| abstract |
1411301 Stabilizing polymers CIBA-GEIGY AG 29 March 1973 [30 March 1972] 15101/73 Headings C3P and C3R [Also in Division C2] Synthetic organic polymers normally subject to UV deterioration are stabilized by the novel piperazine diones of Formula I where R<SP>1</SP> and R<SP>2</SP> are the same or different C 1-12 alkyl group or R<SP>1</SP> and R<SP>2</SP>, together with the common carbon atom, form a monocyclic carbocyclic ring having 5 to 12 ring carbon atoms; n is 1 or 2; when n is 1, R<SP>3</SP> is C 1-20 alkyl and when n is 2, R<SP>3</SP> is a C 2-8 alkylene group; and A is a C 1-6 straight or branched chained alkylene group in which the terminal carbon atoms each bear only hydrogen atoms or one alkyl group. Examples stabilize polyethylene, polypropylene, polystyrene, acrylonitrile - butadienestyrene terpolymer, polyurethane (from toluene diisocyanate and alkylene polyols), polycarbonate (from bisphenol A and phosgene), polyethyleneterephthalate, polymethylmethacrylate, nylon 6,6 and polyphenylene oxide with compounds of Formula I and/or with specific hindered phenol antioxidants. |