RADIATION PROTECTION OF AQUEOUS POLYVINYLPYRROLIDONE SOLUTIONS BY THIOUREA

Journal Article · Thu Aug 01 04:00:00 EDT 1963 · Intern. J. Radiation Biol.

DOI:https://doi.org/10.1080/09553006314551031· OSTI ID:4013688

Kopp, P M; Charlesby, A

A detailed study was made of radiation protection effects in -a model macromolecular system --- polyvinylpyrrolidone in water, with thiourea acting as the protecting additive. The effects of polymer concertration, dose-rate and additive concentration on the gelation dose were determined. In the absence of polymer, dilute thiourea solutions show rapid destruction of thiourea on irradiation, with a smaller reduction in its subsequent protective ability. It is concluded that the major form of protection is offered by thiourea against the indirect effect of radicals produced in the water. Further protection occurs by H-transfer to polymer radicals; these constitute true protection, and the polymer is unaltered. Furthermore, thiourea can be linked into polymer giving a modified stabilized product. The great ability of thiourea to protect, even at very low concentrations, is ascribed to the thiol-thione equilibrium in solution, which allows a chain reaction form of protection. This was confirmed in a range of other additives. (auth)

• Research Organization: Royal Military Coll. of Science, Swindon, Eng.
• Sponsoring Organization: USDOE
• NSA Number: NSA-18-020056
• OSTI ID: 4013688
• Journal Information: Intern. J. Radiation Biol., Journal Name: Intern. J. Radiation Biol. Vol. Vol: 7
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ADDITIVES
CHEMISTRY
COLLOIDS
EXPANSION
GELATION
ORGANIC NITROGEN COMPOUNDS
ORGANIC SULFUR COMPOUNDS
POLYVINYLS
PVP
PYRROLIDONES
RADIATION DOSES
RADIATION PROTECTION
REACTION KINETICS
SOLUTIONS
UREA
WATER