Ciba-geigy Corporation

Ciba Specialty Chemicals Corporation

Bernard Gilg

Rita Pitteloud

Gerhard Rytz

Helmut Muller

Jean Rody

Werner Stauffer

Margot Clauss

Kurt Stinsky

Samuel Evans

Mario Slongo

Paul Dubs

Rolf Mulhaupt

Siegfried Rosenberger

Heimo Brunetti

Kurt Schwarzenbach

The invention relates to a composition comprising a) a styrene, &agr;-methylstyrene or p-methylstyrene homo- or copolymer; b) a bromine-containing flame retardant; c) a UV absorber; d) a sterically hindered amine and e) an epoxidized fatty acid. This invention also relates to the use of the light stabilizer mixture consisting of the components c), d) and e) for light-stabilizing a styrene, &agr;-methylstyrene or p-methylstyrene homo- or copolymer finished with a bromine-containing flame retardant as well as to a process for the light-stabilization thereof. Adding an epoxidized fatty acid to a UV absorber and a sterically hindered amine in styrene, &agr;-methylstyrene or p-methylstyrene homo- or copolymer finished with bromine-containing flame retardants results in an unexpected synergistic effect in the light stability. In particular, it is possible to markedly reduce the discoloration of the finished polymer which takes place in the course of irradiation.

Light-stabilized flameproof styrene homopolymers and copolymers

Organic materials having excellent stability against oxidative, thermal or light-induced degradation comprise as stabilisers (i) at least one compound of formula I ##STR1## wherein the general symbols are as defined in claim 1, and (ii) calcium lactate and/or calcium stearoyl-2-lactylate.

Stabilizer mixture for organic materials

The present invention relates to synergistic mixtures of at least one 2,4-dimethyl-6-s-alkyl phenol and at least one selected sterically hindered phenol according to formula II ##STR1## The variable 'n' is 1, 2 or 4. X.sub.1 is tert-butyl. X.sub.2 is C.sub.1 -C.sub.4 alkyl. X.sub.3, when n is 1, is C.sub.1 -C.sub.20 alkyl, a triazinylamino group, or a --A.sub.1 --COO--A.sub.2 or --A.sub.1 --CONH--A.sub.2 group. X.sub.3, when n is 2, is a --E.sub.1 --COO--E.sub.2 --OOC--E.sub.3 -- or --E.sub.1 --CONH--E.sub.2 --NHCO--E.sub.3 -- group. X.sub.3, when n is 4, is �--G.sub.1 --COO!.sub.4 --G.sub.2. The instant synergistic mixtures can be used to stabilize selected organic polymers against thermal, oxidative and/or actinic degradation.

Synergistic mixture consisting of a 2,4-dimethyl-6-S-alkylphenol and a

The novel compounds of the formula I ##STR1## in which A is a group of the formula IIa or IIb, ##STR2## Y is oxygen, methylene, ethylidene or a &gt;C.dbd.C(CH.sub.3).sub.2 group, Z is nitrogen, ##STR3## R.sub.1 and R.sub.2 are, for example C.sub.1 -C.sub.5 alkyl, R.sub.3 and R.sub.4 are, for example, hydrogen or methyl, and R.sub.5, R.sub.6, R.sub.7, R.sub.8, R.sub.9, R.sub.10, R.sub.11, R.sub.12, R.sub.13 and R.sub.14 are, for example, hydrogen, are suitable for stabilizing organic material against oxidative, thermal or light-induced degradation.

Bisphenol ester derivatives

Stabilisers of formula I ##STR1## wherein R.sub.1 and R.sub.2 may be C.sub.1 -C.sub.5 alkyl, the substituents R.sub.3 to R.sub.8 may be hydrogen, the variable n may be 1 or 2, and, when n is 1, A may be an alkoxy radical, and, when n is 2, A may be a diamine radical.

