Characterization of pH-sensitive hydrogels by conductimetry and calorimetry

Conference · Fri Dec 31 04:00:00 EST 1993

OSTI ID:141763

Sheppard, Jr, N F; Chen, Jey-Hsin; Lawson, H C; Salehi-Had, S; Tucker, R C ^[1]

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1. John Hopkins Univ., Baltimore, MA (United States)

The total and freezing water contents, and electrical conductivity of pH-sensitive hydrogels formed from poly(hydroxyethyl methacrylate - co - dimethylaminoethyl methacrylate) were measured as a function of copolymer composition and pH. For an 80/20 HEMA/DMAEMA gel (mole ratio), the water content increases from 37% at pH 10 of the bathing solution value at pH 10 to 90% at low pH. The difference between total and freezing water content in the gels is approximately 25%, consistent with values reported in the literature. An examination of the results in the context of the Yasuda free- volume model suggests that freezing water content, rather than total water content, may be suitable for modelling of hydrogel conductivity.

• OSTI ID: 141763
• Report Number(s): CONF-930304--
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
40 CHEMISTRY
CALORIMETRY
CHEMICAL COMPOSITION
CORRELATIONS
ELECTRIC CONDUCTIVITY
GELS
HYDRATION
METHACRYLATES
PH VALUE