Journal of Engineering Science, Vol. 15, 23–33, 2019 © Penerbit Universiti Sains Malaysia, 2019. This work is licensed under the terms of the Creative Commons Attribution (CC BY) (http://creativecommons.org/licenses/by/4.0/). Synthesis of Cardanol-Based Novolac Resin from Cashew Nut Shell Liquid Putri Rahmawati 1 , Ari Handono Ramelan 2 , Soerya Dewi Marliyana 1 , Neng Sri Suharty 1 and Sayekti Wahyuningsih 1* 1 Department of Chemistry, Faculty of Mathematic and Natural Science, Sebelas Maret University, Surakarta, Indonesia 2 Department of Physics, Faculty of Mathematic and Natural Science, Sebelas Maret University, Surakarta, Indonesia * Corresponding author: sayekti@mipa.uns.ac.id Published online: 30 April 2019 To cite this article: Putri Rahmawati, Ari Handono Ramelan, Soerya Dewi Marliyana, Neng Sri Suharty and Sayekti Wahyuningsih (2019). Synthesis of cardanol-based novolac resin from cashew nut shell liquid. Journal of Engineering Science, 15, 23–33, https://doi. org/10.21315/jes2019.15.3. To link to this article: https://doi.org/10.21315/jes2019.15.3 Abstract: Phenolic resin is a kind of polymer product obtained through several types of polymerisation process of natural or synthetic materials. One of natural compounds that can be applied for polymer manufacture is cardanol. By means of this research, cardanol has been successfully isolated from cashew nut shell liquid (CNSL) through liquid-liquid extraction methods while cardanol-based novolac resin was synthesised from obtained isolate and formaldehyde was synthesised by addition of citric acid as catalyst. Both isolated cardanol and cardanol-formaldehyde (CF)-based novolac resin were being confrmed by Fourier transform infrared (FTIR) and nuclear magnetic resonance (1H NMR). thermogravimetry-differential thermogravimetry (TG-DTA) analyser were undertaken to analyse thermal stability of the resin. Based on FTIR spectras and 1H NMR spectroscopy, CF-based novolac resin was successfully synthesised through polycondensation reaction. Thermal stability of isolated CF resin showed high degradation temperature of 282°C. Keywords: cardanol, CNSL, novolac, resin 1. INTRODUCTION Resin is one of important material that is used in several industrial felds. Several types of synthetic resin that is commonly used in industrial sectors are epoxide, polyure-thane, alkide, phenolic and silicate. But, considering health hazard, handling issues and toxicity, the use of those resins is attempted to be