Stabiliser CdS is Cadmium Stearate which provides excellent thermal stability when used in combination with other stabilisers or metal carboxylates. It is normally used in combination with Barium Stearate which gives synergistic effect. Different ratios of Barium and Cadmium Stearates are used for a variety of applications.

Stabiliser CdS is effective in giving protection against UV light and sunlight and can be used in making transparent PVC compounds. It is not used alone as the thermal break-down is abrupt. It's stabilising action produces it's chloride which further increases degradation of the polymer drastically. Hence it is never used alone but in conjunction with other stearates like Barium stearate which neutralises the effect of Cadmium Chloride. In combination with stabilizer BS, in equal amounts, it gives increased heat stability and good UV light protection. Use of epoxy and a phosphite chelator will further improve the stability. Thus in combination, it gives both, short and long term stability and colour retention.