Summary: | 碩士 === 國立成功大學 === 化學工程研究所 === 82 === In this study, naphthalene monomer and condensates modified
with different tyeps of charge-groups were synthesized, and
their abilities for dispersion of carbon particles in water
were investigated. Those condensates (PSNAF, DPSNAF, SANAF)
were synthesized by the condensation of α-Naphthylamine or N,N-
Dimeth yl-1-Naphthylamine with formaldehyde, and then followed
by the reaction with propane sultone or succinic anhydride.
Those monomers (PSNA, DPSNA, SANA, TMNA) were synthsized byα-
Naphthylamine or N,N-Dimehtyl-1-Naphthylamine with propane
sultone or succinic anhydride or iodomethane. Those
condensates and monomers acts as dispersants, and their
dispersing ability to coal and carbon black in aqueous solution
under different pH value were evaluated by viscosimetry,
scanning electron microscopy (SEM), sedimentation and the mean
particle size methods. Those results were compared the
dispersing ability with the conventional condensates (NSF). For
coal/water system, at pH=7, the condensates sow better
dispersing abilities (such as lower apparent viscosity, lower
final sediment volume and lower mean particle size) than the
corresponding monomers, and negatively charged condensates are
better than the others. At high pH value (pH=12), the similar
result can be observed. Zwitterionic-condensates (DPSNAF) show
better dispersing abilities at pH=12 than at pH=7, but still
worse than anionic-condensates (SANAF, PSNAF, NSF). For carbon
black/water system, the dispersant carrying -CCONa group in the
side chain (SANAF) shows both lower minimum viscosity and lower
optimum dosage than dispersants carrying -SO3Na group (NSF,
PSNAF)
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