Synthesis of Thermo-Responsive Polymer via Radical (Co)polymerization of N,N-Dimethyl-α-(hydroxymethyl)acrylamide with N,N-Diethylacrylamide

Yasuhiro Kohsaka; Yoshiaki Tanimoto

doi:10.3390/polym8100374

Synthesis of Thermo-Responsive Polymer via Radical (Co)polymerization of N,N-Dimethyl-α-(hydroxymethyl)acrylamide with N,N-Diethylacrylamide

Polymers (Basel). 2016 Oct 20;8(10):374. doi: 10.3390/polym8100374.

Authors

Yasuhiro Kohsaka¹, Yoshiaki Tanimoto²

Affiliations

¹ Faculty of Textile Science and Technology, Shinshu University, Nagano 386-8567, Japan. kohsaka@shinshu-u.ac.jp.
² Faculty of Textile Science and Technology, Shinshu University, Nagano 386-8567, Japan. 16fs515j@shinshu-u.ac.jp.

Abstract

α-Functionalized acrylamides have not been considered as an effective monomer design due to their poor polymerizability, although the analogues, α-functionalized acrylates, are attractive monomers of which polymers exhibit characteristic properties. In this article, we report the first example of radical polymerization of α-functionalized N,N-disubstituted acrylamide affording thermo-responsive hydrophilic polymers. N,N-dimethyl-α-(hydroxymethyl)acrylamide (DMαHAA) was (co)polymerized with N,N-diethylacrylamide (DEAA). Although the homopolymerization did not afford a polymeric product, the copolymerizations with various feed ratios yielded a series of the copolymers containing 0%⁻65% of DMαHAA units. The obtained copolymers exhibited a lower critical solution temperature (LCST) in water; the cloud points (T_cs) were linearly elevated as the contents of DMαHAA units from 32 to 64 °C, indicating that DMαHAA functioned as a more hydrophilic monomer than DEAA. The linear relationship between T_c and DMαHAA content suggests that the homopolymer, poly(DMαHAA), should have T_c at ca. 80 °C, although it is not available by direct radical homopolymerization.

Keywords: hydrophilic monomer; lower critical solution temperature; radical polymerization; temperature-responsive polymer; α-functionalized acrylamide.