[en] Research on radiation processing of natural polymer such as polysaccharides of chitosan, cellulose, carrageenan has been carried out in Sri Lanka since the year 2004. The research group have been involving in development activities on application of chitin and chitosan for wound dressing, irradiated chitosan on shelf life extension of fruits such as papaya, banana, mangoes, radiation crosslinked super-absorbent hydrogel from sodium carboxymethyl cellulose by radiation processing. Hydrogels prepared with PVA/Carrageenan/Agar has been studied on guinea pigs to determine the wound healing effect. Irradiated chitosan powder and chitosan solution was studied in vitro and found chitosan solution (1%) directly subjected to irradiation dosages even at 5 kGy was highly effective in control of anthracnose causing organism of papaya. In vivo studies with irradiated 1% chitosan solution on Rathana and red lady variety of papaya shows better control of spoilage of papaya to a considerable extent. The government of Sri Lanka (Ministry of Science and Technology and Atomic Energy Authority) is in the process of establishing the first government owned Multipurpose Gamma Irradiation Facility and it will be helpful to transfer the output of R and D in radiation processing. (author)

[en] There is a bright future for radiation vulcanised natural rubber latex (RVNRL) but there are problems in manufacturing it as the centrifuged latex to be used for radiation has to be kept for at least a month or sometimes even three to six months before adding the sensitisers and even then the latex sometimes coagulates on adding the sensitisers. This paper describes a process by which the latex can be stabilised by addition of an anionic soap before centrifuging so that it has a high mechanical stability and hence can be used even within one week of the manufacture of the centrifuged latex

[en] Radiation vulcanization of natural rubber latex (RVNRL) can be used to make large quantities of specially stabilized latex. It is possible to obtain RVNRL films of tensile strength over 25 MPa. The films could be either coagulant dipped or cast. It is very important to determine the correct radiation dose which gives the maximum tensile strength. Cross linking density or prevulcanized relax modulus (PRM) at 100% is a reliable property to control the prevulcanization