IRRADIATION GRAFTING OF STYRENE TO HIGH PRESSURE AND LOW PRESSURE POLYETHYLENE FILMS

Journal Article · Thu Jan 01 04:00:00 EST 1959 · J. Polymer Sci.

DOI:https://doi.org/10.1002/pol.1959.1203412734· OSTI ID:4273424

Hoffman, A S; Gilliland, E R; Merrill, E W; Stockmayer, W H

The cobalt-60 ganama irradiation of high pressure and low pressure (Marlex-50) polyethylene films immersed in styrene monomer to produce graft polymers was studied as a function of dose, temperature, and film thickness. It was found that grafting generally increased with dose, but reached a level for all films at 10 to 20 C and an average dose rate of 228,000 rad/hr, where the grafting was higher for the thinnest films (1.5 to 2 mils) than the thicker films (up to 20 mils). At 40 and 70 C and an average dose rate of 93,500 rad/hr, the grafting increased approximately linearly with dose for all films. The post- effects were also studied and found to be more significant for higher film thickness, higher polymer crystallinities, and lower temperatures. Obsevations of the heterogeneity found in the grafted films were described, photos were shown, and these effects were discussed. It was concluded that for the dose rates employed, grafting was probably diIfusioncontrolled for all films at 10 to 20 C and perhaps for the thicker films at 40 C. The effects of changes in the various fndependent and dependent variables on the grafting mechanism were discussed and a qualitative picture of this mechanism was described. It was then concluded that the different polycrystalline natures and different thicknesses of the films (as they affected the monomer diffusion rate), and the dose rate or rate of initiation of free radicals were among the most important factors in determining the mechanism and resultant efficiency of grafting. (auth)

• Research Organization: Massachusetts Inst. of Tech., Cambridge
• NSA Number: NSA-13-009824
• OSTI ID: 4273424
• Journal Information: J. Polymer Sci., Journal Name: J. Polymer Sci. Vol. Vol: 34
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

CHEMICAL REACTIONS
CHEMISTRY
COBALT 60
CRYSTALS
DIFFUSION
FILMS
FREE RADICALS
GAMMA RADIATION
PHOTOGRAPHY
POLYETHYLENES
PRESSURE
RADIATION CHEMISTRY
RADIATION DOSES
RADIATION EFFECTS
REACTION KINETICS
STYRENE
TEMPERATURE
THICKNESS