Cloud Point Curves of Aqueous Solutions of Poly(N-ethylmethacrylamide)

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Title:Cloud Point Curves of Aqueous Solutions of Poly(N-ethylmethacrylamide)
Creators:
Bohdanecký, Miloslav
Horský, Jiří
Petrus, Vladimír
Mrkvičková, Libuše
Ulbrich, Karel
Journal or Publication Title:
Collection of Czechoslovak Chemical Communications, 58, 10, pp. 2370-2382

Abstract

Aqueous solutions of poly(<i>N</i>-ethylmethacrylamide) have a lower critical solution temperature (LCST). Cloud point curves of five polydisperse samples (<i>M</i><sub>w</sub> . 10<sup>-6</sup> = 0.06 to 2.04) in aqueous solutions at concentrations from 0.002 to 0.1 g/ml were obtained. The threshold concentration was found to be almost independent of the molecular weight. The threshold temperature decreases moderately with increasing <i>M</i> and the limiting value for infinite <i>M</i> obtained by the Shultz-Flory method is Θ<sub>L</sub><sup>PE</sup> = 340.5 K. This value is lower by 2.5 K than the temperature Θ<sub>L</sub><sup>η</sup> at which the intrinsic viscosity is proportional to the square root of the molecular weight. The difference cannot be assigned to experimental errors. The entropy-of-dilution parameter is negative (ψ = -2) and much higher than the value obtained from dilute solution properties. The differences in Θ and ψ values are discussed in terms of theory of polymer solutions where a higher-order interaction parameter is included.

Title:Cloud Point Curves of Aqueous Solutions of Poly(N-ethylmethacrylamide)
Creators:
Bohdanecký, Miloslav
Horský, Jiří
Petrus, Vladimír
Mrkvičková, Libuše
Ulbrich, Karel
Divisions:Life and Chemical Sciences > Institute of Organic Chemistry and Biochemistry > Collection of Czechoslovak Chemical Communications
Journal or Publication Title:Collection of Czechoslovak Chemical Communications
Volume:58
Number:10
Page Range:pp. 2370-2382
ISSN:0010-0765
E-ISSN:1212-6950
Publisher:Institute of Organic Chemistry and Biochemistry
Related URLs:
URLURL Type
http://dx.doi.org/10.1135/cccc19932370UNSPECIFIED
ID Code:354
Item Type:Article
Deposited On:06 Feb 2009 17:00
Last Modified:06 Feb 2009 16:00

Citation

Bohdanecký, Miloslav; Horský, Jiří; Petrus, Vladimír; Mrkvičková, Libuše; Ulbrich, Karel (1993) Cloud Point Curves of Aqueous Solutions of Poly(N-ethylmethacrylamide). Collection of Czechoslovak Chemical Communications, 58 (10). pp. 2370-2382. ISSN 0010-0765

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