Phenol formaldehyde resin modified by cellulose and lignin nanomaterials: Review and recent progress.

In recent years, growing consideration of the concepts of ecological sustainability, environmentally friendly, recyclability, non-toxicity and biodegradability towards a green environment, have led scientists to focus on the utilization of natural fibers as green reinforcing agents for improving thermal, physical, and mechanical characteristics of composites. In this way, cellulose and lignin (nano) materials are receiving global attention due to their unique and potentially useful features, containing abundance, renewability, low cost, excellent physical-mechanical properties, environmental friendliness, and low weight. Therefore, this research, addressed a survey of the literature on extending the performance of phenol-formaldehyde (phenolic) composites reinforced by cellulose and lignin nano materials that were explored in the last decade. Physical, mechanical behavior and thermal stability of the phenolic composites were comprehensively examined. Indeed, different types of phenolic composites modified with nanocellulose and nanolignin have been made using various advanced synthesis processes. The results were unanimous and highlighted the remarkable effect of nanocellulose and nanolignin on improving the overall performance of the fabricated composites.