Methacrylic Acid → HCID 88159785, compound

Participants

Reaction Conditions

Reaction Steps

A variation of the method used to prepare Microgel 2A (above) was also used. Poly(MMA/MAA/EGDMa) microgel was prepared using seed-feed emulsion polymerisation. A seed monomer mixture containing Methyl methacrylate (MMA) (Aldrich, 125.6 g), Methacrylic acid (MAA) (Aldrich, 58.7 g) and Ethyleneglycol dimethacrylate (EGDMa) (Aldrich, 1.94 g) was prepared and 14.0 g (7.5%) of the mixture added to a pre-purged (N2), stirred, solution of sodium dodecylsulphate and sodium chloride (BDH, 0.14 g and Aldrich, 0.44 g respectively, in 200 g of water), which had been heated to 80° C. K2HPO4 (2.56 g of 7% w/w solution in water) and ammonium persulphate (2.57 g of 5% w/w solution in water) were immediately added whilst maintaining a nitrogen atmosphere. The remaining monomer mixture 172 g (92.5%) was added to a stirred solution of sodium dodecylsulphate (BDH, 0.17 g in 300 g of water). After one hour of reaction, the feed monomer mixture, under constant stirring, was added to the reaction at a constant rate over a 105 min period. The reaction temperature was maintained for a further 2 h. The microgel was extensively centrifuged and washed with Milli-Q quality water. The average particle size of the particles in the collapsed state was about 250 nm. The swollen state diameter was about 700 nm at pH=7.5 (1425 nm at pH=8.1).

Provenance & Evidence