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SYNTHESIS OF POLY(ETHYLENE TEREPHTHALATE-co-ETHYLENE ADIPATE) CATALYZED BY RARE EARTH ACETATES
乙酸稀土盐催化缩聚合成聚(对苯二甲酸乙二酯-co-己二酸乙二酯)

ZHU Kui,ZHENG Lina,XU Lingyun,ZHU Weipu,ZHU Guixiang,SHEN Zhiquan,
朱魁
,郑李娜,徐凌云,朱蔚璞,祝桂香,沈之荃

高分子学报 , 2009,
Abstract: Rare earth (Nd,Y,La,Dy) acetates have been synthesized and used as single component catalysts for the polycondensation of dimethyl terephthalate,adipic acid and ethylene glycol first preparing aromatic/aliphatic copolyester are poly(ethylene terephthalate-co-ethylene adipate) (PETA) with high molecular weights.The copolyesters catalyzed by different rare earth acetates were characterized by means of 1H-NMR,DSC,SEC and mechanical testing.The compositions of the coplyesters calculated by the peak integrals of...
Toughening of Epoxy Resin with Solid Amine Terminated Poly (ethylene glycol) Benzoate and Effect of Red Mud Waste Particles

BCSamanta,TMaity,SDalai,AKBanthia,

材料科学技术学报 , 2008,
Abstract: An investigation was carried out to modify the toughness of triethylene tetramine cured DGEBA (diglycidyl ether of bisphenol-A) resin using solid amine terminated poly (ethylene glycol) benzoate (ATPEGB) as modifier with and without red mud waste particles. The solid ATPEGB modifier synthesized from the acid catalyzed esterification reaction of poly (ethylene glycol) (PEG) and 4-amino benzoic acid was characterized by Fourier transform infrared spectroscopy (FT-IR) and 1H-NMR (nuclear magnetic resonance) spectroscopies, viscosity measurements, and solubility parameter calculation. The unfilled and red mud waste filled modified epoxy networks were evaluated with impact, adhesive, tensile, flexural and thermal properties by differential scanning calorimetry (DSC), thermogravimetric (TG) and dynamic mechanical analysis (DMA). The effect of modifier concentration and red mud waste particles on toughening behavior was also investigated. The optimum properties were obtained at 12.5 phr (parts per hundred parts of resin) concentration of the modifier. The ATPEGB modified cured epoxy was thermally stable up to 315℃. The morphology on fracture surfaces of cured epoxy was also analyzed by scanning electron microscopy (SEM).
Marine Derived Polysaccharides for Biomedical Applications: Chemical Modification Approaches  [PDF]
Giovanna Gomez D’Ayala,Mario Malinconico,Paola Laurienzo
Molecules , 2008, DOI: 10.3390/molecules13092069
Abstract: Polysaccharide-based biomaterials are an emerging class in several biomedical fields such as tissue regeneration, particularly for cartilage, drug delivery devices and gelentrapment systems for the immobilization of cells. Important properties of the polysaccharides include controllable biological activity, biodegradability, and their ability to form hydrogels. Most of the polysaccharides used derive from natural sources; particularly, alginate and chitin, two polysaccharides which have an extensive history of use in medicine, pharmacy and basic sciences, and can be easily extracted from marine plants (algae kelp) and crab shells, respectively. The recent rediscovery of poly-saccharidebased materials is also attributable to new synthetic routes for their chemical modification, with the aim of promoting new biological activities and/or to modify the final properties of the biomaterials for specific purposes. These synthetic strategies also involve the combination of polysaccharides with other polymers. A review of the more recent research in the field of chemical modification of alginate, chitin and its derivative chitosan is presented. Moreover, we report as case studies the results of our recent work concerning various different approaches and applications of polysaccharide-based biomaterials, such as the realization of novel composites based on calcium sulphate blended with alginate and with a chemically modified chitosan, the synthesis of novel alginate-poly(ethylene glycol) copolymers and the development of a family of materials based on alginate and acrylic polymers of potential interest as drug delivery systems.
