Cellulose Reinforcement of Phenol Formaldehyde: Characterization and Chemometric Elucidation

Abstract

Micro sized crystalline cellulose was uniformly dispersed at loadings of 0, 3, 6, and 10% (by weight) in phenol formaldehyde (PF) and tested for thermal properties and shear strength. The application of cellulose into the PF matrix is considered beneficial because an increase in composite strength will allow for the reduction of petroleum based PF utilized while simultaneously lowering overall formaldehyde concentrations. Characterization studies found this system to exhibit cure temperatures in a very narrow temperature range regardless of cellulose loading which would assist in process changes during manufacturing; however, viscosity increases with cellulose loading was significant and could be a limiting factor. The heat of reaction and nonlinear behavior in lap shear strength with cellulose loading suggests an interaction between cellulose and PF polymer which appeared optimized at 3% cellulose. Finally, utilizing novel chemometric techniques, we were able to partition out the variation in FTIR spectra attributable to a) bulk PF cure and b) cellulose to PF interaction.