Polyelectrolyte Hydrogels Based on Radiation-Modified Polyacrylamide and Products of Its Alkali Hydrolysis

The effect of molecular mass on the formation of polyelectrolyte hydrogels made from polyacrylamide (PAAm) and products of its alkali hydrolysis and on their water sorption capacity was studied. It was found that the efficiency of crosslinking of both the initial polymer and its hydrolyzates noticeably decreased on passing from high-molecular-mass to low-molecular-mass PAAm. Hydrogels prepared from high-molecular-mass PAAm and its hydrolyzates exhibited a greater limiting water uptake as compared with hydrogels made from low-molecular-mass PAAm and its hydrolyzates. A change in the degree of conversion of amide to acrylate groups from 35–41 to 47–54% had a slight effect on the maximum water uptake.     

纳米ATO改性聚丙烯腈纤维的研究

采用高导电率的纳米粉体ATO(SnO2·Sb2O3)为抗静电剂,从6种不同类型的分散剂中筛选出聚乙烯亚胺,通过设计正交实验探索出最佳工艺组合,将纳米ATO稳定均匀地分散于去离子水中,将该悬浮液作为聚丙烯腈纤维纺丝过程的预热浴,来改善聚丙烯腈纤维的抗静电性,研究了ATO用量、添加位置等对纤维抗静电性能、力学性能的影响。     

Synthesis and Absorption Power of New Polyelectrolyte Tetrazole-Containing Acrylic Hydrogels

The kinetic features of formation and equilibrium swelling in water and aqueous solutions of metals were considered for new hydrogels based on acrylic acid and methylenebisacrylamide modified with 2-methyl-5-vinyltetrazole in the polymerization stage. The influence of the concentration of the reactants on the gelation rate and the degree of equilibrium swelling was studied, as well as the influence of 2-methyl-5-vinyltetrazole on the properties of the copolymers prepared. Possible application fields for the new hydrogels were proposed.     

Treatment of the Wastewater of Finishing-and-Dyeing Production Using Polyelectrolyte Flocculants Based on Nitron Fiber Scrap

The performance of FK-1 and FK-3 cationic polyelectrolytes and of new AMF-2 amphoteric polyelectrolyte in treatment of the wastewater of finishing-and-dyeing production was studied as influenced by the concentrations of flocculant and coagulant.     

Aldol Reactions Catalyzed by Proline Functionalized Polyacrylonitrile Fiber

A proline functionalized fiber catalyst was employed for aldol reactions in water. In the presence of the fiber catalyst, the aldol reactions proceeded smoothly at 40℃ and the products were obtained in excellent yields which were higher than those obtained for the reactions catalyzed by L-proline or trans-4-hydroxy-L-proline. This newly developed fiber catalyst is applicable to the reactions of a wide range of aromatic aldehydes and exhibits excellent reusability(up to 6 times) without any additional treatment.     

脱镁叶绿酸a甲酯功能化腈纶纤维的制备

以商品级腈纶纤维(1)为原料,1,6-己二胺(Ⅰ)为胺化试剂,制得含伯胺基的腈纶纤维(2);由糊状叶绿素经酯交换反应合成脱镁叶绿酸a甲酯(Ⅱ);将Ⅱ接枝到胺化纤维2上制备了含叶绿素衍生物的功能化腈纶纤维(3),其结构经IR、元素分析和SEM表征。并对制备条件进行了优化。     

基于多肽结构的聚合物水凝胶

多肽由于具有良好的生物相容性和生物可降解性、生物活性以及自组装特性, 近年来受到了广泛的关注。将多肽自组装特性引入到聚合物中,可赋予聚合物形成凝胶性并对凝胶网络分子结构做出一定控制,进而使凝胶具有如环境响应、力学可调等结构控制性能;将特殊功能性多肽引入到化学交联的聚合物凝胶网络中,可赋予水凝胶生物功能性,如细胞黏附、酶降解、抗菌等;将多肽的凝胶网络构建、结构控制作用以及功能性同时引入获得的物理/化学双重交联凝胶不仅赋予水凝胶一定的功能性,且多肽自组装贡献的物理交联结构还能对化学交联凝胶网络起增强作用。本文综述了基于多肽自组装的物理交联聚合物水凝胶、多肽功能化的化学交联聚合物水凝胶以及基于多肽的物理/化学双重交联的聚合物水凝胶,并展望了这些水凝胶的发展前景。     

