| Acrylic-fluoropolymers with low surface free energy and good weather resistantance are more and more used in advanced exterior coatings or paints recently. However, the random copolymers were prepared so far by typical radical polymerization;the molecular weights, their distributions or polydispersitivity index (PDI), the chain structure and compositions, and then the related properties have been not effectively controlled. In this paper the random terpolymers of methyl methacrylate (MMA) with hexafluorobutyl acrylate (HFBA) and hydroxylpropyl acrylate (HPA) were synthesized by atom transfer radical polymerization with activators regenerated by electron transfer (ARGET-ATRP) in aqueous emulsion system. Their molecular weights and PDI were measured by gel permeation chromatography (GPC), the structure and compositions as well as thermal behavior of the terpolymers have been characterized by infra-red (IR) and Raman spectroscopy, nuclear magnetic resonance spectroscopy (both 1H-NMR and 13C-NMR), as well as differential scanning calorimetry (DSC).The experimental results show that the monomer emulsion was more stable when Tween-80 and sodium dodecylsulphate in the mole ratio of 2 to 1 as the formulated emulsifying agent with the total amount used in 3.2wt%. The ln ([M]0/[M]) value versus the reaction time shows authentic linear realtionship when the reaction temperature rising from 65 to 85 centigrade degree, and the linear fitting constant R2 appears to 0.9963 at 75℃that corresponds with the first order reaction characteristic of living radical polymerization including ATRP. Meanwhile, the apparent growing rate (kpapp) does not arise along with the reaction temperature for times, and appears to 7.8×10-5s-1 at 75℃, which indicates that temperature change does not influence much on the polymerization reaction rate. The number average molecular weght rises in a linear trend with the monomer conversion augment. Compared with benzyl bromide, ethyl-2-bromoisobutanoate is employed better in the controllability of the molecular weight, and the PDI value occurring low than 1.5 more ofen than not. It is informed that the latter used as an initiator could be more available to control the synthsis of the copolymer with molecular weight designed and low in PDI value in the polymerization system associated. The controllability of such polymerization reaction would be more preferable on condition that increasing the dosage of copper (Ⅱ) bromide used as catalyst and ligand respectively. Withal, ligand available poor in water solubility and oil-soluble like orthophenanthroline is better than 2, 2`-biphenyl and pentamethyl diethylenetriamine for aqueous ATRP emulsion polymerization. In addition, the employment of a cyclic polyase compound used as aid is beneficial to elevate monomer conversion and to narrow the particle size distribution, as well as the improvement in the polymerzation reaction controllability.Structure characteristic of terpolymer designed such as hydroxyl group and fluorocarbon group are identified by infra-red absorption spectroscopy (IR) and Raman spectroscopy. According to the individual peaks area of nuclear magnetic resonance spectroscopy (1H-NMR), the composition of copolymer calculated as MMA: HFBA: HPA = 60: 10.69: 0.27, which is identical with the ratio of raw materials about 60: 11.3: 3.8, and fluoro-carbon structure (-CF3 group and so on) is evident in the 13C-NMR spectroscopy again. DSC curve shows that there is only one glass state temperature of copolymer occurring about 58.7℃, besides, the purity of copolymer is verified well with the evidence of only one fusion peak in the picture. There is none of homopolymer mixed in the copolymer supported also by the GPC curve with the unique peak.
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