Vanillin-Based Polymers—part II: Synthesis of Schiff Base Polymers of Divanillin and Their Chelation with Metal Ions

Abstract

Condensation of renewable resources-based monomer divanillin with alkyl diamines gives Schiff base polymers with degree of polymerization (DP) ∼25-32 in 88-95% yield. These yellow polymers are insoluble in water and common organic solvents, slightly soluble in warm DMSO, DMF and dissolves in aqueous NaOH. The polymers were characterized using FT-IR, 1 H, and 13 C NMR spectroscopy and by comparison with the model compound N, N -bis(vanillidene)-1,3-propanediamine. Polymer prepared by condensation of divanillin and 1,6-diaminohexane is shown to chelate with Cu(II), Fe(II), and Co(II) metal ions in basic aqueous methanol.

Renewable (semi)aromatic polyesters from symmetrical vanillin-based dimers

“…12 Vanillic acid was also used as a comonomer in the synthesis of a multitude of thermotropic polymers, which exhibit liquid crystal formation in the melt form. 32,33 Divanillin was classically synthesized by oxidative phenol-coupling using iron(II) chloride (FeCl 3 ) or iron(II) sulfate (FeSO 4 ) 34,35,36,37,38,39 . 13,14,15,16,17,18,19,20,21,22,23 Recently, with the increasing interest on renewable resources, several bio-based polymers were produced from vanillin or its derivatives.…”

Creating Oxidase–Peroxidase Fusion Enzymes as a Toolbox for Cascade Reactions

“…These results demonstrate that the fusion enzymes are suitable for the production of the taste enhancer divanillin . Apart from being recognized as flavors, vanillin and divanillin are also considered as renewable building blocks for the production of bio‐based plastics . Furthermore, divanillin and related phenolic dimers have an antimetastatic potential .…”

From Lignin‐derived Aromatic Compounds to Novel Biobased Polymers

“…The oxidative coupling of vanillin leading to dialdehyde compounds is also suitable for Schiff base polymerization. Razzaq and co‐workers synthesized 52 by the oxidative dimerization of vanillin following an enzymatic pathway reported by Vosburg and co‐workers in 2010, employing Horseradish Peroxidase . The dialdehyde compound 52 and alkyl diamine (1,2‐diaminoethane, 1,3‐diaminopropane, 1,6‐diaminohexane) were refluxed in ethanol, leading to polymer P45 with a degree of polymerization between 25 and 32 (Scheme ) .…”

“…[ 85 ] The dialdehyde compound 52 and alkyl diamine (1,2-diaminoethane, 1,3-diaminopropane, 1,6-diaminohexane) were refl uxed in ethanol, leading to polymer P45 with a degree of polymerization between 25 and 32 (Scheme 21 ). [ 85 ] The three polymers were stable up to 250 °C. The polymer synthesized with 1,6-diaminohexane complexed with Cu(II), Fe(II), and Co(II).…”