聚甲基丙烯酸缩水甘油酯为主链的咪唑型螯合树脂的合成、表征及吸附性能研究

用分散聚合法合成了聚甲基丙烯酸缩水甘油酯(PGMA),然后引入咪唑功能基合成了螯合树脂(PGMA-Imi),用傅立叶变换红外光谱(FTIR)与扫描电镜(SEM)研究了其结构与粒子表面形态,元素分析测定功能基含量,并对Cu2+等离子进行了吸附研究。结果表明所得PGMA微球为微米级、单分散性很好,所得螯合树脂(PGMA-Imi)对Cu2+的吸附效果最好。     

Polymer brush coatings for combating marine biofouling

A variety of functional polymer brushes and coatings have been developed for combating marine biofouling and biocorrosion with much less environmental impact than traditional biocides. This review summarizes recent developments in marine antifouling polymer brushes and coatings that are tethered to material surfaces and do not actively release biocides. Polymer brush coatings have been designed to inhibit molecular fouling, microfouling and macrofouling through incorporation or inclusion of multiple functionalities. Hydrophilic polymers, such as poly(ethylene glycol), hydrogels, zwitterionic polymers and polysaccharides, resist attachment of marine organisms effectively due to extensive hydration. Fouling release polymer coatings, based on fluoropolymers and poly(dimethylsiloxane) elastomers, minimize adhesion between marine organisms and material surfaces, leading to easy removal of biofoulants. Polycationic coatings are effective in reducing marine biofouling partly because of their good bactericidal properties. Recent advances in controlled radical polymerization and click chemistry have also allowed better molecular design and engineering of multifunctional brush coatings for improved antifouling efficacies.     

Well‐Defined Protein‐Based Supramolecular Nanoparticles with Excellent MRI Abilities for Multifunctional Delivery Systems

Protein‐based nanoparticles are widely used for effective biomedical applications. The objective of this work is to design series of magnetic resonance imaging (MRI)‐visible cationic supramolecular nanoparticles (PGEA@BSA‐Ad/Gd³⁺) based on bovine serum albumin (BSA) and β‐cyclodextrin‐cored star ethanolamine‐functionalized poly(glycidyl methacrylate) (CD‐PGEA) in the presence of Gd³⁺ ions for multifunctional delivery systems. CD‐PGEA is prepared via atom transfer radical polymerization and ring‐opening reaction. It is found that in the absence of Gd³⁺ ions, CD‐PGEA does not well interact with adamantine‐modified BSA (BSA‐Ad). The well‐defined PGEA@BSA‐Ad/Gd³⁺ supramolecular nanoparticles could be produced through the synergistic actions of the host–guest and electrostatic self‐assemblies by mixing aqueous solutions of CD‐PGEA, BSA‐Ad, and Gd³⁺. In comparison with CD‐PGEA assembly units, such kinds of uniform PGEA@BSA‐Ad/Gd³⁺ supramolecular nanoparticles exhibit better pDNA condensation ability, lower cytotoxicity, higher gene transfection, and easier cellular uptake. In addition, PGEA@BSA‐Ad/Gd³⁺ also produces outstanding MRI abilities, much better than Magnevist (Gd‐diethylenetriaminepentacetate acid). The present design of protein–polymer supramolecular nanoparticles with MRI contrast agents would provide a new way for multifunctional gene/drug delivery systems.     

PGMA／Al2O3填充环氧树脂灌封材料性能的研究

采用“Grafting from”的方法,制备了接枝微粒聚甲基丙烯酸缩水甘油酯／Al2O3（PGMA／Al2O3）。研究了PGMA/Al2O3及固化剂用量对环氧灌封材料的性能影响。利用扫描电镜观察了PGMA/Al2O3填充的环氧灌封材料的冲击断面的形貌。结果表明,对氧化铝粒子进行接枝改性后,复合粒子在环氧树脂灌封中得到良好的分散、增韧效果明显优于未改性的Al2O3,且在用量较少时就可明显提高环氧灌封材料的冲击强度。     

A facile method to functionalize engineering solid membrane supports for rapid and efficient oil–water separation

A facile and low-cost method is developed to functionalize engineering metal membrane supports, such as stainless steel (SS), with epoxy-containing polymer poly(glycidyl methacrylate) (PGMA) to produce a versatile and universal platform for subsequent surface modification. With a PGMA anchoring layer, we have demonstrated that hydrogel particles, such as polyacrylamide-co-poly(acrylic acid) (PAM-co-PAA), can be subsequently grafted to form functional polymer membranes for rapid and efficient oil–water separation. By contact angle and AFM measurement, we have confirmed that PAM-co-PAA hydrogel particle layer grafted on a PGMA-modified SS surface exhibits excellent selectivity as required for liquid–liquid separation, showing high affinity to water but not to oils as an ideal membrane for oil–water separation. To evaluate the separation efficiency, a simple flow-through device is employed to separate free-floating oil from water in the mixture of varied initial oil volume fraction and oil composition. Under substantially high pump flow rate up to 1.3 L/min, PAM-co-PAA hydrogel treated SS mesh can achieve excellent separation efficiency with less than 5% oil or water in the respective filtrate at the flux of as high as 540 m³/(m²·h) and retentate at the flux of 1.95 m³/(m²·h). This separation efficiency is better than, or comparable to, the maximal performance achieved using conventional gravity methods at much lower flow rate. Similar approach could be also adapted to graft superhydrophobic and superoleophilic polymer membranes with PGMA-treated engineering support to separate water from oil.     

