Micro sized gels have been widely used as drug carriers for its compatibility in blood. Among its important properties are round small dimensions and large surface area. These properties allow for better attachment of ligand and higher stability in the blood stream. In this study,microgels from polyethylene glycol diacrylate (PEGDA) were prepared from its microemulsions form using electron beam with energy of 3 MeVat different irradiation dose of 0 to 25 kGy. Dynamic light scattering (DLS) study revealed that gel with diameter of 70-100 nm with a narrow size distribution was obtained at 5 kGy and 400-550 nm with a broad size distribution at 25 kGy. The molecular weight obtained from GPC-MALLS for the minimum practical dose irradiated has resulted to more than 4.22 x 105 g/mol as compared to7.75 x 102 g/mol forunirradiated polymer. The increase of size and its distribution as well as its molecular weight over the elevation dose were suspected to be due to diffusion of micelles that leads to recombination of macro radicals from different micelles during longer irradiation period at higher doses. Overall findings from this study have proven that PEGDA microgels can be prepared via electron beam radiation with emulsions as templates for polymerization.

This paper presents results from a series of experiments in which two combinations of polymer-dye film were exposed to ionizing radiation (electron beam). These experiments were performed for the purpose of investigating the possibility of polyethylene (PE) and polyvinyl chloride (PVC) with and without the addition of malachite green (MG) dye for radiation indication in the form of colour transition. MG dye was also inspected whether it has experienced the photodarkening from the exposure to ionizing radiation. The experiments were carried out using samples in the form of film. From this study, it was proven that the polymers and dye do not work alone to give the change. Halogen-containing polymer was found positive in stimulating the acid-sensitive dye for the transition of colour. The colour transition of the combination of PVC/MG without pH adjustment was consistently increasing with irradiation level. The transition is observed even at 100 kGy of the radiation exposure. Samples with the addition of basic solution have a rapid change in terms of colour but the limit of sensitivity was decreased to only 20 kGy of radiation exposure.