The Copolymerization Of Fluoro Olefins With Vinyl Ethers

Used maleic anhydride,1H,1H,7H-dodecafluoroheptanol and ethylene oxide as raw material, two novel environmentally friendly fluorinated surfactants, sodium mono(dodecafluroheptyl ethoxy) ethanol acetate sulfonic acid maleates [H(CF2)6CH2OCH2CH2OCOCH(SO3Na)CH2COOH](FEOS-1) and sodium mono(dodecafluroheptyl terethoxy) ethanol acetate sulfonic acid maleates [H(CF2)6CH2OCH2CH20CH2CH2OCH2CH20COCH(S03Na)CH2COOH](FEOS-3) were synthesized. The structures of products were characterized by IR,1HNMR and19FNMR. The thermal stabilitiy of FEOS-1was researched, which turned out that its initial decomposition temperature was240℃and end decomposition temperature was340℃. Thermal stability of FEOS-3, whose initial decomposition temperature was250℃and end decomposition temperature was360℃, was better than that of the former, which may be caused by molecular weight. In sum, the results explained the two synthetized fluorocarbon surfactants have good thermal stability and can be used in environment of high temperature.Studies of the properties of the synthesized fluorinated surfactant showed that:(1) the values of surface tension at CMC (ycmc) were respectively25.55mN-m"1and21.63mN·m-1, lower than those of n-C7F15SO3Na and very close to PFOA’s (19.51mN·m-1), which showed high formation ability of latex beam and high surfactant.(2) their Krafft points were both below0℃, which showed highly watersoluble.Diethyl fumarate(DEF) was synthesised from fumaric and ethanol conveniently and efficiently. We reached the optimum feed ratio and best reaction conditions: n(fumaric):n(ethanol)=1:3; p-toluenesulfonic acid as catalyzer,3.0g; fumaric,1.0mol. A special aroma colorless transparent liquid was obtained after purification, and its purity was about99.0%(by GC). The chemical structures of DEF was demonstrated by FT-IR,’H-NMR and MS.Stabilized emulsions of CTFE/BVE/DEF were prepared by radical copolymerization in the presence of FEOS-3mixed with OP-10as surfactant, K2S2O8/NaHSO3as the redox initiator. In order to get the optimum feed ratio and best reaction conditions, we investigated properties of emulsion under various polymerization conditions, including varying monomers ratio, different usage of surfactant, amount of redox initiator. The results showed that the ratio of CTFE/BVE/DEF was4/5/1, and the novel fluorinated surfactant was3.0wt%of total monomers, redox initiator0.4wt%, reacting8h under45℃, and we got stable emulsion which the ratio of monomers could reached to90%. The copolymers and emulsion were characterized by means of fourier transform infrared spectra (FT-IR),1H and19F nuclearmagnetic resonance (NMR), laser particle size analyzer (LPS), transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and differential scaning calorimetry (DSC). The results showed that with DEF to join, particle size change large and particle size distribution changed narrow; Particle size turned smaller with decreasing polymerization temperature; The initiator concentration increasing made the emulsion stability enhance and latex particle size decrease; the size of emulsion on average decreased and the PDI index had the downward trend as amount of emulsifier increased. The polymers performed good thermal stability, and with the increase amount of DEF, the Tg of polymers has slightly downward trend, contact angle also has a slight decline.