Inverse gas chromatography as a tool to characterize ligno-cellulosic fibers modified for composite applications

Inverse gas chromatography (IGC) was used to characterize ligno-cellulosic fiber modified for composite applications. The surface properties of the paper fiber was modified by solution grafting of maleic anhydride functionalized polypropylene (PPgMA): We have investigated the influence of the maleic anhydride content and the chain length of the PPgMA on the surface modifications involved in the solution grafting process. Using IGC at infinite dilution, the evolution of the dispersive component of surface energy with such treatments and the variation of the paper fiber acid/base behavior was determined. The treatment by PPgMA was found to reduce the acidic character of the paper fiber and to enhance its basic character. Moreover, increasing the chain length of the PPgMA resulted in a reduction of both the hydrophilic character of the fiber and its acidic character, while increasing the anhydride content of the PPgMA enhanced the basic character of the fiber. Finally, using IGC at finite concentration, it is observed that reducing the chain length of PPgMA contributes to reducing the specific area of the paper fiber.