The influence of pH-salt Concentrations on Tuning lower critical solution temperature of Poly(NIPAAm-co-DMAA-co-DTBAVA) Multi-Environmentally terpolymer

Abstract New series of thermo-pH responsive terpolymers were fabricated. Cationic acrylate tertiary amine monomer based on vanillin was synthesized in two steps and named by [2-((ditert-butylamino)methyl)-4-formyl-6-methoxyphenyl acrylate] and abbreviated as (DTBAVA). 1H NMR, 13C NMR investigated the new compounds, and FT IR exhibited good results. The new terpolymer was fabricated by the free radical polymerization of N-isopropylacrylamide NIPAAm, 10 mol% N, N-dimethylacrylamide and 5, 10, and 20 mol% DTBAVA. The investigation process involved the chemical method such as 1H NMR and FT IR; physical methods for the solid terpolymers as glass temperature by DSC, polymer degradation by TGA, and polymer crystallinity via XRD. For terpolymer solution, gel permeation chromatography GPC was performed for molecular weights and dispersity; contact angles for identifying the hydrophilic or hydrophobic terpolymers solutions. The lower critical solution temperatures Tc,s, and cloud points Cp,s of terpolymers were recorded considering the impact of pH solutions and the concentrations of different sodium salts of (SO4-2, Cl-1, and SCN-1) kosmotropes to chaotropic in the Hofmeister series; turbidity measurements were used via UV/vis spectroscopy and micro-DSC. In a new optimization study, we will use these terpolymers in the post-polymerization with biomolecules such as chitosan, protein, and amino acids via Schiff base.