pectins and coniferyl-alcohol

To mimic the lignin polymerization process, mats of bacterial cellulose and of a pectin/cellulose composite were used as a host matrix for in vitro polymerization of coniferyl alcohol. A diffusion cell was used to allow the diffusion of both hydrogen peroxide and coniferyl alcohol into the peroxidase impregnated cellulose mats through dialysis membranes. The results indicate that significant polymerization occurs within the mats. The resulting binary and ternary blends were imaged by scanning electron microscopy (SEM) and characterized by chemical means. The presence of pectin induces a better dispersion of the synthetic lignin in the cellulose network and enhances the proportion of alkyl-aryl-ether in the polymer.

Topics: Cellulose; Diffusion; Gluconacetobacter xylinus; Hydrogen Peroxide; Lignin; Microscopy, Electron, Scanning; Pectins; Peroxidase; Phenols; Polymers

Coniferyl alcohol was polymerised in the presence of pectin and a pectin-DHP complex was isolated. Characterisation of the complex has demonstrated that DHP (20% wt) was covalently linked by ester bonds to the pectin. The water sorption behaviour of the pectin-DHP complex was determined at several relative vapour pressures and compared with those obtained on pectin, DHP and a blend of both polymers in the same proportion as in the complex. The complex exhibited a lower hydrophilicity resulting from three associated phenomena: grafting, pectin-DHP interactions and the formation of a chemical network.

Topics: Chromatography, Gel; Lignin; Pectins; Phenols; Polymers; Water