Nano-titanium Dioxide Modified High-density Polyethylene Anti-aging Research

Polymer composites filled with inorganic or organic fillers could be widelyused in industries including electronics, packaging, medical and health cares, tools, andautomobile, etc. due to their excellent chemical and physical properties compared to thoseof pure polymeric materials. Inorganic polymer composites have advantages of thepolymeric properties together with characteristics of inorganic particles. The homogeneousdispersion of the filler particles in the polymeric matrix may improve the materialcharacteristics.TiO2has been widely used because of its＇various merits, such as optical and electronicproperties, low costs, high photocatalytic activity, chemical stability and non-toxicity,anti-bacterial agent, UV protection and environmental purification. TiO2nanoparticleswere surface modified by KH570first and then combined with HDPE fabricatingnanocomposites by melt blending process. By thermogravimetric (TG), infrared spectra(FTIR), transmission electron microscopy (TEM), particle size analyzer tested andanalyzed the bare and modified TiO2nanoparticles. By X-ray diffraction (XRD), scanningelectron microscope (SEM), differential scanning calorimetry (DSC) and tensile impacttested and analyzed the before and after aging HDPE/TiO2nanocomposites. Resultsshowed that:TiO2nanoparticles in anhydrous ethanol medium under80℃water bath heatingtreatment for8h could obtain a good surface grafting coupling agent. Surface grafting ofTiO2nanoparticles were observed with good dispersion through TEM, and reached theexpected effects.Observed by SEM, modified TiO2nanoparticles in HDPE matrix showed gooddispersion and less aggregate. By TG test HDPE/TiO2nanocomposites had higher thermaldecomposition temperature than pure HDPE. Comparing pure HDPE and nanoparticlemodified HDPE composites on their mechanical properties, the paper found that the tensileproperties of HDPE/TiO2nanocomposites were improved obviously.Materials through accelerated aging after27days were tesed by DSC, TG and tensileimpact test, and results showed that thermodynamic properties significantly decreased, butcompared with pure HDPE materials, the thermodynamic and mechanical properties ofHDPE/TiO2nanocomposites were decreased less. The conclusion that adding rutile typenano-TiO2could improve the aging resistance of HDPE was drawn out.