The Glycolysis of Poly(ethylene terephthalate) Waste: Lewis Acidic Ionic Liquids as High Efficient Catalysts  [PDF]
Qun Feng Yue,Lin Fei Xiao,Mi Lin Zhang,Xue Feng Bai
Polymers , 2013, DOI: 10.3390/polym5041258
Abstract: Poly(ethlyene terephthalate) waste from a local market was depolymerized by ethylene glycol (EG) in the presence of Lewis acidic ionic liquids [Bmim]ZnCl 3 and the qualitative analysis showed that bis(hydroxyethyl) terephthalate was the main product. Compared with ionic liquid [Bmim]Cl, the Lewis acidic ionic liquids showed highly catalytic activity in the glycolysis of poly(ethylene terephthalate) PET. Significantly, the conversion of PET and the yield of bis(hydroxyethyl) terephthalate were achieved at 100% and 83.8% with low catalyst ([Bmim]ZnCl 3) loading (0.16 wt %). Investigation also showed that the catalytic activity of [Bmim]ZnCl 3 was higher than that of [Bmim]MnCl 3. Catalyst [Bmim]ZnCl 3 can be reused up to five times and 1H-NMR results show that the recovered catalyst is similar to the fresh one. A mechanism of the glycolysis of PET catalyzed by [Bmim]ZnCl 3 was proposed.
Evaluation of Photoluminescence Properties of Some Poly(ethylene glycol) – Supported Coumarin Derivatives  [PDF]
Graziella Tocco,Carlo Maria Carbonaro,Gabriele Meli,Gianni Podda
Molecules , 2009, DOI: 10.3390/molecules14031044
Abstract: The immobilization of some coumarin derivatives on modified poly(ethylene glycol)s is reported and the influence of the polymeric support on the photoluminescence activity of the compounds is discussed. Upon ultraviolet excitation, the derivatives showed coumarin - related emission properties whose peak position and efficiency depended on the loading of the polymer and on the mesomeric effects of the substituents.
Multimeric, Multifunctional Derivatives of Poly(ethylene glycol)  [PDF]
Marina Zacchigna,Francesca Cateni,Sara Drioli,Gian Maria Bonora
Polymers , 2011, DOI: 10.3390/polym3031076
Abstract: This article reviews the use of multifunctional polymers founded on high-molecular weight poly(ethylene glycol) (PEG). The design of new PEG derivatives assembled in a dendrimer-like multimeric fashion or bearing different functionalities on the same molecule is described. Their use as new drug delivery systems based on the conjugation of multiple copies or diversely active drugs on the same biocompatible support is illustrated.
Poly(ethylene glycol)-poly(tetrahydrofuran)-poly(ethylene glycol) triblock copolymer : Synthesis, crystallization behavior and novel morphology
W. W. Fan,X. D. Fan,W. Tian,X. Q. Liao
eXPRESS Polymer Letters , 2013, DOI: 10.3144/expresspolymlett.2013.39
Abstract: Poly(ethylene glycol)-poly(tetrahydrofuran)-poly(ethylene glycol) (PEG-PTHF-PEG) triblock copolymer was synthesized by ring-opening polymerization of ethylene oxide using sodium alcoholate of PTHF as the macroinitiator. Its crystallization behavior and formation mechanisms of different crystal structures were studied. The study showed that the molecular weight of PEG-PTHF-PEG exhibited a significant effect on its crystallization: that is, with the increase of the copolymer’s molecular weight, the crystallizability of PTHF blocks decreased gradually, which led to the transition of copolymer from crystalline-crystalline to crystalline-amorphous. By adjusting the total molecular weight of triblock copolymer, the crystallization process can be effectively controlled, and as a result, different spherulite structures were obtained. Particularly, when PTHF blocks became amorphous, novel double concentric spherulites were observed. The morphological structures were studied by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), polarized optical microscopy (POM), and its crystalline process was investigated.
