Polyoxazoline associated with cardanol for bio‐based linear alkyl benzene surfactants

Abstract

Well‐defined linear alkyl benzene surfactants (COxn) were successfully synthesized using cardanol as a green phenolic alternative and initiator for polyoxazoline (POx), the hydrophilic block of nonionic surfactants. Various hydrophilic lipophilic balance values were investigated by varying the POx length according to the [monomer]/[initiator] ratio. The chemical structure of the surfactants, in particular the terminal groups, was well identified by matrix assisted laser desorption ionization time of flight mass spectrometry demonstrating the good progress of the cationic ring‐opening polymerization. The COxn surfactants spontaneously self‐assembled in water at a critical aggregation concentration of 1–2 µmol L−1 into nano‐objects characterized by a hydrodynamic diameter of 11–24 nm and a number of aggregations ranging from 30 to 60 according to the worm‐like micelle model. © 2019 Society of Chemical Industry

Development of Sustainable Chemistry in Madagascar: Example of the Valuation of CNSL and the Use of Chromones as an Attractant for Mosquitoes

“…Comparison of the repellent effect of R-(−)-7-sec-butoxychromone (14) with those of known repellents at equivalent quantities 5, 10, and 30 mg shows that this new repellent is more effective than picaridin and DEET, which are considered to be the most effective products on the market (Table 17). The mean activity of mosquitoes during testing of the three compounds, racemic 7-secpentoxychromone (11), R-(−)-7-sec-pentoxychromone (16), and S-(+)-7-sec-pentoxychromone (17), was >85%. Average numbers of mosquitoes recorded in the control zone were significantly lower than those of the treated zone (p-values < 0.05) except for the 30 mg of the two enantiomers R( 16) and S-(+)-7-sec-pentoxychromone (17) (p-values > 0.05) where the mean of mosquitoes in the control was statistically similar to that of treated (Table 18).…”

“…Beyond this quantity, there was a clear decrease of the attractant effect as recorded for 30 mg. In general, racemic (11) and R-(−)-7-secpentoxychromone ( 16) had a better attractive activity than S-(+)-7-sec-pentoxychromone (17). Maximum attractant effect was around 63% at the quantity 10 mg of R enantiomer compound (Figure 6).…”

“…In this study, we have three chromones derivatives repellents represented by racemic 7-sec-butoxychromone (10), R-(−)-7-sec-butoxychromone (14), and S-(+)-7-sec-butoxychromone (15). Conversely, there are five attractants: racemic 7-sec-pentoxychromone (11), R-(−)-7-sec-pentoxychromone ( 16), S-(+)-7-sec-pentoxychromone (17), 7-sec-nonyloxychromone (12), and 7-(2 -ethyl)hexyloxychromone (13).…”

“…T-test comparison of the average numbers of mosquitoes in the two zones: control and treated with racemic 7-sec-pentoxychromone (11), R-(−)-7-sec-pentoxychromone (16), and S-(+)-7-sec-pentoxychromone (17). Racemic 7-sec-pentoxychromone (11) and its enantiomers have attractive effects on Aedes albopictus. This attractive activity was observed for all quantities but there was an optimal quantity to have a maximum attractant effect.…”

“…The crude CNSL consists mainly of anacardic acid (1) (65%) cardol (2) (20%), and cardanol (3) (10%), [6,7]. Several types of surfactants have already been synthesized from its constituents: polyethoxylates, sulfonates, and carboxylates [8][9][10][11]. In most of the cases, these products are obtained through a multistep synthesis and after tedious and expansive separation of the mixture.…”