Polyelectrolyte Multilayers on Weak Polyelectrolyte Brushes

The interaction of surface‐attached weak polyelectrolyte brushes, grown directly from the surface of a solid substrate by surface‐initiated polymerization, with weak polyelectrolyte molecules in solution is studied. In addition, the formation of PEL multilayers onto such brush substrates is investigated. A strong template effect is observed and the thickness of each adsorbed layer is closely related to the thickness of the initial brush. Thus monolayers of more than 100 nm can be adsorbed in one single dipping cycle.

Layer thickness of PEI layers adsorbed to PMAA brushes as a function of the thickness of the surface‐attached monolayer. The solid line represents a case in which the PEI layer has exactly the same thickness as the brush monolayer.     

含多官能团聚丙烯腈抗菌消臭纤维的制备、结构与性能

合成了一种多官能团聚丙烯腈纤维,并测定了它的抗菌消臭性能。结果表明：此纤维含有多种含氮、含氧、杂环等官能团,其对不同菌类具备优异的杀菌活性,并且具有抗菌广播,作用时间持久和效率高等特点。     

Ionic Circuits Based on Polyelectrolyte Diodes on a Microchip

Green means go : A polyelectrolyte diode on a microchip exhibits well‐defined nonlinear rectifying behavior. This system visualizes the dynamic distribution of ions in a charged polymer phase under an electric field on a real‐time basis using fluorescence images (see picture). Multiple polyelectrolyte diodes are integrated on a microchip to produce a variety of logic gates based on ionic circuits.

     

新型含季铵基腈纶纤维的制备

以商品级腈纶为基体,二甲氨基丙胺(Ⅰ)为胺化剂,经胺化反应制得含叔胺基的腈纶纤维(1)。以溴辛烷(Ⅱ)为季铵化试剂对1进行季铵化改性,制得新型的含季铵基的腈纶纤维(2),其结构经IR和EDS表征。较佳的胺化反应条件为:以乙二醇为溶剂,Ⅰ的体积分数为30%,于118℃反应3 h。较佳的季铵化反应条件为:以乙醇为溶剂,Ⅱ.的体积分数为10%,于70℃反应6 h。     

Highly Phosphorescent Supramolecular Hydrogels Based on Platinum Emitters

We have synthesised a neutral, water‐soluble, Pt^II complex able to aggregate more efficiently in aqueous solutions than in organic solvents. The aggregates are luminescent and are not quenched by molecular oxygen. Further, we have prepared phosphorescent hydrogels utilising host–guest interactions between cyclodextrins and the tetraethylene glycol tails of the Pt^II complex. The soft assemblies feature host‐dependent emission properties.     

基于杯芳烃和紫精的电刺激响应二元水凝胶

基于上缘四脯氨酸修饰杯[4]芳烃和各种紫精客体分子的相互作用, 我们构筑了一类新型的二元超分子水凝胶. 得到结果显示, 在酸性条件下, 溴化紫精盐最易于促进四脯氨酸修饰杯[4]芳烃形成水凝胶. 并且经落球法测定了所制备水凝胶的凝胶-溶胶转变温度, 采用原子力显微镜和扫描电子显微镜表征了水凝胶的微观形态, 发现紫精的侧链对水凝胶性质具有显著影响, 包括凝胶-溶胶转变温度和微观形态. 值得注意的是, 该类水凝胶不仅具有优良的电刺激响应性, 而且能够通过化学、pH和热等多种因素进行调控.     

pH‐Switchable Bioelectrocatalysis Based on Weak Polyelectrolyte Multilayers

Weak polyelectrolytes poly(allylamine hydrochloride) (PAH) and poly(acrylic acid) (PAA) were assembled into {PAH/PAA}_n layer‐by‐layer films on electrodes. The cyclic voltammetry (CV) response of ferrocenecarboxylic acid (Fc(COOH)) at {PAH/PAA}₅ film electrodes assembled under the specific condition showed pH‐sensitive “on‐off” switching property. This property was further used to control the electrocatalytic oxidation of glucose by glucose oxidase (GOD) with Fc(COOH) as the electron transfer mediator, so that the pH‐switchable bioelectrocatalysis could be realized. The mechanism of pH‐sensitive behavior of the system was explored and believed to originate from the pH‐dependent structure change of the films.     

