| Polymerizable emulsifier molecule contains not only hydrophilic and hydrophobic segments but also reactive groups which can copolymerize with primary monomer. The application of polymerizable emulsifier in emulsion polymerization is effective for preparing monodispersed latex particles by one step. The latexes obtained by this method show the high stability owing to the chemical bond connection between polymerizable emulsifier and polymer chain. This article systemically investigated 60Coγrays induced emulsion polymerization of different polarity monomers with the existence of polymerizable emulsifier.1,A series of ionic polymerizable emulsifiers sodium undec-10-enoate (UDNa), N-(2-(methacryloyloxy)ethyl)-N,N-dimethylhexadecan-l-aminium bromide (MDHB), sodium 9(10)-(allyloxy)-10(9)-hydroxyoctadecanoate (HAEOANa), sodium 4-(8-(methacryloyloxy)octyl)benzenesulfonate (MOBS) andmethacryloyloxyoctyltrimethylammonium bromide (MOTB) were synthesized and characterized by FT-IR and 1H-NMR spectra.2,γrays induced styrene emulsion polymerizations were carried out with HAEOANa,MOBS and MOTB as emulsifiers, respectively. The obtained latexes were characterized by FT-IR,XFS and DSC. The results showed that these three emulsifiers all copolymerized with styrene.3,(1): The kinetics analysis results of styrene/UDNa emulsion polymerizations initiated respectively byγrays radiation and ammonium persulfate (APS) showed that the maximal polymerization rate (Rmax) increased with the increase of absorbed dose rate (APS content),monomer content and UDNa concentration. The impact exponent of emulsifier concentration on Rmaxof the two systems was about 0.7. The mechanical agitation during the emulsion polymerization process in APS initiated system accelerated the diffusion of monomer, which decreased the dependence of Rmax on monomer content. As the result, the latex particles from APS initiated system were larger and more monodisperse than those fromγrays induced systems under the same monomer content.(2): The impact exponent of dose rate on Rmax in the styrene/MDHB system was nearly the same (about 0.4) as that in the styrene/UDNa system. The result was similar to that of radiation induced emulsion polymerization with conventional emulsifier. The latex particles of styrene/MDHB system showed partial core-shell morphology by TEM images due to the special structure of MDHB.4,The impact exponent of emulsifier concentration on Rmax in bothγrays radiation induced and APS initiated MMA/UDNa systems was basically the same (about 0.2), which was smaller than that in styrene emulsion systems. It can be ascribed to the different nucleation mechanism. Oligomer micellar nucleation mechanism is dominant in styrene emulsion systems while both homogeneous nucleation mechanism and micellar nucleation mechanism are coexistent in MMA emulsion systems.5,90nm three-dimensional ordered colloidal crystals were prepared by APS initiated styrene/UDNa emulsion polymerization andγrays induced (styrene+MMA)/UDNa emulsion polymerization and the possible formation mechanism was simply discussed; Similarly, three-dimensional ordered latex particles were also prepared by AIBN induced styrene miniemulsion polymerization (styrene/MDHB/HD); In the case ofγrays static irradiation induced emulsion polymerization with UDNa as the emulsifier, colloidal crystals can be prepared by combining styrene with a polar monomer like MMA in appropriate weight ratio.6,Hexadecyl methacrylate was synthesized and used as costabilizer in styrene miniemulsion polymerization where UDNa and MDHB were used as emulsifiers, respectively. The particles' sizes were measured at different conversion and the droplet nucleation mechanism can be proved.7,Two ternary microemulsion systems styrene/UDNa/water and styrene/MDHB/water were prepared; Their polymerizations were carried out and the possible nucleation mechanism was discussed.
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