INFLUENCE OF CARBONISED RICE HUSK FILLER ON CHANGES IN DEFORMATION AND STRENGTH PROPERTIES OF POLYETHYLENE DURING THERMAL AGEING

The influence of a new filler of natural origin on the thermal oxidation process of high-pressure polyethylene has been studied. The studied filler is carbonized rice husk, a waste product of agricultural production. It has been established that CSF exhibits some thermostabilising effect, preventing the decrease of deformation and strength characteristics of the polymer after its exposure for 3 hours at 170ºC. The introduction of CSF allows to keep the yield strength at the level of 77% (10% wt. CSF) and 46% (5% wt. CSF), while for unfilled aged LDPE this index does not exceed 3% of the initial sample. The breaking stress of the filled samples remains at the level of the unoxidized ones. A synergetic effect was revealed when the investigated filler and standard antioxidant Irganox 1010 were used. At the introduction of 10% wt. of CSF and 0,2% wt. of phenolic stabilizer, there is no decrease in destructive stress after the thermal aging of the material.