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Different Monomers (different + monomer)
Selected AbstractsMicroporous Conjugated Poly(thienylene arylene) NetworksADVANCED MATERIALS, Issue 6 2009Johannes Schmidt Conjugated microporous polymer networks containing thienyl units are synthesized from two different monomers using oxidative polymerization. The resulting high surface area materials present interface rich, conjugated-polymer architectures, and are promising candidates for advanced material applications, such as in the field of organic electronics, for sensors and solar cells, or as polymer supports for metal catalysts. [source] Preparation, morphology, and biolabeling of fluorescent nanoparticles based on conjugated polymers by emulsion polymerizationJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 21 2010Rui Wang Abstract Novel nanoparticles based on conjugated polymer with good fluorescent properties were synthesized by Suzuki coupling reaction using certain surfactants as one kind of special emulsion polymerization. The luminescent properties of the prepared nanoparticles could be controlled by selecting different monomers. Without using substances comprising any heavy metal element, these fluorescent nanoparticles show very good biocompatibility with cells, thus showing potential applications in cell biolabeling, drug delivery tracing, organic light-emitting diodes, flat displays, and other areas. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 [source] Synthesis of polymeric core,shell particles using surface-initiated living free-radical polymerizationJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 9 2007Sarav B. Jhaveri Abstract An easy and novel approach to the synthesis of functionalized nanostructured polymeric particles is reported. The surfactant-free emulsion polymerization of methyl methacrylate in the presence of the crosslinking reagent 2-ethyl-2-(hydroxy methyl)-1,3-propanediol trimethacrylate was used to in situ crosslink colloid micelles to produce stable, crosslinked polymeric particles (diameter size , 100,300 nm). A functionalized methacrylate monomer, 2-methacryloxyethyl-2,-bromoisobutyrate, containing a dormant atom transfer radical polymerization (ATRP) living free-radical initiator, which is termed an inimer (initiator/monomer), was added to the solution during the polymerization to functionalize the surface of the particles with ATRP initiator groups. The surface-initiated ATRP of different monomers was then carried out to produce core,shell-type polymeric nanostructures. This versatile technique can be easily employed for the design of a wide variety of polymeric shells surrounding a crosslinked core while keeping good control over the sizes of the nanostructures. The particles were characterized with scanning electron microscopy, transmission electron microscopy, optical microscopy, dynamic light scattering, and Raman spectroscopy. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1575,1584, 2007 [source] Pyrrole derivatives for electrochemical coating of metallic medical devicesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 7 2004Zehava Weiss Abstract Electropolymerization of medical devices such as cardiovascular stents may posses advantages including a simple and reproducible process with the ability to control the thickness, adherence, and composition of the coating by the duration and intensity of the applied current, the monomer composition and concentration, the solvent, and the reaction conditions. The properties of the polymer can also be controlled by copolymerization of different monomers, grafting substituents to a functionalized polymer, and by entrapping biomolecules. This article describes the synthesis of a range of pyrrole-based monomers and their electrocoating onto stainless steel surfaces. N-substituted pyrrole monomers with C1,C18 alkyl chains and poly (ethylene glycol) chains were synthesized in good yields and purity. Electropolymerization of these monomers provided uniform coatings with different hydrophobicities. Studies now focus on the incorporation of drugs in the coated device for release from the surface. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1658,1667, 2004 [source] Synthesis of Poly(ester-anhydrides) Based on Different Polyester PrecursorsMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 7 2004Harri Korhonen Abstract Summary: Poly(ester-anhydrides) were synthesised from poly(L -lactide), poly(D,L -lactide), and poly(, -caprolactone) prepolymers prepared by ring-opening polymerisation of cyclic esters in the presence of 1,4-butanediol or ricinoleic acid as co-initiator. The hydroxyl group end functionality of the prepolymers was converted to carboxylic acid functionality by reaction with succinic anhydride, and the polyester precursors were coupled by melt polycondensation to give poly(ester-anhydrides). 