Abstract: Polyolefins are thermomechanically degraded in a twin-screw extruder without a downstream degradation apparatus, at from 300.degree. to 550.degree. C. and from 1 to 100 bar and in average residence times of the reaction mixture of from 0.5 to 10 minutes, by a process in which the pressure in the twin-screw extruder is changed periodically or aperiodically with a fluctuation of from 0.5 to 30 bar. The novel process is particularly suitable for the degradation of polypropylene.

Abstract: Polymers that can be obtained by suspension polymerization of 50 to 100% by weight of at least one compound selected from the group comprising C.sub.1 -C.sub.18 -alkyl esters of acrylic acid and methacrylic acid, and 0 to 50% by weight of further, free radical-polymerizable monomers in the presence of a buffer selected from the group comprising citric acid, alkali metal citrates, alkaline earth metal citrates and ammonium citrates, and also a process for preparing these polymers and their use in the production of molded articles.

Abstract: An expandable styrene polymer comprisinga) from 0 to 90% by weight of a styrene polymer or styrene copolymer other than b) contains at least 50% by weight of copolymerized styrene,b) from 10 to 100% by weight of a styrene/methacrylamide copolymer comprising from 0.5 to 50% by weight of at least one copolymerized N-substituted methacrylamide of the formula I ##STR1## where R.sup.1 and R.sup.2 are identical or different and are hydrogen, C.sub.1 - to C.sub.15 -alkyl, C.sub.6 - to C.sub.16 -cycloalkyl or C.sub.6 - to C.sub.20 -aryl, it being possible, if R.sup.1 and R.sup.2 contain at least 2 carbon atoms, for at least 2 carbon atoms to be linked via hetero atoms, andc) from 1 to 15% by weight, based on the sum of a) and b), of an aliphatic C.sub.3 - to C.sub.9 -hydrocarbon and/or carbon dioxide as blowing agent.

Abstract: Carboxyl-containing isobutene copolymers are obtainablea) by cationic polymerization of a mixture of from 1 to 99 mol % of isobutene and from 99 to 1 mol % of a 2-methylalk-1-ene at less than 20.degree. C. in the presence of a halogen-containing Lewis acid andb) subsequent grafting of the isobutene copolymer obtainable in this manner with an .alpha.,.beta.-ethylenically unsaturated carboxylic acid or carboxylic acid derivative at above 100.degree. C. and in the presence of a free radical initiator.Such carboxyl-containing isobutene copolymers are particularly suitable as adhesive raw materials or as sealing compounds.

Abstract: The invention relates to expandable styrene polymers for elastic polystyrene foams, comprisinga) from 50 to 90% by weight of polystyrene and/or a styrene copolymer containing at least 50% by weight of copolymerized styrene,b) from 5 to 30% by weight of at least one styrene-soluble elastomer,c) from 5 to 20% by weight of at least one block copolymer containing styrene as one component,d) from 1 to 15% by weight, based on the sum of a), b) and c), of a low-boiling blowing agent, and, if desired,e) conventional additives in effective amounts,where, in the unfoamed polystyrene beads, component b) is in the form of cell particles and component c) is in the form of particles having a mean size of from 0.2 to 2 .mu.m in the polystyrene phase, and to foams and foam moldings produced therefrom.

Abstract: Molding materials having stress cracking resistance containingA) from 49 to 99% by weight of a polymer obtainable by polymerizing a C.sub.1 -C.sub.20 -alkyl ester of methacrylic or acrylic acid or a mixture of said esters,B) from 0.95 to 50% by weight of a polymer obtainable by polymerizing a monomer mixture comprisingb.sub.1) from 75 to 82% by weight of a vinyl aromatic monomer andb.sub.2) from 18 to 25% by weight of acrylonitrile or methacrylonitrile or a mixture thereof, andC) from 0.05 to 1% by weight of a mixture containingc.sub.1) a triaryl phosphite of the formula I ##STR1## c.sub.2) an amine of the formula II ##STR2## where n is from 2 to 10, c.sub.3) a benzotriazole of the formula III ##STR3## and C.sub.4) a phenol.

