Investigation on Electron Absorbed Dose in a Mixture of Natural Rubber Latex and Cross-linking Agents

• Published in: Journal of physics. Conference series 2018-12, Vol.1144 (1), p.12117
• Main Authors: Nanthanasit, P, Jaikaew, P, Kongmon, E, Rimjaem, S
• Format: Article
• Language: English
• Subjects: Accelerators; Air gaps; Crosslinking; Electron accelerators; Electron beams; Electron energy; Electron irradiation; Ethylene glycol; Glycol dimethacrylates; Latex; Metal foils; Natural rubber; Radio frequency; Research facilities; Rubber products; Simulation; Titanium; Vulcanization
• ISSN: 1742-6588; 1742-6596
• DOI: 10.1088/1742-6596/1144/1/012117

Natural rubber vulcanization using electron beam is one of interesting applications of electron accelerators with an energy in a range of a few hundred keV to a few MeV. At the Plasma and Beam Physics (PBP) Research Facility, Chiang Mai University, a 4-MeV radio-frequency (RF) linear accelerator is developed for utilizing in natural rubber vulcanization. To accelerate the vulcanization process, cross-linking agents are added in a natural rubber latex to increase the bonding probability between the chains of rubber molecules. This research used a Monte Carlo based program GEANT4 to simulate the electron absorbed dose in a mixture of natural rubber latex and cross-linking agents. The initial electron energy distributions were obtained from the beam dynamic simulation in the accelerator, which were done with program ASTRA. The initial electron beams have average energy in the range of 0.70 to 4.02 MeV at the position 6 cm prior the 50μm titanium vacuum window foil. The air gap between the vacuum window to the natural rubber latex was set at 18 cm. The electron beam transportation in the titanium foil, air gap and a mixture of natural rubber latex were simulated. The cross-linking agents that are added in the natural rubber latex are ethylene glycol dimethacrylate (EDMA) and 1,6-hexanediol-diacrylate (HDDA). Finally, electron absorbed dose distributions in both transverse direction and along the depth of the natural rubber latex mixed with each cross-linking agent were calculated and analyzed. The results from this work can be used for experimental planning of electron beam irradiation on the natural rubber latex with appropriate cross-linking agents and electron absorbed dose.