EFFECTS OF GAMMA RADIATION ON POLYMER IN SOLUTION. V. INTRA-MOLECULAR CROSSLINKING OF POLY(ACRYLIC ACID) IN DILUTE AQUEOUS SOLUTION

Journal Article · Fri Mar 01 04:00:00 EST 1963 · Bulletin of the Institute for Chemical Research, Kyoto University (Japan)

OSTI ID:4703893

Sakurada, I; Ikada, Y

Previous work has shown that gelation of poly(acrylic acid) in solution occurs most readily in acid form in the presence of 0.01N NaCl. The present investigation was carried out to elucidate in more detail the mechanism of crosslinking occurring in these concentration ranges. Irradiation of the deaerated solutions below the critical concentration led to main-chain scission when NaCl concentrations of solutions to be irradiated were lower than 0.01N. However, in the case of the solutions containing NaCl above 0.01N, the solutions became turbid on irradiation. Detailed studies on properties of these turbid solutions revealed that the origin of turbidity can be attributed to the formation of intra-molecular crosslinking. The reduced viscosities of the intra- molecular-crosslinked polymer were considerably lower than those of the linear polymer over the polymer concentration range studied, and the increase in the reduced viscosity usually observed at lower concentrations was very slight in the case of intramolecular-crosslinked polymer. The values of pH of the intra- molecular-crosslinked polymer were higher than those of the linear polymer. The present study confirms the conclusion in the previous paper that the crosslinking of polyelectrolyte in aqueous solutions can be explained only in terms of both the change in expansion and the repulsion due to ionized groups. (auth)

• Research Organization: Kyoto Univ.
• NSA Number: NSA-17-027903
• OSTI ID: 4703893
• Journal Information: Bulletin of the Institute for Chemical Research, Kyoto University (Japan), Journal Name: Bulletin of the Institute for Chemical Research, Kyoto University (Japan); ISSN BICRA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ACIDITY
ACRYLIC ACID
CROSS-LINKING
EXPANSION
GAMMA SOURCES
IONS
IRRADIATION
METALS, CERAMICS, AND OTHER MATERIALS
POLYMERIZATION
POLYMERS
RADIATION EFFECTS
SODIUM CHLORIDES
SOLUTIONS
VISCOSITY