Composites of rubberwood flour (RWF) and recycled polypropylene
(rPP) were produced into panel samples by using a twin-screw extruder. The effects
of mixture ratios, including rPP, RWF, maleic anhydride-grafted polypropylene (MAPP),
and ultraviolet (UV) stabilizer, on creep behavior were studied in a D-optimal mixture
design. Creep was significantly affected by the composition. Increasing the fraction of
RWF decreased creep, but the increasing additions of MAPP and UV stabilizer
increased creep.