Preparation and characterization of cyclo olefin copolymer (COC)/silica nanoparticle composites by solution blending

A series of organic cyclo olefin copolymer (COC)/SiO2 nanocomposites, containing 1, 5, 10 and 15 wt% SiO2 nanoparticles, were prepared by solution blending. The differential scanning calorimetric (DSC) analysis indicated that the glass transition temperature (T (g)) of composites were higher than that of pure COC and raised significantly as the SiO2 content increased from 1 to 15 wt%. The decomposition temperatures (Td) of composites were investigated by thermogravimetric analyzer (TGA) and showed 13 degrees C increase by the addition of 15 wt% SiO2 when compared to pure COC. From the scanning electron microscopic (SEM) observation, finer size of silica was dispersed in the COC matrix without large agglomerates. The light transmittance of COC/SiO2 composites was still higher than 85% as the SiO2 content up to 10 wt%. The oxygen barrier property of the composite film show significant improvement when compared to pure COC.