Influence of cyclodextrin on the UCST- and LCST-behavior of poly(2-methacrylamido-caprolactam)-co-(N,N-dimethylacrylamide)

Alexander Burkhart; Helmut Ritter

doi:10.3762/bjoc.10.203

Influence of cyclodextrin on the UCST- and LCST-behavior of poly(2-methacrylamido-caprolactam)-co-(N,N-dimethylacrylamide)

Beilstein J Org Chem. 2014 Aug 21:10:1951-8. doi: 10.3762/bjoc.10.203. eCollection 2014.

Authors

Alexander Burkhart¹, Helmut Ritter¹

Affiliation

¹ Institute of Organic Chemistry and Macromolecular Chemistry, Heinrich-Heine-University Duesseldorf, Universitaetsstrasse 1, D-40225 Duesseldorf. Germany.

Abstract

The monomer 2-methacrylamido-caprolactam (4) was synthesized from methacryloyl chloride (3) and racemic α-amino-ε-caprolactam (2). Copolymerization of 4 with N,N-dimethylacrylamide (5) was carried out by a free-radical mechanism using 2,2'-azobis(2-methylpropionitrile) (AIBN) as an initiator. The new copolymers show a lower critical solution temperature (LCST) in water and an upper critical solution temperature (UCST) in ethanol, 1-propanol, and 1-butanol. The solubility properties of the copolymers can be influenced significantly by the addition of randomly methylated β-cyclodextrin (CD). The complexation of the copolymers with CD, was confirmed by the use of ROESY-NMR-spectroscopy.

Keywords: 2-methacrylamido-caprolactam; LCST; UCST; cyclodextrin; lysine.