Characterization of purified CO2 precipitated Kraft lignin (PCO2KL) for the production of adhesives

摘要

Industrial purified CO2-precipitated Kraft lignin (PCO2KL) from softwood was characterized with the intent of incorporating it into phenolic adhesive resins. This lignin was chemically characterized by means of elemental analysis, functional groups analysis, molecular weight distribution, Mannich reactivity and thermal stability analysis. Results from the study showed that this lignin has a high level of purity with total lignin content around 91% and low carbohydrate and ash content. The PCO2KL showed a large amount of a high molecular weight fraction. It can be concluded that this lignin may be a good raw material for lignin derivatives such as lignin-containing phenol-formaldehyde resins.