| Abstract
| - The atom transfer radical polymerization technique was used to synthesize the poly(methyl methacrylate-block-methacrylic acid) (P(MAA-b-MMA)) copolymer in order to study the aggregation behavior in aqueoussolution over the course of neutralization. Combinations of static and dynamic light scattering (SLS, DLS)and potentiometric titration techniques were used to investigate the size and shape of the micelle atvarious degrees of neutralization (α). By comparing the effect of different polymer chain length withsimilar MMA/MAA ratio on the aggregation behavior during neutralization, we found relatively strongentanglement of long MMA polymer chains. The comparison between the different MMA/MAA ratiosshowed that longer MMA chains produced more entanglements. Conductometric titration was used todetermine the counterion condensation phenomenon during the course of neutralization. At a criticalmicellar charge density observed at α ∼ 0.4, Na+ ions are condensed on the polymer chains. The amountof condensed Na+ was evaluated by the conductivity change, yielding the condensation ratio when thepolymer was completely neutralized.
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