1,4-Butanediol was used as co-initiator to study the properties of poly(ester-anhydrides) prepared from different monomers, whereas ricinoleic acid was used as co-initiator to introduce a hydrophobic fatty acid moiety to the polyester precursor. In hydrolysis tests, the poly(ester-anhydrides) showed a two-stage degradation comprising a rapid hydrolysis of anhydride linkages within three days, followed by the slower hydrolysis of the remaining polyester oligomer. Weight loss of the poly(ester-anhydrides) depended most importantly on molecular weight and thermal properties of the polyester precursors; thus, poly(ester-anhydrides) prepared from low molecular weight prepolymers having thermal transitions below 37,°C showed very fast weight loss. [source] Synthesis of Reactive Polymeric Dyes as Textile AuxiliariesMACROMOLECULAR MATERIALS & ENGINEERING, Issue 9 2003Angelina Altomare Abstract New polymeric materials containing amino-substituted azobenzene chromophores and reactive functional groups and characterized by some hydrophilicity were prepared with the aim of investigating alternative textile dyeing routes. The indicated materials were obtained either by copolymerization of suitable monomers or by modification of preformed polymers. In both cases commercial 4-amino-2,,3-dimethylazobenzene (FG) was used as chromogenic compound. According to the first synthetic strategy, the methacrylamido derivative of FG was copolymerized by free radical initiation with different monomers, such as methyl methacrylate, glycidyl methacrylate, N - tert -butylacrylamide, methacrylic acid, N -vinyl-2-pyrrolidinone, and vinyl acetate. Reaction of FG with preformed polymers containing epoxy groups generally afforded crosslinked materials. On the other hand, low FG loading extents were recorded by amidation of polymers containing carboxylic groups. Indeed, almost quantitative conversions were obtained only in the reaction of FG with anhydride containing polymers. The chemical structure, molecular weight properties, and the physical-chemical characteristics of all synthesized polymeric dyes were thoroughly investigated. Some very preliminary dyeing tests of different cloth types with the prepared polymeric dyes were also performed. UV absorption spectrum of poly(FGMAA) and poly(FGMAA- co -MMA) in chloroform at 25,°C (FGMAA,=,4-methacrylamido-2,,3-dimethylazobenzene). [source] Reactive extrusion of recycled bottle waste materialPOLYMER ENGINEERING & SCIENCE, Issue 4 2002R. Hettema The objective of this study is to investigate the effect of reactive processing of commingled bottle waste polymer in an extruder. A variety of peroxides and monomers were tested to assess their influence on the final mechanical properties of the product. The reactive extruded polymer blends were prepared in two types of extruders: a co-rotating twin-screw extruder and a Buss co-Kneader single-screw extruder. Blends were analyzed for mechanical and thermal properties. The effectiveness of the different monomers and peroxides was evaluated in terms of improvement in impact properties. It has been found that the toughness of the polymer blend is improved by reactive processing. Depending on the amount and type of reactants, the impact strength can be improved by 220%, with a slight reduction in the modulus compared to an unmodified physical blend. The most suitable monomers were n-butylmethacrylate (BMA), t-butylamino ethylmethacrylate (TBAEMA) and a combination of styrene/maleic anhydride (ST/MAH). The peroxide should have a short half-lifetime compared to the average residence time in the extruder. The most effective monomers have a high initial reactivity and low rate of evaporation at the processing conditions used. Changes in processing conditions in the extruder influence the reaction conditions and therefore the final properties of the blend. Results were interpreted in terms of residence time, melting profile and peroxide concentration. [source] Effects of hydrophilic monomer types on poly(styrene-acrylate)/montmorillonite nanocomposites made by in-site emulsion polymerization,POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 6 2009Fa-Ai Zhang Abstract Organic modified montmorillonite (OMMT) was made of pristine montmorillonite (MMT) treated with cetyl trimethylammonium bromide (CTAB). Two kinds of nanocomposites, poly(styrene-acrylate)/MMT (P(S-A)/MMT) and poly (styrene-acrylate)/OMMT (P(S-A)/OMMT) were prepared from styrene (St), hydrophilic acrylate monomer, and MMT (or OMMT) by in-site emulsion polymerization. Effects of different monomers, , -hydroxyethyl methacrylate (HEMA), acrylic acid (AA), methacryclic acid (MAA) on the thermal stability of the two nanocomposites were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TG). The structures of the nanocomposites were characterized by infrared spectroscopy (IR) and X-ray diffraction (XRD). The morphology of the nanocomposite was observed by transmission electron microscope (TEM). The results showed that the thermal stabilities of the two composites were enhanced by the addition of HEMA, AA, or MAA. The P(S-A)/OMMT nanocomposite showed higher thermal stability than that of the P(S-A)/MMT nanocomposite. In particular, HEMA improved the thermal stability of the P(S-A)/OMMT nanocomposite, which is more efficient than methacrylic acid (MA) and AA. Copyright © 2009 John Wiley & Sons, Ltd. [source] | ||||||||||