PLASTIFICATION OF POLYETHYLENE BY LOW-TEMPERATURE RADIOLYSIS

Journal Article · Fri Dec 21 04:00:00 EST 1962 · Doklady Akad. Nauk SSSR

OSTI ID:4718139

Nikol'skii, V G; Buben, N Ya

High-pressure polyethyiene disks 10 mm in diameter and 2 mm thick were irradiated at a temperature of 77 deg K with fast electrons at doses of 1 to 70 million rads. The samples were heated at a constant rate, and the luminescence due to the recombination of active centers formed by the irradiation was recorded by a photomultiplier. The luminescence maximum at 233 deg K, which corresponds to the transition of polyethylene to an elastically plastic state, decreased from 230 deg K at a dose of 1 x 10/sup 6/ rads to about 190 deg K at a dose of 70 x 16/ sup 6/ rads. A sample irradiated with a dose of 20 x 18/sup 6/ rads at 77 deg K was heated to 300 deg K, and then cooled to 77 deg K and reirradiated with a dose of 1 x 10/sup 6/ rads. The resulting luminescent curve was similar to that obtained with a sample irradiated at 17 deg K with a dose of 1 x 10/sup 6/ rads. The plastification of the polyethyiene was due to the formation of hydrogen and other low-molecular-weight hydrolysis products (hydrocarbons). If the heating rate on thin, irradiated polyethylene samples was decreased from 40 to 50 deg per minute to 5 deg per minute, no difference in melting points couid be observed for samples given doses of 0.5 and 4 million rads respectively. With the low- temperature irradiation of polyethylene, cross-linking reactions tended to raise the melting point, but the gaseous radiolytic products tended to decrease the melting point. (TTT)

• Research Organization: Inst. of Physics and Chemistry, Academy of Sciences, USSR
• NSA Number: NSA-17-010688
• OSTI ID: 4718139
• Journal Information: Doklady Akad. Nauk SSSR, Journal Name: Doklady Akad. Nauk SSSR Vol. Vol: 147
• Country of Publication: Country unknown/Code not available
• Language: Russian

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CHEMISTRY