Preparation of AgI/Silica/Poly(Ethylene Glycol) Nanoparticle Colloid Solution and X-Ray Imaging Using It  [PDF]
Yoshio Kobayashi,Tetsuya Ayame,Tomohiko Nakagawa,Yohsuke Kubota,Kohsuke Gonda,Noriaki Ohuchi
ISRN Nanomaterials , 2013, DOI: 10.1155/2013/670402
Abstract: This work performed X-ray imaging of mouse by using aqueous colloid solution of AgI nanoparticles coated with silica (AgI/SiO2) and then surface-modified with poly(ethylene glycol) (PEG) (AgI/SiO2/PEG). A colloid solution of AgI nanoparticles was prepared by mixing silver perchlorate and potassium iodide in water. The AgI nanoparticles were surface-modified with 3-mercaptopropyltrimethoxysilane and then were silica-coated by a sol-gel reaction between tetraethylorthosilicate and H2O catalyzed with NaOH in ethanol. The AgI/SiO2 particle surface was modified with PEG by using methoxy PEG silane . The AgI/SiO2/PEG colloid solution revealed a computed tomography value as high as 1343.6?HU at an iodine concentration of 0.1?M, which was higher than a commercial X-ray contrast agent with the same iodine concentration. Tissues of mouse could be imaged by injecting the concentrated colloid solution into them. 1. Introduction X-ray imaging is one of the quite useful techniques for medical diagnosis. Chemicals composed of iodine absorb strongly X-ray. This property has been utilized for making X-ray images clearer, or taking high contrast images. Various iodine compounds have been thus far proposed as X-ray contrast agents [1–5], and several iodine compounds are commercially available. The iodine compounds, however, cannot be used for patients, in which adverse events as allergic reactions may be provoked by the iodine compounds [6–8]. In iodine compound nanoparticles coated with shell of materials inert for living bodies, that is, core-shell particles composed of core of iodine compound nanoparticles and shell of materials inert for living bodies, the shell prevents the iodine compound particles from contacting with living bodies. As a result, toxicity of iodine compounds will decrease. Several researchers have extensively performed coating of nanoparticles with silica, which is inert for living bodies [9–15]. Their coating methods are based on a sol-gel process. Our research group has studied silica coating of various nanoparticles with the sol-gel process [16–26]. Our group has also proposed a method for silica coating of nanoparticles of silver iodide (AgI) that is one of the iodine compounds [27–35]. The present work performed synthesis of colloid solution of silica-coated AgI nanoparticles (AgI/SiO2) by our proposed method. Furthermore, the AgI/SiO2 nanoparticles were surface-modified with poly(ethylene glycol) (PEG) (PEGylation), which is expected to improve its imaging ability in living bodies. X-ray imaging ability of the colloid solution of the PEGylated
Hydrophilization of Poly(Caprolactone) Copolymers through Introduction of Oligo(Ethylene Glycol) Moieties  [PDF]
Jonathan J. Wurth, Nils R. Blumenthal, V. Prasad Shastri
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0099157
Abstract: In this study, a new family of poly(ε-caprolactone) (PCL) copolymers that bear oligo(ethylene glycol) (OEG) moieties is described. The synthesis of three different oligo(ethylene glycol) functionalized epoxide monomers derived from 2-methyl-4-pentenoic acid, and their copolymerization with ε-caprolactone (CL) to poly(CL-co-OEG-MPO) copolymers is presented. The statistical copolymerization initiated with SnOct2/BnOH yielded the copolymers with varying OEG content and composition. The linear relationship between feed ratio and incorporation of the OEG co-monomer enables control over backbone functional group density. The introduction of OEG moieties influenced both the thermal and the hydrophilic characteristics of the copolymers. Both increasing OEG length and backbone content resulted in a decrease in static water contact angle. The introduction of OEG side chains in the PCL copolymers had no adverse influence on MC-3TE3-E1 cell interaction. However, changes to cell form factor (Φ) were observed. While unmodified PCL promoted elongated (anisotropic) morphologies (Φ = 0.094), PCL copolymer with tri-ethylene glycol side chains at or above seven percent backbone incorporation induced more isotropic cell morphologies (Φ = 0.184) similar to those observed on glass controls (Φ = 0.151).
Effect of addition of poly-(ethylene glycol) on electrical conductivity of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) hybrid
Tiejun Wang,Yingqun Qi,Jingkun Xu,Xiujie Hu,Ping Chen
Chinese Science Bulletin , 2003, DOI: 10.1360/03wb0134
Abstract: By mixing various concentrations of poly (ethylene glycol), a series of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) composite thin films were prepared. The electrical conductivity of the PEDOT-PSS/PEG thin films was measured by the four-probe method. Experimental results showed that the inclusion of poly(ethylene glycol) influenced the electrical conductivity of PEDOT-PSS film significantly. With the increase of PEG concentrations, the electrical conductivity sharply increased to reach a maximum and then slowly decreased down. Furthermore, the PEG molecular weight and environment temperature also played important roles on the electrical conductivity of PE-DOT-PSS/PEG thin films. A good linear relationship was found between ln σdc and T 1÷2 within the entire temperature range detected.
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