| Summary: | 碩士 === 國立臺灣科技大學 === 化學工程系 === 88 === The microemulsion polymerizations of styrene with SDS and short-chain alcohols (1-butanol (C4OH), 1-pentanol (C5OH) and 1-hexanol (C6OH) ) as the surfactant and cosurfactant, respectively, were studied. The particule nucleation mechanisms in the polymerizations initiated with a water- soluble NaPS and an oil-soluble 2,2’-azobisisobutyronitrile (AIBN) were investigated by using a water-insoluble dye
(blue-70) as the probe molecule.
The polymerization rate increases with increasing initiator concentration, reaction temperature and monomer concentration, but it decreases with increasing cosurfactant concentration. The average latex particle size increases with increasing monomer and cosurfactant concentrations, but it decreases with increasing initiator concentration and reaction temperature. Molecular weight increases slightly with increasing monomer concentration, but it decreases with increasing initiator concentration, reaction temperature and
cosurfactant concentration.
The probability of particle coagulation is relatively high in the C4OH system, which is attributed to the high C4OH concentration in the water phase. The degree of homogeneous nucleation is higher when C4OH is used as the cosurfactant than the C5OH and C6OH counterparts. Increasing the initiator concentration promotes homogeneous nucleation. The efficiency of the particle nucleation initiated with AIBN is
much lower than that initiated with NaPS.
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