Abstract: A polymer useful for preparing moldings and comprising essentially units of the formula I ##STR1## where R.sup.1 and R.sup.2 are each hydrogen or methyl, andR.sup.3 is hydrogen, C.sub.1 -C.sub.18 -alkyl, C.sub.5 -C.sub.8 -cycloalkyl, C.sub.6 -C.sub.10 -aryl or C.sub.6 -C.sub.10 -aryl-C.sub.1 -C.sub.4 -alkyl, each of which may be monosubstituted, disubstituted or trisubstituted by radicals selected from the group consisting of C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy and halogen, is obtainable by reacting a polymer based on C.sub.1 -C.sub.20 -alkyl esters of (meth)acrylic acid with a primary amine of the general formula IIR.sup.3 NH.sub.2 IIin the presence of a compound selected from the group consisting of phosphinic acid and phosphonic acid and their alkali metal, alkaline earth metal, aluminum and ammonium salts, wherein the ammonium ion can be monosubstituted, disubstituted, trisubstituted or tetrasubstituted by C.sub.1 -C.sub.4 -alkyl and/or C.sub.5 -C.sub.8 -cycloalkyl, or mixtures thereof.

Abstract: A thermoplastic molding material containing, based on the sum of its constituents A, B and C,A: 70 to 99% by weight of a thermoplastic resin A comprising, based on A,A1: 50 to 100% by weight of a hard matrix A1 comprising, based on A1,A11: 50 to 95% by weight of units of an aromatic vinyl compound or methyl methacrylate or their mixtures (A11) andA12: 5 to 50% by weight of units of acrylonitrile A12;A2: up to 50% by weight of a rubber-elastic particulate graft copolymer A2 comprising, based on A2,A21: 30 to 80% by weight of at least one elastomeric graft base A21 having a median particle size of from 30 to 1000 nm comprising, based on A21,A211: 50 to 100% by weight of units of a 1,3-diene or a C.sub.4 -C.sub.

Abstract: Carboxyl-containing isobutene copolymers are obtainablea) by cationic polymerization of a mixture of from 1 to 99 mol % of isobutene and from 99 to 1 mol % of a 2-methylalk-1-ene at less than 20.degree. C. in the presence of a halogen-containing Lewis acid andb) subsequent grafting of the isobutene copolymer obtainable in this manner with an .alpha.,.beta.-ethylenically unsaturated carboxylic acid or carboxylic acid derivative at above 100.degree. C. and in the presence of a free radical initiator.Such carboxyl-containing isobutene copolymers are particularly suitable as adhesive raw materials or as sealing compounds.

Abstract: Carboxyl-containing copolymers of ethylene are prepared by polymer-analogous pyrolytic ester cleavage of copolymers consisting ofa) from 60 to 99.9 mol% of ethylene,b) from 0.1 to 40 mol% of C.sub.4 -C.sub.8 -tert-alkyl esters of copolymerizable C.sub.3 -C.sub.12 -carboxylic acids andc) from 0 to 20 mol% of further copolymerizable monomers by a method in which pyrolytic ester cleavage is carried out at from 150.degree. to 250.degree. C. in the presence of organic sulfonic acids, in the absence of a solvent and in the virtual absence of free radical initiators.

Abstract: An expandable styrene polymer comprisinga) from 0 to 90% by weight of a styrene polymer or styrene copolymer other than b) contains at least 50% by weight of copolymerized styrene,b) from 10 to 100% by weight of a styrene/methacrylamide copolymer comprising from 0.5 to 50% by weight of at least one copolymerized N-substituted methacrylamide of the formula I ##STR1## where R.sup.1 and R.sup.2 are identical or different and are hydrogen, C.sub.1 - to C.sub.15 -alkyl, C.sub.6 - to C.sub.16 -cycloalkyl or C.sub.6 - to C.sub.20 -aryl, it being possible, if R.sup.1 and R.sup.2 contain at least 2 carbon atoms, for at least 2 carbon atoms to be linked via hetero atoms, andc) from 1 to 15% by weight, based on the sum of a) and b), of an aliphatic C.sub.3 - to C.sub.9 -hydrocarbon and/or carbon dioxide as blowing agent.

