Anionic Surfactants Synthesised from Replenishable Phenolic Lipids

Abstract

The oligomers (m = 1,2,3,4 and 5) in the profile of compounds obtained in the ethoxylation of saturated cardanol with ethylene oxide have been synthesised. The first member which occurs only in traces in the reaction has now been synthesised by an improved method. This monoethoxylate of 3-pentadecylphenol and a diethoxylate of 5-pentadecylresorcinol (2-hydroxyethyl derivatives) have been synthesised by the base-catalysed reaction with ethylene carbonate. Cardanol and cardol separated from technical cashew nut-shell liquid (CNSL) have been similarly reacted as have saturated cardanol and saturated cardol obtained by reduction of the side-chain. Reaction of the anhydrous potassium salt of 3-pentadecylphenol in dichloromethane with ethylene sulfate has afforded a derivatives having a sulfate group in place of the terminal hydroxyl group and avoiding the use of sulfuric acid. Similarly CNSL and saturated CNSL reacted with ethylene sulfate gave sulfo derivatives which possess excellent surfactancy. By contrast, with sulfuric acid, 3-pentadecyl phenol monoethoxylate gave a trisulfo product comprising a terminal side-chain sulfate and a ring disulfonic acid. 3-Pentadecylphenol reacted with sulfuric acid in carbon tetrachloride to give 4-hydroxy-6-pentadecylphenol-1,3-disulfonic acid.

Functionalization of cardanol: towards biobased polymers and additives

“…[146][147][148] It has been demonstrated that CNSL and saturated CNSL upon reaction with ethylene sulfate give sulfo derivatives which possess excellent surfactant properties. 149 The use of ethylene sulfate with the phenoxide is an improvement which avoids both the reaction with sulfuric acid and the need for an initial hydroxyethylation step. In recent years, several amphiphilic molecules based on cardanol have been investigated and found to be potentially useful for many industrial applications (Fig.…”

Cardanol: A promising building block for biobased polymers and additives

“…[83][84][85] It is reported that saturated cardanol is readily sulfonated with excess sulfuric acid in halogenated solvents at ambient temperature (Figure 2, S3-S4). [86][87][88][102][103][104] It has been demonstrated that CNSL and saturated CNSL upon reaction with ethylene sulfate gave sulfo derivatives which possess excellent surfactant properties. [89] The use of ethylene sulfate with the phenoxide is an improvement which avoids both the reaction with sulfuric acid and the need for an initial hydroxyethylation step.…”

Development of novel pH-sensitive azo dyes from Cardanol as a bioresource

“…The chemical structure of the cardanol is shown in Scheme 1, which is extensively used in the development of stabilizers (Kirschweng et al , 2017), plasticizers (Chen et al , 2016) and laminates and for insulation purposes (Balgude and Sabnis, 2014). This compound can undergo various electrophilic substitution reactions like other phenolic compounds including halogenation (Attanasi et al , 2006; Voirin et al , 2014), sulfonation (Bruce et al , 2009) and nitration (Lubi and Thachil, 2000) and also the other reactions of the hydroxyl functional group alike epoxidation and esterification (Chen et al , 2015; Thenmozhi and Murugavel, 2019). Furthermore, the use of naphthalene derivatives as a diazotization or coupling compounds is known for decades which covers the huge number of industrially important azo dyes (Mohammadi and Ghafoori, 2015; “Naphthalene Derivatives”, 2006; Rasheed, 2011).…”