Effect of a Coupling Agent on the Electromagnetic and Mechanical Properties of Carbon Black/Acrylonitrile–Butadiene–Styrene Composites Yuping Duan, Shunhua Liu, 1 Guiqin Wang, 1 Hongtao Guan, 1 Bin Wen 1 1 School of Materials Engineering, Dalian University of Technology, Dalian 116023, People’s Republic of China Received 27 July 2005; accepted 26 December 2005 DOI 10.1002/app.24014 Published online in Wiley InterScience (www.interscience.wiley.com). ABSTRACT: Titanate coupling agent (TCA) is widely used as a plasticizer in filled polymer processes. In this study, the effect of TCA with different contents (2 and 10 wt %) on the electrical conductivity, wave absorption, and me- chanical properties of carbon black (CB)/acrylonitrile– buta- diene–styrene (ABS) composites were investigated. The re- sults indicate that with the addition of 2 wt % TCA to the filled CB, the electrical conductivity of CB/ABS composites improved greatly, but its wave absorption performance was weakened. In contrast, the addition of 10 wt % TCA to the filled CB improved the microwave absorption performance of the CB/ABS composites but led to poor electrical conduc- tivity. However, TCA, regardless of the contents of 2 or 10 wt %, greatly improved the mechanical properties of the composites. The probable reasons for this are discussed on the basis of the fracture morphology of the sample, a chem- ical band between the filling and resin, and the physical coating between the filling and TCA. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1839 –1843, 2006 Key words: additives; composites; conducting polymers; mechanical properties; particle size distribution INTRODUCTION Carbon black (CB) is widely used as the main rein- forcement filler for high-performance composite ma- terials. These materials have various useful properties, including corrosion resistance, low density, thermal expansion, electrical conductivity, and wave absorp- tion. 1,2 So they are attractive substitutes for various metal, alloys, and other materials. They offer versatile applications in the fields of aerospace, batteries, solar cells, resistors, semiconductor elements, antistatics and electromagnetic shielding, and absorption mate- rials. 3–6 The properties of a composite, such as the strength and modulus, are important factors in the production of high-quality composites. The properties of the filler and matrix make a critical contribution to the quality of a polymer composite. In addition, the physicochem- ical interaction at the filler–matrix interface plays an important role in improving the mechanical properties of a polymer composite. Many researchers have tried to improve the adhesion between fillers (e.g., CB, car- bon fiber, metal powder) and matrix resins by chem- ical reactions with a coupling agent. 3,7 An additional coupling agent in a polymer compos- ite may not only improve its mechanical properties but may also improve its electrical conductivity and electromagnetic characteristics. 8 In this article, we re- port the influence of a titanate coupling agent (TCA) on the mechanical properties, electrical conductivity, and microwave properties of CB-filled acrylonitrile– butadiene–styrene (ABS); the probable reasons for the results are discussed on the basis of the fracture mor- phology of the sample, a chemical band between the filling and resin, and the physical coating between the filling and TCA. EXPERIMENTAL The basic components in the objects investigated were composed of ABS CH510 (Panjin Ethylene Industry Co., China), acetylene CB N234 (FuShun DongXin Chemical Co., Ltd., China), and TCA NDZ-105 (Wu- Han HuaChang Application Technology Institute, China) To get rid of the oxygenous group and to activate CB, CB was heat-treated at 700°C for 30 min in flowing argon. At the same time, TCA was diluted with iso- propyl alcohol (35 wt % of the TCA), and the treated CB was immersed in its solution subsequently; we stirred the intermixture adequately. At last, the CB treated with the TCA was dried at 100°C. The contents of the TCA in CB was 2 and 10 wt %, respectively. ABS was heat-treated at 100°C for 120 min in air; the water Correspondence to: Y. P. Duan (dypingg@sohu.com). Contract grant sponsor: National Natural Science Foun- dation of China; contract grant number: 50402025. Journal of Applied Polymer Science, Vol. 102, 1839 –1843 (2006) © 2006 Wiley Periodicals, Inc.