THE ROLE OF TITANIUM-DIOXIDE PIGMENTS IN THE DEGRADATION AND STABILIZATION OF POLYMERS IN THE PLASTICS INDUSTRY

Several factors that titanium dioxide pigments can affect in melt processable thermoplastics are reviewed; UV and thermal stability, discoloration and the evolution of volatiles. The importance of the inorganic coating, present on most grades used in thermoplastics, in reducing the extent of UV and thermal degradation is emphasised. Data are presented on the gloss and chalk loss of uPVC plaques at Florida and loss of tensile properties of PE films on accelerated weathering. These show that the durability ranking of pigments is the same as that which has been well established for paints. © 1990.