Copolymerizations of methyl 2-acetamidoacrylate (MAA) with methyl methacrylate (MMA) were carried out at 60 °C in chloroform. Copolymers containing MAA units in the range of 83-90 mol % exhibited a lower critical solution temperature (LCST), although homopolymers of MAA and MMA did not. The LCST of polymer solutions decreased with (1) an increase in the concentration of the copolymer, (2) a decrease in the MAA content in the copolymer, and (3) an increase in the concentration of salts added. The effectiveness of anionic species for reducing the LCST is NO3- < Cl- < SO42- < SO32-. Divalent anion is more effective for lowering the LCST than monovalent anion. However, there is no difference between cationic species in the salting-out effect. Sodium carbonate and sodium phosphate had a salting-in effect. Salting-out coefficients were evaluated from the relationship between the logarithm of solubility of the copolymers and the salt concentration. Salting-out coefficients of the copolymer depended not on the composition of the copolymers but on the salt added.
|Number of pages||7|
|Journal||Journal of Polymer Science, Part A: Polymer Chemistry|
|Publication status||Published - Jun 15 2002|
All Science Journal Classification (ASJC) codes
- Polymers and Plastics
- Organic Chemistry
- Materials Chemistry