The application of silane coupling agents to polyolefins such as polyethylene and polypropylene is also under active investigation and Sterman et al. have reported that the combined use of an organic peroxide and a double bond-containing silane such as vinyl silanes and methacrylic silanes is effective on polypropylene in remarkably improving the properties of the FRTP of the polymer.
Hartlein has reported that a good coupling agent for polypropylene is 3-mercaptopropyl Trimethoxysilane and a synergistic effect can be obtained by the combined use of an aminoalkyl silane and a highly chlorinated compound such as chlorinated xylene.
Silane treated feldspar filled polypropylene composites can be prepared using a Polydrive Thermo Haake internal melt mixer. The tensile strength, elongation at break, Young’s modulus, and impact strength can be increased in silane treated composites.
The improvement in tensile strength and elongation at break is due to the enhancement of the interfacial adhesion between feldspar and PP matrix. FTIR spectra analyses can be performed on the untreated feldspar/PP composites and the silane treated feldspar filled PP composites to study the interaction between the polypropylene —(C—H2), feldspar (—OH) group and the amino functional group of silane.