Effect of surface treatment in cork reinforced composites

This work explores the possibility of using cork for reinforcing of polypropylene (PP). The cork granules were mixed with PP by extrusion and the mixture was then injected. The hydrophilic character of cork and the hydrophobic character of PP influence negatively the adhesion at the interface between the reinforcement and the matrix. In order to improve it, several chemical modifications of the cork reinforcements were used in this work: treatment with silane, with sodium hydroxide and with a compatibilizing agent MAPP. The interface modifications were studied by scanning electron microscopy (SEM), Goniometry analysis and infrared spectroscopy analysis (IR). The improvement of the mechanical properties was demonstrated by tensile tests. On their basis it was demonstrated that the best interfacial adhesion between cork and PP is achieved by the silane chemical modification (silanization)

Modification of Oil Palm Empty Fruit Bunch Fibers by Nanoparticle Impregnation and Alkali Treatment

Oil palm empty fruit bunch (EFB) fibers were impregnated by copper nanoparticles (CuNPs) through the cationization process as well as treated by alkali solutions. Mechanical properties of different single fibers were measured and analysed by the Weibull statistical distribution. The weak link scaling of Weibull analysis has provided valuable information to scale the strength of one EFB fiber to predict the strength of other one. The impregnation and interfacial interaction of CuNPs with fibers has been analysed by Fourier transformed infrared spectroscopy, X-ray diffraction study, field emission scanning electron microscopy, energy dispersive X-ray study and thermogravimetric analysis. A significant increase in mechanical property of modified fibers with respect to the control ones has been observed. The crystallinity and thermal stability of the treated fibers were also found to be changed. These findings strongly suggest that CuNPs can be used as an effective reinforcing agent in natural fibers to improve their mechanical property and durability