KEY WORDSSpontaneous Polymerization / Micelle-Forming / Styrene Derivative / Radical Polymerization / We have recently found that some amphiphilic methacrylate monomers such as sodium alkyl 2-hydroxy-3-methacryloyloxypropyl phosphates and alkyl-2-methacryloyloxyethyldimethylammonium bromides spontaneously polymerize in the aqueous micellar solution, and the micelle formation is indispensable for the initiation of reaction. 1 • 2 The initiating radical species has been assumed to be produced by the thermal reaction of two monomer molecules giving the dimer diradical (1,4-diradical) followed by a chain-transfer to result the dimer monoradical, just like the thermal polymerization of methyl methacrylate, 3 which would be promoted by the micelle formation.Although styrene is the most well known thermally polymerizable monomer, spontaneous polymerization of the micelle-forming monomer having styryl group has never been reported. This paper concerns with the spontaneous polymerization of alkyldimethyl-p-vinylbenzylammonium chlorides (Cn-VBAC) as the styrene derivatives capable of forming micelles,4 so that the micellar organization would make possible to facilitate the spontaneous polymerization of these monomers like the methacrylic ester derivatives. 1 • 2 EXPERIMENTAL MonomersReagent grade 2-phenylethyl bromide and alkyl amines as starting materials for preparation of the monomers were purchased from Tokyo Kasei Co. and Kishida Chemicals Co. and were used without further purification. p-Vinylbenzyl chloride, which was prepared by chloromethylation of 2-phenylethyl bromide followed by dehydrobromination and was purified by recrystallization from hexane to remove its ortho isomer, 5 was reacted with corresponding alkyldimethylamine as described by Cochin et al. 4 The resulted crude monomers were thoroughly purified by repeated recrystallizations from ethyl acetate containing a small quantity of water for C 16 -and C 12 -VBAC and by reprecipitation using water/acetone system for C 1 -VBAC. The structure and purity of the monomers were confirmed by 1 H NMR spectra 4 recorded in CDC1 3 using a JEOL JNM-A400 spectrometer. Although the monomers contained a small quantity of water (ca. 2%) as already reported, 4 they were used for the polymeriza-1014 tion experiments without further drying.Critical micelle concentration (cmc) of the monomers in aqueous solution was determined by surface tension measurement using a du Noiiy tensiometer at room temperature. PolymerizationThe polymerization was carried out in a sealed glass tube in the dark after removing dissolved oxygen by repeated freeze-thaw cycles using a purified nitrogen. Water as polymerization solvent was distilled after ionexchanged. In the case of C 16 -and C 12 -VBAC, after heating in a thermostated water bath for a given time, the polymerizing solution was freeze-dried. The resulted monomer-polymer mixture was washed to separate each other by acetone which is a solvent for the monomer and a non-solvent for the polymer. The absence of vinyl double bond in the re...
In this paper, we report on our research an the use of the ultraviolet (UV) oxidation method to remove total organic carbon (TOC), while focusing on the phenomenon that dissolved oxygen (DO) increases at outlet of the column packed with ion exchange resins. In addition, we also researched the behavior of hydrogen peroxide that is said to be in an equilibrium state with OH (hydroxy) radical. As a result, it was found that hydrogen peroxide is decomposed/deoxidized in the ion exchange column, which leads to a DO increase at outlet of the column.
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