Thermal degradation of paper sheets made from wood treated with phenolic resin and bagasse pulps

Abstract

Phenol-formaldehyde resin of resol and novolac types were precipitated in a predetermined concentration onto wood and bagasse fibres. In addition, use has been made of the residual lignin in bagasse to prepare phenol-lignin-formaldehyde (PLF) inside the fibres. Thermal degradation of paper sheets made from resin-treated as well as untreated wood, and bagasse pulps was carried out by differential thermal analysis (DTA) and thermogravimetric analysis (TGA). A method was developed to evaluate the most reasonable order of reaction for the two thermal degradation processes observed in the TGA profiles. It has been deduced that neither addition of resin nor in situ formation of PLF affect the order of any of the degradation processes. These were approximately first-order in the first process, and third-order in the second. An increase in the total activation energy was observed on addition of the resin or in situ formation inside the fibres.