Jadhav Nilesh L, Sastry Sai Krishna C, Pinjari Dipak V
Department of Chemical Engineering, Institute of Chemical Technology, N.P. Marg, Matunga, Mumbai 400 019, India.
Department of Chemical Engineering, Institute of Chemical Technology, N.P. Marg, Matunga, Mumbai 400 019, India.
Ultrason Sonochem. 2018 Apr;42:532-540. doi: 10.1016/j.ultsonch.2017.12.001. Epub 2017 Dec 7.
The present study deals with synthesis of cardanol-cased novolac (CBN) resin by the condensation reaction between cardanol and formaldehyde using acoustic cavitation. It is a step-growth polymerization which occurs in the presence of an acid catalyst such as adipic acid, citric acid, oxalic acid, sulphuric acid and hydrochloric acid. CBN was also synthesised by a conventional method for the sake of comparison of techniques. The effect of molar ratio, effect of catalyst, effect of different catalyst and effect of power on the conversion to CBN has been studied. The synthesised CBN was characterized using the Fourier Transform Infra Red Spectroscopy (FTIR), Gel Permeation Chromatography (GPC), Nuclear Magnetic Resonance (NMR) Spectroscopy and Thermogravimetric Analysis (TGA). The reaction was monitored by the Acid value, free formaldehyde content and viscosity of the synthesised product. The reaction time required for the conventionally synthesised CBN was 5 h (300 min) with 120 °C as an operating temperature while sonochemically the time reduced to 30 min at room temperature. The amount of time and energy saved can be quantified. Ultrasound facilitated synthesis was found to be an energy efficient and time-saving method for the synthesis of novolac resin.
本研究涉及使用声空化作用，通过腰果酚与甲醛之间的缩合反应合成腰果酚基酚醛清漆（CBN）树脂。这是一种在诸如己二酸、柠檬酸、草酸、硫酸和盐酸等酸催化剂存在下发生的逐步聚合反应。为了比较技术，还通过传统方法合成了CBN。研究了摩尔比、催化剂、不同催化剂以及功率对CBN转化率的影响。使用傅里叶变换红外光谱（FTIR）、凝胶渗透色谱（GPC）、核磁共振（NMR）光谱和热重分析（TGA）对合成的CBN进行了表征。通过合成产物的酸值、游离甲醛含量和粘度监测反应。传统方法合成CBN所需的反应时间为5小时（300分钟），操作温度为120°C，而在室温下通过声化学方法反应时间缩短至30分钟。节省的时间和能量数量可以量化。发现超声辅助合成是一种合成酚醛清漆树脂的节能且省时的方法。
