粉末在吸附中的流失现象,但同时接枝反应也会影响凹凸棒石对磷的吸附效率。为了降低这一影响,对改性凹凸棒石进行接枝试验,研究不同接枝工艺对接枝产物吸附除磷效果的影响。结果表明,当丙烯酰胺、N,N′-亚甲基双丙烯酰胺、碳酸氢钠、改性凹凸棒石的质量分别为0.7、0.04、1、1 g,无水乙醇、5%过硫酸钾和水的用量分别为5、1和7 mL时,有机接枝凹凸棒石吸附剂除磷率能达到92%,是未接枝时的93.8%,吸附容量达到4.6 mg/g。     

壳聚糖改性膜材料的研究(Ⅱ)壳聚糖与甲基丙烯酸接枝共聚

以硝酸铈铵为引发剂引发壳聚糖（Cs)与甲基丙烯酸（MAA）接枝共聚。用元素分析，红外光谱。X-射线粉末衍射对接枝共聚物进行分析，并研究了接枝共聚物膜材料的力学性能和溶解性能。结果表明，由于接枝聚合，使Cs大分子原来的结晶结构受到破坏，韧性得到了一定的改善，经2%的氢氧化钠溶液处理过的Cs-g-MAA接枝共聚物膜，具有很好的耐溶剂性能。     

PAA/SiO2材料对含铜废水吸附性能研究

以γ-氯丙基三甲氧基硅烷为偶联剂,将聚烯丙基胺(PAA)接枝到硅胶表面,合成了聚烯丙基胺硅胶材料(PAA/SiO2),研究了其对Cu2+的吸附热力学、动力学和选择特性.结果表明,合成的PAA/SiO2材料的胺基含量为1.81mmol·g-1;溶液pH值对PAA/SiO2的铜吸附量影响显著,当溶液pH值为4时,材料的铜吸附量达到0.397 mmol·g-1;测定的Cu2+吸附平衡数据符合Langmuir模型,计算了吸附过程的热力学参数,结果表明吸附过程为吸热过程,升温有利吸附的进行;吸附动力学数据可用拟二级吸附动力学方程描述,得到的吸附速率常数与溶液初始浓度有关;铜锌竞争吸附结果表明PAA/SiO2材料对Cu2+有更强的吸附能力,对铜的选择性系数在2～4之间;另外,PAA/SiO2材料容易洗脱再生,5次吸附再生循环后,其铜吸附量维持在91.1％以上.     

淀粉接枝丙烯酰胺吸附铜离子性能研究

以玉米淀粉为原料,经接枝共聚反应合成了淀粉接枝丙烯酰胺。对产物进行了红外光谱、元素分析和极限黏度表征。考察了pH、接触时间、Cu2+初始浓度对产物吸附Cu2+的影响,并进行了吸附动力学、等温吸附研究。结果表明:在pH=6时,淀粉接枝丙烯酰胺对水溶液中的Cu2+有良好的吸附效果;吸附过程符合Freundlich等温式,且与拟二级动力学方程吻合,化学反应为吸附控制步骤。     

黄原胶-丙烯酰胺接枝共聚物对Cr~(3+)的吸附性能

以黄原胶为原料,丙烯酰胺为接枝单体,采用微波辐射聚合得到了黄原胶-丙烯酰胺接枝共聚物（XG-g-AM),利用红外光谱仪、X射线衍射仪对其结构进行表征。研究了 XG-g-AM对Cr³⁺的静态吸附行为,并根据吸附等温线研究了吸附热力学性质,结果表明：在研究的浓度范围内,XG-g-AM对Cr³⁺的吸附行为可用Freundlich等温式进行描述;吸附为自发的、吸热的熵增加过程,升高温度有利于吸附。     

壳聚糖对毛发水解液复合氨基酸的吸附性能研究

研究了壳聚糖对毛发水解液复合氨基酸的吸附性能及其影响因素,探讨了解吸的条件。结果表明在ｐ Ｈ 为 ６～７ 时,有好的吸附效果,用 ０２ ｍ ｏｌ· Ｌ－ １ Ｎ Ｈ３ · Ｈ２ Ｏ 可解吸。     

Adsorption behavior of copper(II) ion from aqueous solution on methacrylic acid‐grafted poly(ethylene terephthalate) fibers

