The liquid benzoxazine monomer was characterized by 1 HNMR and FTIR spectroscopy. Curing characteristics at different temperatures were studied and monitored by differential scanning calorimeter (DSC). The appearance of two exothermic peaks associated with reaction of double bonds of the aliphatic side–chain and ring opening polymerization of benzoxazine. High thermal stability of the polymer sample was confirmed by thermogravimetric analysis (TGA). | Journal of Science and Technology 55 (1B) (2017) 160–168 SYNTHESIS AND CHARACTERIZATION OF MONOFUNCTIONAL BENZOXAZINE FROM CARDANOL Cao Xuan Viet1, *, Nguyen Hoang Trinh1, Du Ngoc Uy Lan2, Tsutomu Takeichi3 1 Department of Polymer Materials, Faculty of Materials Technology, HCMUT–VNUHCM 268 Ly Thuong Kiet Street, Ward 14, District 10, Ho Chi Minh City, Vietnam 2 School of Material Engineering, Kompleks Pusat Pengajian UniMAP, Taman Muhibbah, University Malaysia Perlis, 02600 Jejawi, Arau, Perlis, Malaysia 3 Department of Environmental and Life Sciences, Toyohashi University of Technology, Tempaku–cho, 1–1 Hibarigaoka, Tempaku, Toyohashi, Aichi, 441–8580, Japan * Email: caoxuanviet@ Received: 30 December 2016; Accepted for publication: 3 March 2017 ABSTRACT A novel thermoplastic polybenzoxazine was synthesized based on agrochemical renewable cardanol–a by–product of cashew nut shell liquid (CNSL). A solventless synthesis of monofunctional benzoxazine monomer based on cardanol, aniline and paraformaldehyde was carried out. The liquid benzoxazine monomer was characterized by 1HNMR and FTIR spectroscopy. Curing characteristics at different temperatures were studied and monitored by differential scanning calorimeter (DSC). The appearance of two exothermic peaks associated with reaction of double bonds of the aliphatic side–chain and ring opening polymerization of benzoxazine. High thermal stability of the polymer sample was confirmed by thermogravimetric analysis (TGA). Keywords: benzoxazine, cardanol, cashew nut shell liquid, ring–opening polymerization. 1. INTRODUCTION Polybenzoxazines (PBzs) appeared as attractive candidates over traditional phenolic polymers due to their superior properties. These include higher thermal stability, char yield, superior modulus properties, low water absorption, near zero volumetric shrinkage, and no release of byproducts during its thermal ring–opening polymerization. Another advantages of this polymer is the .