Oxidative degradation of poly(vinyl chloride). [25/sup 0/C;. gamma. -initiated]

Journal Article · Wed Dec 01 00:00:00 EST 1976 · J. Appl. Polym. Sci.; (United States)

DOI:https://doi.org/10.1002/app.1976.070201213· OSTI ID:7313005

Decker, C

Rates of oxygen consumption and formation of oxidation products were determined in ..gamma..-initiated oxidation of poly(vinyl chloride) (PVC) at 25/sup 0/C. Data are given for five dose rates and correlated on the basis that the overall oxidation is the sum of two reactions that are first order and half order in rate of initiation. The principle oxidation product is hydroperoxide, formed by the half-order reaction, whereas alcohol and carbonyl compounds result mostly from first-order reactions. These products account for 77 to 80 percent of the total oxygen absorption. The presence of oxygen was found to increase twofold the rate of dehydrochlorination of irradiated PVC. A reaction scheme is developed which assumes that a significant fraction of the interactions of tertiary peroxy radicals is nonterminating and yields alkoxy radicals which propagate or decompose by ..beta..-scission. This decomposition occurs mostly by splitting off a chlorine atom with formation of a ketone and, to a lesser extent, by C--C cleavage which accounts for the observed decrease in molecular weight of the oxidized PVC. Polystyrene was found to be much more resistant to oxidation than PVC. A classification of some commercial polymers in function of their susceptibility to oxidation is proposed.

• Research Organization: Centre de Recherches sur les Macromolecules, Strasbourg
• OSTI ID: 7313005
• Journal Information: J. Appl. Polym. Sci.; (United States), Vol. 20:12
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
36 MATERIALS SCIENCE
POLYSTYRENE
CHEMICAL RADIATION EFFECTS
PVC
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
COMPARATIVE EVALUATIONS
DECOMPOSITION
DOSE RATES
GAMMA RADIATION
MEDIUM TEMPERATURE
OXIDATION
CHEMICAL REACTIONS
CHEMISTRY
CHLORINATED ALIPHATIC HYDROCARBONS
ELECTROMAGNETIC RADIATION
HALOGENATED ALIPHATIC HYDROCARBONS
IONIZING RADIATIONS
KINETICS
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC POLYMERS
PETROCHEMICALS
PETROLEUM PRODUCTS
PLASTICS
POLYMERS
POLYOLEFINS
POLYVINYLS
RADIATION CHEMISTRY
RADIATION EFFECTS
RADIATIONS
REACTION KINETICS
YIELDS
400600* - Radiation Chemistry
360405 - Materials- Polymers & Plastics- Degradation & Erosion- (-1987)