Bone and Joint Institute

Title

Sustainable bio-based phenol-formaldehyde resoles using hydrolytically depolymerized kraft lignin

Document Type

Article

Publication Date

11-1-2017

Journal

Molecules

Volume

22

Issue

11

URL with Digital Object Identifier

10.3390/molecules22111850

Abstract

© 2017 by the authors. In this study bio-based bio-phenol-formaldehyde (BPF) resoles were prepared using hydrolytically depolymerized Kraft lignin (DKL) as bio-phenol to partially substitute phenol. The effects of phenol substitution ratio, weight-average molecular weight (Mw) of DKL and formaldehyde-to-phenol (F/P) ratio were also investigated to find the optimum curing temperature for BPF resoles. The results indicated that DKL with Mw ∼1200 g/mol provides a curing temperature of less than 180°C for any substitution level, provided that F/P ratios are controlled. Incorporation of lignin reduced the curing temperature of the resin, however, higher Mw DKL negatively affected the curing process. For any level of lignin Mw, the curing temperature was found to increase with lower F/P ratios at lower phenol substitution levels. At 25% and 50% phenol substitution, increasing the F/P ratio allows for synthesis of resoles with lower curing temperatures. Increasing the phenol substitution from 50% to 75% allows for a broader range of lignin Mw to attain low curing temperatures.

This document is currently not available here.

Share

COinS