Abstract
Arylon, a blend of an aromatic polysulfone and a terpolymer of acrylonitrile–butadiene and α‐methylstyrene, weathers similarly to ABS. However its first‐order rate constant for the loss of unsaturation is only 0.39 cm2(Wh)−1 as against 0.80cm 2(Wh)−1 for ABS. This slower weathering is probably caused by the decrease in light intensity penetrating Arylon compared with ABS as a result of the high degree of light scattering observed in the former.