Present status of 4 MeV electron beam accelerator system for natural rubber irradiation

Electron beam accelerator system for natural rubber irradiation is under developing at the Plasma and Beam Physics (PBP) Research Facility, Chiang Mai University (CMU). The system aims to improve the natural rubber latex properties by using energetic electrons to induce cross-linking between polymer chain or called vulcanization process. Due to no chemical added as a conventional way (usually sulphur), the rubber product produced by this method has good mechanical properties with lower toxicity that is suitable for many applications. The system consists of a DC thermionic cathode electron gun, a 5-cell radio-frequency (RF) linear accelerator (linac), an RF modulator, an adjustable speed conveyer and a control system. The expected electron beam energy from the simulation is in the range from 0.5 to 4 MeV with a maximum pulse current of 100 mA and a pulse repetition rate is adjustable from 20 to 400 Hz. This beam condition provides a calculated average absorbed dose between 160 and 640 Gy. The system has been complete assembled and the RF modulator has been tested. The RF processing has been performed and some of electron beam properties has been measured. The present status of development and the results are reported in this contribution. (paper)