Chemical Name Butanedioic acid, dimethylester, polymer with 4-hydroxy -2,2,6,6-tetramethyl-1-piperidine ethanol. CAS Number 65447-77-0 Molecular Weight Mn = 3100 - 4000 Applications YS 622 areas of application include polyolefins (PP, PE), olefin copolymers such as EVA as well as blends of polypropylene with elastomers. In addition YS 622 is highly effective in polyacetals, polyamides and polyurethane applications.