Influence of Grafting on the Solution Properties and the Dissociation Behavior of Ionic/Nonionic Grafted Copolymers

✍ Scribed by Jens Weber; Volodymyr Boyko; Karl-Friedrich Arndt

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 189 KB
• Volume: 208
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.200600478

✦ Synopsis

Abstract

A new synthetic approach towards grafted terpolymers based on a poly[(methyl vinyl ether)‐alt‐(maleic anhydride)] backbone and poly(ethylene glycol) monomethyl ether (MPEG) side chains is presented. Resulting comb polymers with controllable grafting degree still have highly reactive anhydride moieties along the polymer backbone, as proved by IR spectroscopy. Grafting degree depends on the anhydride hydroxide stoichiometric ratio. It is not influenced by the molecular weight of MPEG. An increase in the grafting degree leads to a contraction of the polymer in the solution. Evaluation of potentiometric titration data gave a deeper insight into the dissociation process. The copolymers showed a two‐step dissociation behavior. No significant influence of the grafting degree on the acidic strength was observed, whilst there is a strong effect of the grafting degree on the free energy change upon neutralization Δ__G__~el~. Grafting leads to a higher change in free energy Δ__G__~el,1~ for the first step but to lower Δ__G__~el,2~ required for the second step.

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