Sonochemical Analysis of Solvent Mixtures Used for Surface Treatment of Natural Fibers

Surface treatment of natural fibers with the help of compatible solvent mixture is an important step in preparation of different reinforcement materials in the fiber engineering and technology. The ultrasonic waves can be used to study the compatibility between the solvent mixtures and the lignin present in the surface of the natural fibers, which may enable fibers to be fillers for making of composites. The ultrasonic velocity was determined in binary mixtures of ethanol-acetone and methanol-acetone with different frequencies (1 MHz, 3 MHz and 5 MHz) at temperature 303 K. The different acoustic parameters like acoustic impedance, bulk modulus, intermolecular free length and compressibility are computed from the ultrasonic velocity and experimentally determined densities. The variations of these parameters are discussed in terms of different intermolecular interactions present in the solvent mixture. The compatibility of solvent mixtures was determined from the comparative values of thermo dynamical acoustic parameters. The interaction of selected solvent mixture with surface of the fiber was investigated. The sonochemical miscibility of the mixtures may be suitable solvent for bleaching of surface of fibers.