The adsorption behavior of methacrylic acid‐grafted poly(ethylene terephthalate) fibers was studied toward the copper(II) ion in aqueous solutions by a batch equilibriation technique. The influence of treatment time, temperature, pH of the solution, metal ion concentration, and graft yield were considered. One hour of adsorption time was found sufficient to reach adsorption equilibrium for the copper(II) ion. It was found that the adsorption isotherm of Cu(II) fits Langmuir‐type isotherms. The adsorption process is not affected by the temperature when treated with low ion concentration, but is remarkably decreased at a high ion concentration. The heat of adsorption value was calculated as 0.71 kcal/mol. It was found that the reactive fibers are stable and regenerable by acid without losing their activity. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 766–772, 2000     

The adsorption of Cu(II) ion from aqueous solution upon acrylic acid grafted poly(ethylene terephthalate) fibers

This study is concerned with the investigation of the adsorption properties of acrylic acid grafted poly(ethylene terephthalate) fibers by the use of Cu(II) ions in aqueous solutions. Influence of pH, graft yield, contact time, concentration of the ion, and reaction temperature on the amount of ion adsorbed upon reactive fiber were investigated. The time in which the adsorption reached to the equilibrium value was determined as 1 h. The adsorption isotherm of Cu(II) ion was found to be a Langmuir type and the heat of adsorption was calculated as ?10.1 kJ mol^?1. It was observed that the adsorbed Cu(II) ion upon acrylic acid grafted poly(ethylene terephthalate) fibers could be recovered in acidic media. The fiber could also readsorb Cu(II) ions without losing its activity. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1216–1220, 2003     

黄原胶接枝聚丙烯酸水凝胶的合成及吸附性能——对亚甲基蓝染料的吸附行为

以黄原胶和丙烯酸为原料,N,N’一亚甲基双丙烯酰胺为交联剂,过硫酸钾为引发剂在水溶液中制得黄原胶接枝聚丙烯酸水凝胶,研究了其对阳离子染料MB（亚甲基蓝）的吸附行为,及对MB@吸附热力学。结果表明,XG—g—PAA水凝胶对MB的吸附行为符合Langmuir吸附等温式,其相关系数为0．9949i。     

SiO2/P(SMA-co-MMA-co-BA)树脂的制备及氯代烃吸附性能

采用悬浮聚合法制备了一种二氧化硅/聚(甲基丙烯酸十八烷基酯-co-甲基丙烯酸甲酯-co-丙烯酸丁酯)〔SiO2/P(SMA-co-MMA-co-BA)〕树脂，用于水体中氯代烃的吸附去除。通过单因素实验法研究了未改性SiO2粒径和改性SiO2用量对树脂吸附性能的影响，并利用FTIR、界面参数、SEM和BET等对材料的结构进行表征。结果表明：树脂对氯代烃的吸附选择性强、吸附速率快，且当负载的未改性SiO2粒径为50 nm、改性SiO2用量为丙烯酸酯单体总质量的1.5%时，改性树脂在6 h内对CH2Cl2、CHCl3、CCl4和C2Cl4的最大吸附倍率分别可以达到49.10、56.41、46.50和43.45 g/g，与未经SiO2改性的树脂相比吸附能力分别提高了62.91%、49.23%、42.86%和54.08%；并且经过10次吸脱附循环后，改性树脂对CHCl3的吸附倍率仍有50.30 g/g，与未经SiO2改性的树脂相比其再生性能提高了42.21%。     

Polymeric particles with conjugated polymer: Layer on its surface as effective adsorbents of amino acids

In the present paper composite polymeric particles with polypyrrole (PPy) shell have been examined as reservoirs for uptake of amino acids. The particle morphology can be designed in a way that polypyrrole load on the particle surface as well as the PPy shell thickness can be varied easily by control of the pyrrole polymerization conditions, such as monomer concentration and choice of different oxidants. Three different oxidants have been used for the preparation of PPy outer-layers, namely FeCl₃, Na₂S₂O₈, and H₃PMo₁₂O₄₀, which give the possibility to incorporate different anions into PPy structure. l- and d-alanine uptake in the presence of obtained particles has been tested as a function of particle concentration and PPy amount on the particle surface. It has been found that composite particles can adsorb quite high amounts of alanine and even show certain enantioselectivity. The uptake efficiency and selectivity depend strongly on the properties of the PPy layer, such as chemical structure (oxidized or overoxidized state) and the nature of the dopant anion.     

