Solution polymerization of methyl acrylate initiated by 2,2′-azobis(isobutyronitrile) (AIBN) at 65 °C in the presence of molecular iodine I2 has been studied. The process, called reverse iodine transfer polymerization (RITP), efficiently controls the molecular weight (determined by size exclusion chromatography, SEC) and the structure of the polymer. For instance, poly(methyl acrylate) samples of M n,SEC ) 5700 g mol -1 and Mw/Mn ) 1.79 (Mn,theoretical ) 5500 g mol -1 ), Mn,SEC ) 10 900 g mol -1 and Mw/Mn ) 1.91 (Mn,theoretical ) 10 500 g mol -1 ), and Mn,SEC ) 21 800 g mol -1 and Mw/Mn ) 1.98 (Mn,theoretical ) 20 700 g mol -1 ) were successfully prepared. The polymerization was followed by on-line 1 H NMR spectroscopy to investigate the evolution of several compounds in the reaction medium, especially the adduct between primary radicals and iodine (A-I, where A stands for the radical fragment from the initiator), the monoadduct A-M 1-I (where M stands for the monomer unit), and the monomer conversion. The iodineend-capped structure of the polymers (A-Mn-I, where n is the mean number degree of polymerization) was further demonstrated by mass-assisted laser desorption ionization time-of-flight (MALDI-TOF). The inhibition period in RITP of n-butyl acrylate was shortened at higher temperature (about 30 min at 95 °C) without detrimental effect on the control of the molecular weight of the final polymer: M n,SEC ) 8600 g mol -1 and Mw/Mn ) 1.88 (Mn,theoretical ) 9200 g mol -1 ). Furthermore, RITP of acrylates was successfully performed in a large variety of media (in bulk, toluene, R,R,R-trifluorotoluene, anisole, methyl ethyl ketone, butyl acetate, propylene carbonate, propionitrile, and dimethylformamide). Last, the living nature of the polymer was confirmed by the preparation of a poly(methyl acrylate)-b-polystyrene block copolymer.

The kinetics of the living radical polymerization of n-butyl acrylate (BuA) in the presence of an excess of N-tert-butyl-N-(1-diethylphosphono-2,2-dimethylpropyl)-N-oxyl (DEPN) as a rate moderator has been studied in the temperature range 115-125 °C. The equilibrium rate constant K ) k d/kc between dormant and active chains was determined experimentally from the slope of ln([BuA]0/[BuA]) vs time. It obeys the following Arrhenius relation: K ) 4.93 × 10 5 exp(-119.3 kJ mol -1 /RT), i.e., K ) 1.09 × 10 -10mol L -1 at 125 °C. Some straightforward analytical kinetic equations that only depend on the excess of DEPN as the experimental parameter were established. These equations were successfully applied to simulate the DEPN-mediated polymerization of n-butyl acrylate initiated by either a styryl-DEPN alkoxyamine or an AIBN/DEPN bicomponent system. Last, the slow degradation of DEPN was considered in order to account for the upward deviation of the kinetics when a great excess of DEPN was used.

The synthesis by reversible addition‐fragmentation chain transfer (RAFT) polymerization of three phosphonated terpolymers with tailored architecture has been studied. A phosphonated methacrylate (MAUPHOS) was copolymerized with vinylidene chloride (VC2) and methyl acrylate (MA) to prepare a gradient terpolymer poly(VC2‐co‐MA‐co‐MAUPHOS). Besides, hydroxyethyl acrylate (HEA) was used as a functional monomer in RAFT polymerization to prepare a statistical poly(VC2‐co‐MA‐co‐HEA) terpolymer and a diblock poly(VC2‐co‐MA)‐b‐poly(HEA) terpolymer. The HEA‐containing polymers were then modified with a phosphonated epoxide to introduce the phosphonated group. The control of the polymerization was proven by kinetic studies (evolution of molecular weight vs. conversion) and by a successful block copolymerization. The architecture of the terpolymers was determined by the reactivity ratios of the monomers: terpolymerization of VC2, MA, and HEA leading to an ideal statistical terpolymer (no composition drift) whereas terpolymerization of VC2, MA, and the phosphonated methacrylate led to a gradient terpolymer. These terpolymers were characterized by size exclusion chromatography, 31P NMR and differential scanning calorimetry. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 13–24, 2006

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The reversible addition‐fragmentation chain‐transfer (RAFT) copolymerization of vinylidene chloride and methyl acrylate was investigated at 70 °C in benzene. Three dithioesters were synthesized in high yield by a simple and straightforward transesterification method. These dithioesters were successfully used as reversible chain‐transfer agents, as demonstrated by the increase of molecular weight with conversion, a relatively low polydispersity index (Ip = 1.5) in comparison with a blank experiment (Ip = 1.9), first‐order polymerization kinetics and efficient chain extension. Nevertheless, a transfer reaction to vinylidene chloride monomer was considered to address the limitations of the RAFT process for this system. Moreover, a retardation effect was noticeable on the kinetics, depending on the structure and concentration of the transfer agent, leading to lower rate of polymerization for lower targeted molecular weights. © 2002 Society of Chemical Industry

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Extinguishments of large scale solvent res produce large amounts of water that may contain various uorinated surfactants depending on the type of re ghting foam used. Due to their chemical nature, uorinated parts of uorinated compounds are highly resistant to biochemical and advanced oxidation processes. Therefore the current treatment for the degradation of uorinated surfactant from water used in re extinguishment is high temperature incineration of the water in halogen resistant incinerators. This paper aims to propose a process for purifying re ghting water containing uorinated surfactants.Pilot re ghting waters resulting from heptane re extinguishment with reghting foam containing a uorinated surfactant were produced. Suspended matter was estimated on the basis of turbidity measurement and uorinated not suitable for direct membrane processes because of high fouling, hence electrocoagulation and ltration were required. Electrocoagulation with aluminium electrodes at a charge loading of 600 C L −1 followed by ltration were found su cient to remove turbidity from pilot re ghting waters. Fluorinated surfactant removal was 71 77% and was not signi cantly increased by higher charge loading. Floc separation in bulk solution was achieved by ltration. Reverse osmosis of pretreated pilot re ghting water and concentrated model solutions of pretreated re ghting water were studied and though ux decline was observed, measured retention rates were 99.94 99.97%, with permeate concentrations down to 10 16 µg L −1 of uorinated surfactant at the laboratory scale. The concentrate from reverse osmosis could be recycled in electrocoagulation-ltration. Experimental results indicated that electrocoagulation and ltration followed by reverse osmosis e ciently treated the water from re extinguishment, which enables a further scale-up work.

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