You need JavaScript to view this

Kinetics of polymer degradation in solution. 6. Laser flash photolysis and pulse radiolysis studies of polymethylvinylketone in solution using the light scattering detection method

Journal Article:

Abstract

Polymethylvinylketone (PMVK) was irradiated in solution with 2 ..mu..s pulses of 15 MeV electrons or with 15 ns flashes of 262 nm light. The change of the intensity of the light scattered by the solution (LSI) after the irradiation was measured. For the radiolysis experiments, a main chain scission process tausub(1/2) (decr) approximately 20 ..mu..s) and a subsequent crosslinking process (tausub(1/2) (incr) approximately 0.4 sec) could be discriminated. The LSI change pertaining to the main chain degradation was found to be due to disentanglement diffusion, whereas the LSI change pertaining to the crosslinking process could be correlated to a chemical reaction. The rate constant for combination of lateral macroradicals in acetone solution was estimated as 2 k/sub 2/ - (4.5 +- 1.5)10/sup 6/ M/sup -1/ sec/sup -1/. Stationary irradiation with /sup 60/Co-..gamma..-rays showed that PMVK is predominantly crosslinked to form a macrogel when irradiated in the solid state or in solution at concentrations greater than 100 g/l. At lower concentrations, microgel formation occurred. Photolysis of PMVK in solution yielded only main chain degradation. The LSI change was found to be due to disentanglement diffusion as during radiolysis. It was concluded that the same mechanism for main chain rupture is operative  More>>
Authors:
Lindenau, D; Beavan, S W; Beck, G; Schnabel, W [1] 
  1. Hahn-Meitner-Institut fuer Kernforschung Berlin G.m.b.H. (Germany, F.R.)
Publication Date:
Jan 01, 1977
Product Type:
Journal Article
Reference Number:
AIX-09-365069; EDB-78-045780
Resource Relation:
Journal Name: Everyman's Sci.; (United Kingdom); Journal Volume: 13:10
Subject:
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; POLYVINYLS; PHOTOLYSIS; RADIOLYSIS; ACETONE; CHEMICAL REACTION KINETICS; CROSS-LINKING; ELECTRONS; KETONES; MOLECULAR WEIGHT; SCATTERING; SOLUTIONS; ULTRAVIOLET RADIATION; CHEMICAL RADIATION EFFECTS; CHEMICAL REACTIONS; CHEMISTRY; DECOMPOSITION; DISPERSIONS; ELECTROMAGNETIC RADIATION; ELEMENTARY PARTICLES; FERMIONS; KINETICS; LEPTONS; MIXTURES; ORGANIC COMPOUNDS; ORGANIC POLYMERS; PHOTOCHEMICAL REACTIONS; POLYMERIZATION; POLYMERS; RADIATION CHEMISTRY; RADIATION EFFECTS; RADIATIONS; REACTION KINETICS; 400600* - Radiation Chemistry; 400500 - Photochemistry
OSTI ID:
5182844
Country of Origin:
United Kingdom
Language:
English
Other Identifying Numbers:
Journal ID: CODEN: EVSCB
Submitting Site:
INIS
Size:
Pages: 819-824
Announcement Date:

Journal Article:

Citation Formats

Lindenau, D, Beavan, S W, Beck, G, and Schnabel, W. Kinetics of polymer degradation in solution. 6. Laser flash photolysis and pulse radiolysis studies of polymethylvinylketone in solution using the light scattering detection method. United Kingdom: N. p., 1977. Web.
Lindenau, D, Beavan, S W, Beck, G, & Schnabel, W. Kinetics of polymer degradation in solution. 6. Laser flash photolysis and pulse radiolysis studies of polymethylvinylketone in solution using the light scattering detection method. United Kingdom.
Lindenau, D, Beavan, S W, Beck, G, and Schnabel, W. 1977. "Kinetics of polymer degradation in solution. 6. Laser flash photolysis and pulse radiolysis studies of polymethylvinylketone in solution using the light scattering detection method." United Kingdom.
@misc{etde_5182844,
title = {Kinetics of polymer degradation in solution. 6. Laser flash photolysis and pulse radiolysis studies of polymethylvinylketone in solution using the light scattering detection method}
author = {Lindenau, D, Beavan, S W, Beck, G, and Schnabel, W}
abstractNote = {Polymethylvinylketone (PMVK) was irradiated in solution with 2 ..mu..s pulses of 15 MeV electrons or with 15 ns flashes of 262 nm light. The change of the intensity of the light scattered by the solution (LSI) after the irradiation was measured. For the radiolysis experiments, a main chain scission process tausub(1/2) (decr) approximately 20 ..mu..s) and a subsequent crosslinking process (tausub(1/2) (incr) approximately 0.4 sec) could be discriminated. The LSI change pertaining to the main chain degradation was found to be due to disentanglement diffusion, whereas the LSI change pertaining to the crosslinking process could be correlated to a chemical reaction. The rate constant for combination of lateral macroradicals in acetone solution was estimated as 2 k/sub 2/ - (4.5 +- 1.5)10/sup 6/ M/sup -1/ sec/sup -1/. Stationary irradiation with /sup 60/Co-..gamma..-rays showed that PMVK is predominantly crosslinked to form a macrogel when irradiated in the solid state or in solution at concentrations greater than 100 g/l. At lower concentrations, microgel formation occurred. Photolysis of PMVK in solution yielded only main chain degradation. The LSI change was found to be due to disentanglement diffusion as during radiolysis. It was concluded that the same mechanism for main chain rupture is operative as in radiolysis. Stationary irradiations with uv light (lambda > 260 nm ) resulted in main chain degradation; no indication of crosslinking was obtained.}
journal = {Everyman's Sci.; (United Kingdom)}
volume = {13:10}
journal type = {AC}
place = {United Kingdom}
year = {1977}
month = {Jan}
}