2007 International Nuclear Atlantic Conference - INAC 2007 Santos, SP, Brazil, September 30 to October 5, 2007 ASSOCIAÇÃO BRASILEIRA DE ENERGIA NUCLEAR - ABEN ISBN: 978-85-99141-02-1 PRELIMINARY STUDY OF STYRENE GRAFTING ON POLYETHYLENE FILMS Gilberto de O. Moraes, Adriana N. Geraldes, Heloísa A. Zen, Duclerc F. Parra, Ademar B. Lugão Instituto de Pesquisas Energéticas e Nucleares (IPEN / CNEN - SP), Centro de Química e Meio Ambiente (CQMA), Av Professor Lineu Prestes, 2242, 05508-900 São Paulo, SP gibamaclarenn@hotmail.com ABSTRACT Grafting of styrene on polyethylene was carried out as a preliminary study. The experiments covered a range from 5 to 20 kGy and intended to evaluate the absorbed dose that led to the best degree of grafting (DOG) under industrial dose rate. PE films 0,065 mm thick were exposed several times to radiation at room temperature and nitrogen atmosphere. The films were immersed in the solution content styrene/solvent then irradiated (5 to 20 kGy) dose. As an exploratory experiment, styrene grafting was gravimetrically evaluated and characterized by infrared spectroscopy (FTIR).The degree of grafting ( DOG) was calculated. Concentrations of methanol/ Styrene at the rate of 80:20 were favorable at low dose of 10 kGy. In presence of acid, best result was achieved at 15 kGy in the range of 5 to 20 kGy. 1. INTRODUCTION Polyethylene (low and high density) is nowadays a very used semi-crystalline polymer, one of major commodities with large number of applications [1]. A number of techniques can be used to modify a polymer. The radiation-induced technique is known as an efficient and clean one due to absence of undesired by-products, possibility of room temperature processing and faster as well as easier management. Radiation effects on polymer properties present information valuable for investigation of molecular structure and transport process. Data on radiation effects upon properties like density, crystallinity degree and grafting degree are important in this work thanks to the large difference between effects on crystalline and amorphous phases. Such differences are important to the grafting  [2, 3 and 4]. This work aims to evaluate the patterns of grafting of styrene onto low density polyethylene (LDPE) using gamma radiation from a 60 Co source in order to synthesize an ion exchange membrane, using the simultaneous method that consists in radiation of the polymer in presence of the monomer to be grafted (irradiating film + monomer + additive + solvent), with doses and radiation times compatible with industrial procedure.