The kinetics of light ageing of wood filled composites made from polypropylene filled with unmodified wood flour and with wood flour modified with maleic anhydride (MA) in amounts of 10, 20 and 30% has been investigated.
The investigation shows that the light ageing of wood-filled polypropylene-based composites is an autocatalytic chain process. The decrease of the rate constants with increasing wood content showed that the wood flour had a screening effect on light.
It is established that the modification of wood flour with MA have a stabilising effect on the ageing of the composite materials owing to a decrease in the number of active centres capable of undergoing oxidation, and in the number of the carbonyl groups.
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