Journal of Alloys and Compounds 449 (2008) 184–187 Surface modification of glass epoxy resin using the photocatalytic reaction in TiO 2 dispersed solution Gyung Guk Kim a , Joung Ah Kang a , Sun-Jae Kim b , Seung Han Shin c , Seon Jin Kim a,∗ a Division of Materials Science and Engineering, Hanyang University, Seoul 133-791, Republic of Korea b Advanced Materials Engineering, Sejong University, Seoul 143-747, Republic of Korea c Korea Institute of Industrial Technology, Incheon 406-130, Republic of Korea Received 4 November 2005; received in revised form 9 January 2006; accepted 20 January 2006 Available online 23 January 2007 Abstract For the surface modification of polymer, wet-chemical pretreatments using a strong acid such as chromic, sulfuric and potassium-permanganate acid have been performed. However, these methods tend to have inherent problems of uniformity, reproducibility for plating products as well as, the environmental pollution caused by using a strong acid solution. Therefore, to replace wet-chemical pretreatment process, we investigated the surface modification of glass epoxy resin using the photocatalytic reaction in TiO 2 dispersed solution. Adhesion strength was improved more than twice when in 0.01 g/L TiO 2 dispersed solution than when only UV light irradiated in the absence of TiO 2 , and XPS results revealed that the oxidized species were more activated by photocatalytic reaction. The surface modification using the photocatalytic reaction did not almost change the surface morphology. From these results, a possibility for the surface modification of glass epoxy resin using the photocatalytic reaction was confirmed. © 2006 Elsevier B.V. All rights reserved. Keywords: Glass epoxy resin; Photocatalytic reaction; Surface modification; Electroless Cu plating 1. Introduction Metallization of polymers and polymer-based materials is increasingly required in a large variety of technological appli- cations ranging from the fabrication of printed circuit boards to decorative coating in general manufacturing [1–3]. For such applications, polymer substrates are commonly metallized by the electroless plating process, which typically involves sur- face modifications to improve adhesion and surface seeding of an electroless catalyst. One of the conventional methods of surface modification is the wet-chemical pretreatment process using a strong acid such as chromic, sulfuric and potassium- permanganate acid. However, this process has inherent problems of uniformity and reproducibility for plating products. As well as, it results in undesirably environmental pollution due to being pretreated polymer materials in the strong acidic solution. ∗ Corresponding author. E-mail address: alloylab@hanyang.ac.kr (S.J. Kim). Photocatalytic process, one of the advanced oxidation pro- cesses, is receiving gradually attention due to the high chemical stability, the low cost and the possibility of using sunlight as the source of irradiation. The process is initiated upon UV irradi- ation of the photocatalyst with the formation of high energy electron/hole pairs by exciting an electron from the valence band to the conduction band. In this photocatalytic reaction, the photogenerated holes with water molecules and hydroxyl ions adsorbed on the surface of the photocatalyst yields the formation of hydroxyl radicals. The resulting hydroxyl radi- cals as very strong oxidizing agents can oxidize most of the organic compounds and form the activated oxygen species such as C O, OH and COOH [4–7]. In addition, these activated oxygen species are able to induce the hydrophile property which contributes to improve the adhesion strength of the electroless deposited film on the polymer surface [8]. So, the photocatalytic reaction may be used to oxidatively modify the polymer sur- faces without environmental pollution. In the present study, the surface modification using the photocatalytic reaction in TiO 2 0925-8388/$ – see front matter © 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.jallcom.2006.01.139