Summary: | 碩士 === 國立中央大學 === 化學工程與材料工程學系 === 104 === The preparation conditions , solvents, reaction temperature, the amount of initiator 2,2'Azobisisobutyronitrile(AIBN) and stabilizer Polyvinylpyrrolidone(PVP),of monodisperse polystyrene (PS) microspheres by dispersion polymerization were
investigated.
When isopropyl alcohol (IPA) was used as reaction solvent, the compatibility between IPA and PVP was poor. The nuclei collided intensely. So the particle size of
PS microspheres was not uniform. On the other hands, monodisperse PS particle was obtained by using ethanol (EtOH) or methanol (MeOH) as solvents.
PS particle size was increased with increasing reaction temperature and amount of AIBN and with decreasing amount of PVP. The maximum size of monodispersemicrospheres prepared by EtOH and MOH were 2.52μm and 2.92μm, respectively. In
addition, the PS particle sizes were increased by adding few amount (≤5%) of co-solvent (toluene or methyl ethyl ketone) in EtOH or MeOH solvents, respectively.It was considered that co-solvent was able to increase the critical chain length of PS to increase PS particle size.
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