Methylmethacrylate dispersion polymerization

Kreuter and Speiser [77] developed a dispersion polymerization producing adjuvant nanospheres of polymethylmethacrylate) (PMMA). The monomer is dissolved in phosphate buffered saline and initiated by gamma radiation in the presence and absence of influenza virions. These systems showed enhanced adjuvant effect over aluminum hydroxide and prolonged antibody response. PMMA particles could be distinguished by TEM studies and the particle size was reported elsewhere to be 130 nm by photon correlation spectroscopy [75], The particle size could be reduced, producing monodisperse particles by inclusion of protective colloids, such as proteins or casein [40], Poly(methylmethacrylate) nanoparticles are also prepared... 

Surfactants have also been used to overcome the solubility limitation of synthetic polymers in CO2 (most common synthetic polymers would be considered to be C02-phobic). For example, surfactants have been used to aid in the dispersion polymerization of poly(methylmethacrylate) (PMMA) in CO2 (58-60). The surfactants used in the polymerizations of PMMA are more accurately referred to as stabilizers. The C02-phobic region acts as anchor to the growing polymer, either by physical adsorption or by chemical grafting. The C02-philic region sterically stabilizes the growing polymer particles, preventing flocculation and precipitation. When a biopolymer is not soluble in CO2, specific surfactants may be designed to aid in the solubilization of the polymer into CO2. 

The selected monomers are acrylonitrile (ACN), styrene, a-methyl styrene methylmethacrylate, hydroxyalkyl acrylates and methacrylates, vinyl chloride and others [1-10, 13-18]. The most favoured monomers for industrial production of graft polyether polyols are ACN and styrene [1-10, 18-29]. The resulting products from the radical polymerisation of vinylic monomers in polyethers are opaque, generally white dispersions (except those derived from ACN, which are yellow dispersions). A graft polyether polyol has three polymeric components ... 

Historically, guest-host systems have been the first polymeric NLO active materials to be developed. In these systems a high Per chromophore is physically dispersed in a suitable, amorphous polymeric matrix. The non centrosymmetry is induced by the usual poling procedure. Polymer matrices most frequently used include poly(methylmethacrylate), PMMA, because of its excellent optical properties, as well as other amorphous polymers with high Tg as amorphous polycarbonate (APC), polyquinoline, polyimides. Many reports have dealt initially with guest-host systems containing DRl or DANS as the dispersed chromophore. 

Emulsion polymerization of styrene or methylmethacrylate showed eui optimum weight ratio of (INUTEC)/monomer of0.0033 for PS and 0.001 for PMMA particles. The (initiator)/(monomer) ratio was kept constant at 0.00125. The monomer conversion was higher than 85 % in all cases. Latex dispersions of PS reaching 50 % and of PMMA reaching 40 % could be obtained using such low concentration of 1NUTEC SP1. 

Yeh J. M., Liou S. J., Lai M. C., Chang Y. W., Eluang C. Y. et al. (2004c), Comparative Studies of the Properties of Poly(methylmethacrylate)-clay Nanocomposite Materials Prepared by in situ Emulsion Polymerization and Solution Dispersion. JAppl Polym Sc, 94, 1936 6. 

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