New Hydrogels Based on Agarose/Phytagel and Peptides

Short aromatic peptide derivatives, i.e., peptides or amino acids modified with aromatic groups, such as 9-fluorenylmethoxycarbonyl (Fmoc), can self-assemble into extracellular matrix-like hydrogels due to their nanofibrillar architecture. Among different types of amino acids, lysine (Lys) and glycine (Gly) are involved in multiple physiological processes, being key factors in the proper growth of cells, carnitine production, and collagen formation. The authors have previously successfully presented the possibility of obtaining supramolecular gels based on Fmoc-Lys-Fmoc and short peptides such as Fmoc-Gly-Gly-Gly in order to use them as a substrate for cell cultures. This paper investigates how the introduction of a gelling polymer can influence the properties of the network as well as the compatibility of the resulting materials with different cell types. A series of hydrogel compositions consisting of combinations of Fmoc-Lys-Fmoc and Fmoc-Gly-Gly-Gly with Agarose and Phytagel are thus obtained. All compositions form structured gels as shown by rheological studies and scanning electron microscopy. Fourier transform infrared spectroscopy analysis evidences the formation of H-bonds between the polysaccharides and amino acids or short peptides. Moreover, all gels exhibit good cell viability on fibroblasts as demonstrated by a live-dead staining test and good in vivo biocompatibility, which highlights the great potential of these biomaterials for biomedical applications.     

Novel Phosphorescent Hydrogels Based on an IrIII Metal Complex

Novel phosphorescent hydrogels have been explored by immobilizing an Ir^III metal complex into the matrices of hydrogels. FTIR spectra demonstrate that the Ir^III–PNaAMPS hydrogel is achieved by irreversible incorporation of positively charged [Ir(ppy)₂(dmbpy)]Cl (ppy = 2‐phenylpyrine, dmbpy = 4,4′‐dimethyl‐2,2′‐bipyridine) into negatively charged poly(2‐acrylamido‐2‐methylpropane sulfonic acid sodium) (PNaAMPS) hydrogel via electrostatic interaction. The photoluminescent spectra indicate that the Ir^III–PNaAMPS hydrogel exhibits stable phosphorescence. In vitro cultivation of human retinal pigment epithelial cells demonstrates the cytocompatibility of the Ir^III–PNaAMPS hydrogel. This work herein represents a facile pathway for fabrication of phosphorescent hydrogels.     

Preparation of Photocatalyst-supported Polyacrylonitrile Micro/Nano Composite Fiber Material and Its Photocatalytic Activity

Acomposite photocatalyst, with branch-like BiOI/Bi₂WO₆ he-terojunction deposited on the polyacrylonitrile micro/nano composite fiber(PAN MNCF), was prepared via two step hydrothermal method. The products are characterized by X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), photoluminescence(PL) spectra, UV-Vis diffuse reflection spectroscopy(UV-Vis DRS) and time-resolved fluorescence spectra. The PAN/BiOI/Bi₂WO₆ micro/nano composite fiber(PAN/BiOI/Bi₂WO₆ MNCF) showed better visible-light photocatalytic performance than PAN MNCF or BiOI/Bi₂WO₆ powder, probably ascribed to the collective effect between PAN MNCF and BiOI/Bi₂WO₆ heterojunction. Significantly, the PAN/BiOI/Bi₂WO₆ MNCF could be easily recycled through filtration method, thus avoiding the secondary pollution.     

重氮树脂型聚电解质复合物与SDS相互作用研究

由于聚电解质与表面活性剂的相互作用具有很多特别的性质而倍受关注［１～１０］,但具有感光性的重氮树脂作为正离子聚电解质与表面活性剂相互作用尚未见报道．本文研究了重氮树脂（ＤＲ）与聚苯乙烯磺酸钠（ＰＳＳ）形成的聚电解复合物（ＤＲ－ＰＳＳ）与十二烷基硫酸钠...