Multifunctional Nanoparticles at the Hydrophilic and Hydrophobic Interface

The objective of this study was to investigate a technique to obtain inorganic nanoparticle impregnated wood fiber reinforcement in the thermoplastic matrix. Inorganic nanoparticulates as a function of void filler and interfacial compatibilizer were generated through the chemically reconstruction method using two different ionic salts (CaCh to Na2C03). The longer reaction time of two ionic salts provided decreased nanoparticle sizes and uniform distribution. The increased molar ratios of CaCh to Na2C03 provided higher precipitation levels of CaC03. However, longer reaction times and higher ionic salt ratios resulted in a larger CaC03 crystal structure (>1 urn in diameter) which is not desirable because of 100 to 200 urn micropore sizes. SEM-EDX results also indicated Ca++ ion values observed in the cell wall of the fiber cross section. Reaction temperatures from 120 to 160°C and a concentration of 30% were the effective conditions, which provided a highest Ca++ ion value in the cell wall. The inorganic nanoparticle size and loading were controlled by different parameters of reaction time, temperature, molar ratio and moisture content. It should be noticed that the solid CaC03 crystal structure was relatively larger than chemically reconstruction nanoparticles on fiber surface. Furthermore, the reconstructed inorganic nanoparticles were more effective to be impregnated into the inner cellular structure.