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Divinyl Monomer (divinyl + monomer)
Selected AbstractsNovel divinyl monomer for preparation of unsaturated polymersJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008Song Chen Abstract To simplify the preparation of unsaturated polymers, a new type of divinyl monomer was designed in this article. The double bonds of the divinyl monomer are different not only in reactivity but also in electron density. Based on quantum chemistry calculation, (z)-4-(2-(acryloyloxy)ethoxy)-4-oxobut-2-enoic acid (cis -AEOEA) was selected as the nonelectron-donating divinyl monomer in which inactive double bond was electron deficient and can be activated by electron-donating comonomers by forming charge transfer complex (CTC) copolymerization system. So, cis- AEOEA can be used to simplify the preparation of unsaturated polymers and the content of inactive double bonds left in the polymer is controlled by electron-donating ability of comonomers. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Branched polystyrene with abundant pendant vinyl functional groups from asymmetric divinyl monomerJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 18 2008Zhong-Min Dong Abstract Branched polystyrenes with abundant pendant vinyl functional groups were prepared via radical polymerization of an asymmetric divinyl monomer, which possesses a higher reactive styryl and a lower reactive butenyl. Employing a fast reversible addition fragmentation chain transfer (RAFT) equilibrium, the concentration of active propagation chains remained at a low value and thus crosslinking did not occur until a high level of monomer conversion. The combination of a higher reaction temperature (120 °C) and RAFT agent cumyl dithiobenzoate was demonstrated to be optimal for providing both a more highly branched architecture and a higher polymer yield. The molecular weights (Mws) increased with monomer conversions because of the controlled radical polymerization characteristic, whereas the Mw distributions broadened showing a result of the gradual increase of the degree of branching. The evolution of branched structure has been confirmed by a triple detection size exclusion chromatography (TRI-SEC) and NMR technique. Furthermore, the double bonds in the side chains were successfully used for chemical modification reactions. 1H NMR and FTIR measurements reveal that the great mass of pendant vinyl groups were converted to the corresponding objective end-groups. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6023,6034, 2008 [source] Mathematical Model for Vinyl-Divinyl PolymerizationMACROMOLECULAR REACTION ENGINEERING, Issue 6 2007Seda Kizilel Abstract A mathematical model for the crosslinking copolymerization of a vinyl and divinyl monomer was developed and applied to the case of methyl methacrylate and ethylene glycol dimethacrylate batch polymerization. Model results compare favorably to the experimental findings of Li and Hamielec23 for the system investigated. The model presented utilizes the numerical fractionation technique15 and is capable of predicting a broad range of distributional properties both for pre- and post-gel operating conditions as well as polymer properties that were not experimentally determined from the experimental findings of Li and Hamielec, such as crosslink density and branching frequency. The effects of divinyl monomer fraction and chain transfer agent level on the polymer properties and the dynamics of gelation were also investigated. [source] Emulsion polymerization of divinyl monomers stabilized by sodium dodecyl sulfate and bis(2-ethylhexyl)sulfosuccinate sodium saltJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 22 2002Barbara Gawdzik Abstract The emulsion polymerization of divinyl monomers is investigated. Emulsions were obtained in the presence of sodium dodecyl sulfate and bis(2-ethylhexyl)sulfosuccinate sodium salt as surfactants. The influence of monomer type and kind of surfactant on the particle size distribution is studied. The porous structure of the broken emulsions is also determined. The results indicate that the diameter of nanospheres obtained from two divinyl monomers are significantly larger than those obtained from polystyrene. Aggregation of the particles and the pore-forming diluent added to the emulsion are responsible for the existence of pores. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3967,3973, 2002 [source] | ||||||||||