Polypropylene/polypropylene‐grafted acrylic acid blends for multilayer films: Preparation and characterization

Polypropylene (PP) was functionalized with acrylic acid (AA) and styrene (st) as a comonomer by means of a radical‐initiated melt‐grafting reaction. FTIR, ESCA, and ¹H‐NMR spectroscopies were used to characterize the formation of polypropylene grafted with acrylic acid (PP‐g‐AA) and polypropylene grafted with acrylic acid and styrene (PP‐g‐AAst). The content of AA grafted onto PP was determined by using volumetric titration. Blends of PP with 0–100 wt % of PP‐g‐AA were prepared by melt mixing. The effect of the modified polymer content on the surfaces of cast films was characterized through FTIR–ATR and ESCA analysis as well as contact‐angle, wetting‐tension, and ink‐adhesion measurements. The influence of the content of AA on the melting and crystallization temperature of PP was investigated by DSC. The contact angles of water on cast‐film surfaces of PP/PP‐g‐AA blends decreases with increasing modified polymer content and decreasing PP‐g‐AA molecular weight. A notorious improvement on wetting tension was observed with increasing modified polymer content and decreasing PP‐g‐AA molecular weight. From FTIR–ATR and ESCA spectra of the blends, a calculation was made of the carbonyl index on the films' surfaces. It was found that the higher the carbonyl index, the lower the contact‐angle value for the polypropylene blends. An increase in crystallization temperature of PP was observed when AA monomers were grafted into PP and with increasing PP‐g‐AA content in the blend, probably caused by a nucleation effect of AA monomers that would improve the crystallization capability of PP. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 1497–1505, 2001     

Adsorption of certain amino acids onto crosslinked diethylaminoethyl dextran microbeads

The adsorption dynamism of certain amino acids [alanine (Ala), serine (Ser), lysine (Lys), proline (Pro), and aspartic acid (Asp)] on crosslinked diethylaminoethyl (DEAE) dextran microbeads was investigated with electronic spectroscopy in aqueous solutions. Among the selected amino acids, Ala‐Pro and Ser‐Lys showed similar adsorption dynamism, but Asp showed the strongest tendency for adsorption. The interaction dynamism of Asp with crosslinked DEAE dextran microbeads was studied to determine the mechanism of this adsorption. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1985–1991, 2005     

Monodisperse core/shell latex particles containing carboxylic acid groups and their optimum acid content for pore generation

Monodisperse seeded latex particles with a core–shell morphology were prepared by copolymerizing, via dropwise addition, styrene (St)–methyl methacrylate (MMA)–acrylic acid (AA) or St–MMA–methacrylic acid (MAA) onto monodisperse seed latex particles of P(St–MMA). The seeded particles thus prepared were subjected to an alkali/acid treatment in order to generate pores in the particles. For the same carboxylic acid content, the volume expansion of the particles due to pore generation was higher in the particles containing AA than in those containing MAA. The size of the pores increased with increasing AA content. However, a maximum particle volume expansion of about 50% was observed for the particles containing 8 mol % AA in the monomer mixture employed in the second stage, and an explanation for this optimum is suggested. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 1455–1460, 1999     

亚氨乙酸型螯合吸附材料IAA-PEI/SiO2对重金属离子的螯合吸附行为

将聚胺大分子聚乙烯亚胺(PEI)接枝于微米级硅胶微粒表面,制得接枝微粒PEI/SiO2,然后使氯乙酸与PEI大分子中的伯、仲胺基发生亲核取代反应,形成亚氨乙酸(IAA)型螯合吸附材料IAA-PEI/SiO2. 研究了IAA-PEI/SiO2对重金属离子的螯合吸附行为和吸附机理. 结果表明,由于亚氨乙酸基团与重金属离子之间的静电作用与配位螯合作用,IAA-PEI/SiO2对重金属离子可产生强的螯合吸附作用,对Ni2+的吸附容量可达1.4 mmol/g;吸附过程为放热过程;在可抑制重金属离子水解的pH范围内,pH值越高,吸附能力越强;IAA-PEI/SiO2对重金属离子的吸附容量顺序为Ni2+> Pb2+>Cu2+>Cd2+.