Inverse gas chromatography for studying interaction of materials used for cellulose fiber/polymer composites

The objective of this research was to use inverse gas chromatography (IGC) to infer fiber-matrix interactions for predicting practical adhesion between cellulose fibers and polystyrene matrix polymer. IGC experiments were performed on polystyrene, untreated, alkyl- and amino-silanated cellulose (lyocell) fibers. The fiber-matrix acid-base interaction was quantified by (1) pairing the acidic parameter (K_A) of one component with the basic parameter (K_B) of another component and (2) observing the adsorption enthalpy of the polymer building blocks (ethylbenzene) onto the fibers. Results show that the cellulose/polystyrene acid-base interaction inferred from interaction parameters is closely correlated to that evaluated from the specific adsorption of ethylbenzene. This feature indicates that the acid-base interactions, which play an important role in the adhesion between fibers and polystyrene, can be conveniently predicted from their respective acid and base parameters (K _A and K_B) prior to composites' manufacture. A specific implication of this study is that treatment with an aminosilane is likely to improve interaction and, hence, bonding with polystyrene in a composite system. Treatment with alkylsilane, on the other hand, would result in a weak interaction with polystyrene. These predictions will be verified in future studies which will correlate materials interactions with interfacial micromechanics in the resulting micro-composites.