1 ST INTERNATIONAL CONFERENCE ON NATURAL FIBERS 1 ST ICNF – Future Materials for Advance Applications 1 CHARACTERIZATION OF NATURAL CORK AGGLOMERATE FUNCTIONALISED BY PLASMA TREATMENT E. A. A. Silva, F. R. Oliveira, S. N. Carmo, F. Steffens and A. P. Souto (*) Department of Textile Engineering, University of Minho, Guimarães, Portugal (*) souto@det.uminho.pt ABSTRACT This work intends to study the chemical and physical modifications of natural cork agglomerate after plasma treatment using dielectric barrier discharge (DBD). Different experimental techniques were used to evaluate the surface alterations of the substrate pre- treated with DBD plasma, namely, static and dynamic contact angle, surface energy, energy dispersive spectroscopy (EDS), scanning electronic microscopy and differential scanning calorimetry. Plasma discharge greatly increases the wettability and surface energy of the samples. Chemical and physical analyses of the cork agglomerate confirmed considerable surface modification. INTRODUCTION Over the last decades several different materials and technologies have been widely used to new applications. The number and volume of composite materials have grown steadily, penetrating and conquering new areas of engineering. In fact, everyday modern composite products are created to be applied in sophisticated niche markets. Cork is a natural material with an immense potential to be used in different applications, such as: cork stoppers, fishing rods and floats, buildings, military, footwear, automobile industries among others (Pereira, 1998). Portugal is the world's largest manufacturer of cork, been responsible alone, for approximately 50% of the total production of this substrate. However, cork has a low surface energy, which can be adverse for several applications. Chemical treatments to change the surface properties of different materials have been sometimes successful in improving the interfacial bonding (Oliveira, 2012). Nevertheless, problems related to the high cost of the treatment, the disposal of the chemical products in addition with increasing concern about environmental pollution has limited extensive industrial application of chemical surface treatments (Yoldas, 2010). Plasma technology is considered as a dry and clean process with an enormous potential environmental (Carneiro, 2001; Oliveira 2012) to modify the surface of several materials without affect its bulk properties. In plasma processing, it is well established that exposure to plasmas generated in inert and reactive gases can clean the surface of materials and change their properties, particularly their surface energy (Oliveira, 2013). This work presents a study of plasma treatment of agglomerate cork, using a dielectric barrier discharge (DBD) run in different dosages. The experiments were conducted to determine the effects of the plasma treatments on the measured changes to surface, wettability, morphology and chemical composition.