铈盐引发高吸附量氨基化PGMA高分子微球合成及去除废水中Cr(VI)(英文)

A novel polyglycidylmethacrylate(PGMA) microspheres with high adsorption capacity of Cr(VI) was prepared by cerium(IV) initiated graft polymerization of tentacle-type polymer chains with amino group on polymer microspheres with hydroxyl groups.The micron-sized PGMA microspheres were prepared by a dispersion polym-erization method and subsequently modified by ring-opening reaction to introduce functional hydroxyl groups.The polymer microspheres were characterized by scanning electron microscopy(SEM) and Fourier transform infrared spectroscopy(FTIR).The results indicated that the polymer microspheres had an average diameter of 5 μm with uniform size distribution.The free amino group content was determined to be 5.13 mmol?g?1 for g-PGMA-NH2 mi-crospheres by potentiometric and conductometric titration methods.The Cr(VI) adsorption results indicated that the graft polymerization of tentacle-type polymer chains on the polymer microspheres could produce adsorbents with high adsorption capacity(500 mg?g?1).The polymer microspheres with grafted tentacle polymer chains have poten-tial application in large-scale removal of Cr(VI) in aqueous solution.     

PolyHIPEs: Recent advances in emulsion-templated porous polymers

Porous polymers with well-defined porosities and high specific surface areas in the form of monoliths, films, and beads are being used in a wide range of applications (reaction supports, separation membranes, tissue engineering scaffolds, controlled release matrices, responsive and smart materials) and are being used as templates for porous ceramics and porous carbons. The surge in the research and development of porous polymer systems is a rather recent phenomenon. PolyHIPEs are porous emulsion-templated polymers synthesized within high internal phase emulsions (HIPEs). HIPEs are highly viscous, paste-like emulsions in which the major, “internal” phase, usually defined as constituting more than 74% of the volume, is dispersed within the continuous, minor, “external” phase. This review focuses upon the recent advances in polyHIPEs involving innovations in polymer chemistry, macromolecular structure, multiphase architecture, surface functionalization, and nanoparticle stabilization. The effects of these innovations upon the natures of the resulting polyHIPE-based materials (including bicontinuous polymers, nanocomposites, hybrids, porous ceramics, and porous carbons) and upon the applications involving polyHIPEs are discussed. The advances in polyHIPEs described in this review are now being used to generate new families of porous materials with novel porous architectures and unique properties.     

氨基化PGMA对高氯体系中Pb（Ⅱ）吸附性能研究

通过改进的分散聚合法制备了聚合物微球PGMA,并对其氨基化,制备了单分散的PGMA-NH2高分子微球,用于对高氯体系中少量Pb（II）的吸附,考察了酸度、平衡浓度、时间、温度、吸附剂用量以及Cl-浓度等因素对吸附性能的影响,并对吸附等温线和动力学数据采用相应的模型进行拟合。研究发现,吸附等温线符合Freundlich模型,吸附动力学数据与准二级动力学模型拟合较好。高分子微球PGMA-NH2对高氯体系中少量Pb（II）的吸附容量远高于常规的市售阴离子商业树脂D201和D318,因此,该聚合物微球可用于从高氯废水中吸附少量Pb（II）。     

不同形貌PSt/PGMA双面粒子的制备和表征

溶剂挥发法制备出单分散PSt/PGMA双面粒子,用扫描电镜(SEM)、光学显微镜、红外光谱仪(FTIR)、EDS能谱仪等对其进行了表征。通过控制PSt和PGMA两种聚合物的相对分子质量(简称分子量,以下同),得到具有双面形态的雪人状、橡子状、汉堡状PSt/PGMA复合微球。选取w(十二烷基磺酸钠)=0.25%水溶液作为乳化剂制备PSt/PGMA双面粒子,依靠荧光染色分析和EDS能谱分析,得出两种聚合物相分离过程不完全,确定出了PSt/PGMA双面粒子的组成,较大半球主要为PGMA,较小半球主要为PSt。     

Facile synthesis of wormlike quantum dots-encapsulated nanoparticles and their controlled surface functionalization for effective bioapplications

Semiconductor quantum dots (QDs) are considered as ideal fluorescent probes owing to their intrinsic optical properties. It has been demonstrated that the size and shape of nanoparticles significantly influence their behaviors in biological systems. In particular, one-dimensional (1D) nanoparticles with larger aspect ratios are desirable for cellular uptake. Here, we explore a facile and green method to prepare novel 1D wormlike QDs@SiO₂ nanoparticles with controlled aspect ratios, wherein multiple QDs are arranged in the centerline of the nanoparticles. Then, an excellent cationic gene carrier, ethanolamine-functionalized poly(glycidyl methacrylate) (denoted by BUCT-PGEA), was in-situ produced via atom transfer radical polymerization on the surface of the QDs@SiO₂ nanoparticles to achieve stable surfaces (QDs@SiO₂-PGEA) for effective bioapplications. We found that the wormlike QDs@SiO₂-PGEA nanoparticles demonstrated much higher gene transfection performance than ordinary spherical counterparts. In addition, the wormlike nanoparticles with larger aspect ratio performed better than those with smaller ratio. Furthermore, the gene delivery processes including cell entry and plasmid DNA (pDNA) escape and transport were also tracked in real time by the QDs@SiO₂-PGEA/pDNA complexes. This work realized the integration of efficient gene delivery and real-time imaging within one controlled 1D nanostructure. These constructs will likely provide useful information regarding the interaction of nanoparticles with biological systems.

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