Article ID Journal Published Year Pages File Type
5209738 Reactive and Functional Polymers 2015 10 Pages PDF
Abstract
The reaction between diallylamine and dimethyl maleate afforded the Michael addition product dimethyl N,N-diallylaspartate [(CH2CH-CH2)2NCH(CO2Me)CH2CO2Me] I, which upon treatment with dry HCl and ester hydrolysis with aqueous HCl gave its hydrochloride salt [(CH2CH-CH2)2NH+CH(CO2Me)CH2CO2Me Cl−] II and N,N-diallylaspartic acid hydrochloride [(CH2CH-CH2)2NH+CH(CO2H)CH2CO2H Cl−] III, respectively. The new monomers II and III underwent cyclopolymerization to give, respectively, cationic polyelectrolytes (CPEs) poly(II) and poly(III). Under the influence of pH, triprotic acid (+) poly(III) was equilibrated to water-insoluble diprotic polyzwitterionic acid (±) IV, water-soluble monoprotic poly(zwitterion-anion) (± −) V, and its conjugate base polydianion (=) VI. The protonation constants of the carboxyl group and trivalent nitrogen in VI have been determined. A 20-ppm concentration of IV is effective in inhibiting the precipitation of CaSO4 from its supersaturated solution with an ≈ 100% scale inhibition efficiency for a duration of 50 h at 40 °C. The aqueous two-phase systems (ATPSs) of VI and polyoxyethylene have been studied. The transformation of water-soluble VI to insoluble IV makes it a recycling ATPS as it can be recycled by precipitation at a lower pH.
Related Topics
Physical Sciences and Engineering Chemistry Organic Chemistry
Authors
, , ,