Compositions comprising an organic material which is sensitive to thermal, oxidative and/or actinic degradation and at least one compound of the formula I ##STR1## in which Z.sub.1 and Z.sub.2 independently of one another are C.sub.1 -C.sub.18 alkyl, C.sub.5 -C.sub.8 cycloalkyl, phenyl, phenyl-C.sub.1 -C.sub.4 alkyl or (C.sub.1 -C.sub.4 alkyl)phenyl and

Alkanediphenols

A process for producing an emulsion graft copolymer, which comprises grafting a vinyl aromatic monomer and a comonomer onto a rubber latex in the presence of an iron (II) redox system as polymerization catalyst and coagulating the graft copolymer latex with an alkaline earth metal compound, characterized in that the pH of the coagulated slurry is adjusted to a value ranging from 8 to 12

Process for producing an emulsion graft copolymer

ABS copolymers and similar styrene or .alpha.-methylstyrene copolymers which contain an elastomer phase are stabilized against light-induced degradation by a) incorporation of a copolymerizable sterically hindered amine in, and b) addition of a non-copolymerizable sterically hindered amine to, the copolymer. Preferred sterically hindered amines are polyalkylpiperidines.

Process for the preparation of stabilized styrene copolymers containing

ABS copolymers and similar styrene or .alpha.-methylstyrene copolymers with contain an elastomer phase are stabilized against light-induced degradation by a) incorporation of a copolymerizable sterically hindered amine in, and b) addition of a non-copolymerizable sterically hindered amine to, the copolymer. Preferred sterically hindered amines are polyalkylpiperidines.

Stabilized styrene copolymers containing elastomer particles modified

Copolymers of styrene or a-methylstyrene and at least one comonomer, containing crosslinked elastomer particles, can be light-stabilized by modifying the elastomer particles by copolymerization with a suitable derivative of a sterically hindered amine. The modification is preferably carried out by graft polymerization, the elastomer used preferably being polybutadiene.

Stabilized styrene copolymers containing elastomer particles

Compounds of the formula V ##STR1## wherein R.sup.2 is straight-chain or branched alkyl of 1 to 8 carbon atoms, cycloalkyl, aryl, alkaryl or aralkyl, L is a bivalent radical, for example --SCH.sub.2 CO.O(CH.sub.2 CH.sub.2 S).sub.y --CH.sub.2 CH.sub.2 -- or --O.COC.sub.p H.sub.2p -- wherein y is a number from 1 to 3 and p is a number from 1 to 18.

Mercaptophenol stabilizers

Stabilizer system consisting of (a) at least one sterically hindered cyclic amine of the formula I ##STR1## in which q is 1 or 2, X represents an organic grouping which complements the nitrogen-containing ring to give a 5-membered, 6-membered or 7-membered ring, R.sub.1 and R.sub.2 represent methyl or together represent --(CH.sub.2).sub.5 --, R.sub.3 represents methyl, R.sub.4 represents alkyl with 1-5 carbon atoms or together with R.sub.3 represents the radicals --(CH.sub.2).sub.4 --, --(CH.sub.2).sub.5 -- ##STR2## and, if q is 1, Y denotes hydrogen, --0.sup.., hydroxyl, alkyl, substituted akyl, alkenyl, alkinyl, aralkyl, substituted aralkyl or acyl or, if q is 2, Y denotes alkylene, alkenylene, alkinylene, cycloalkylene or aralkylene, and (b) at least one co-stabilizer for stabilizing plastics.

Stabilizer system for stabilizing styrene polymers

Stabilizer system consisting of (a) at least one sterically hindered cyclic amine of the formula I ##STR1## in which q is 1 or 2, X represents an organic grouping which complements the nitrogen-containing ring to give a 5-membered, 6-membered or 7-membered ring, R.sub.1 and R.sub.2 represent methyl or together represent --(CH.sub.2).sub.5 --, R.sub.3 represents methyl, R.sub.4 represents alkyl with 1-5 carbon atoms or together with R.sub.3 represents the radicals --(CH.sub.2).sub.4 --, --(CH.sub.2).sub.5 -- ##STR2## and, if q is 1, Y denotes hydrogen, --O.multidot., hydroxyl alkyl, substituted alkyl, alkenyl, alkinyl, aralkyl, substituted aralkyl or acyl or, if q is 2, Y denotes alkylene, alkenylene, alkinylene, cycloalkylene or aralkylene, and (b) at least one co-stabilizer for stabilizing plastics.

Stabilizer system and its use for stabilizing styrene polymers

Bicyclic phosphites are used alone or in combination with other stabilisers for stabilising polyolefines.

Growing community of inventors

St. Louis-la-Chaussee, France

Bernard Gilg