Abstract: Molding materials contain from 5 to 50% by weight of a first polymer obtained by polymerizing a C.sub.1 -C.sub.20 -alkyl ester of methacrylic or acrylic acid;from 5 to 50% by weight of a second polymer obtained by polymerizing a monomer mixture offrom 75 to 82% by weight of a vinyl aromatic monomer and from 18 to 25% by weight of acrylonitrile or methacrylonitrile;from 10 to 40% by weight of a third polymer containing from 10 to 90% by weight of units of the general formula I ##STR1## where R.sup.1 is hydrogen or C.sub.1 -C.sub.4 -alkyl and R.sup.2 is C.sub.1 -C.sub.18 -alkyl, C.sub.5 -C.sub.12 -cycloalkyl, C.sub.6 -C.sub.10 -aryl or C.sub.6 -C.sub.10 -aryl-C.sub.1 -C.sub.4 -alkyl, andfrom 10 to 90% by weight of a C.sub.1 -C.sub.20 -alkyl ester of methacrylic or acrylic acid;from 5 to 60% by weight of a graft copolymer having a mean particle diameter (weight average) of less than 200 nm and obtained by polymerizing from 20 to 70% by weight of a monomer mixture offrom 30 to 100% by weight of a C.sub.1 -C.sub.

Abstract: Reduction of the wall coating in reaction containers in the suspension polymerization of monomers containing acrylate and/or methacrylate groups and use of a buffer and of a dispersant for reducing the wall coating in reaction containers in the suspension polymerization of monomers containing acrylate and/or methacrylate groups.

Abstract: At least 99% pure 2,2'[oxybis (methylene)]bis-2-propenoic acidCH.sub.2 .dbd.C(COOH)CH.sub.2 --O--CH.sub.2 C(COOH).dbd.CH.sub.2is prepared by hydrolyzing an ester thereof in an aqueous basic medium and then acidifying the resultant salt.

Abstract: A polymer useful for preparing shaped articles comprises essentially repeat units of the formula I ##STR1## where R.sup.1 and R.sup.2 are each hydrogen or methyl, andR.sup.3 is C.sub.6 -C.sub.14 -aryl, which may be monosubstituted, disubstituted or trisubstituted by radicals selected from the group consisting of C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy and halogen,and is obtainable by reacting a polymer based on C.sub.1 -C.sub.20 -alkyl esters of methacrylic acid or of acrylic acid or mixtures of such esters with an aromatic amine of the general formula IIR.sup.3 NH.sub.2 IIin the presence of an amine having a pK.sub.b value .ltoreq.9.

Abstract: A process for isolating and purifying oxadimethacrylics of the general formula ICH.sub.2 .dbd.C(A)CH.sub.2 --O--CH.sub.2 C(B).dbd.CH.sub.2 Iwhere A and B are selected from the group consisting of --COOR.sup.1, --COR.sup.1, --CONR.sup.2 R.sup.3 and --CN and R.sup.1, R.sup.2 and R.sup.3 are each defined as follows:R.sup.1 is hydrogen, alkyl, substituted or unsubstituted cycloalkyl or cycloalkylalkyl, hydroxyalkyl, aminoalkyl, N-alkylaminoalkyl, N,N-dialkylaminoalkyl, substituted or unsubstituted aryl or arylalkyl,R.sup.2 and R.sup.3 are each hydrogen, alkyl, substituted or substituted cycloalkyl or cycloalkylalkyl, substituted or unsubstituted aryl or arylalkyl,comprises precipitating or crystallizing them from their solutions that contain at least one liquid hydrocarbon compound.

Abstract: Molding materials based on polymethyl methacrylate comprising essentiallyA) from 99.99 to 95.0% by weight of a mixture comprising essentiallya.sub.1) from 5 to 95% by weight of polymethyl methacrylate, obtainable by polymerizing a mixture comprising essentiallya.sub.11) from 80 to 100% by weight of methyl methacrylate anda.sub.12) from 0 to 20% by weight of a C.sub.1 -C.sub.20 -alkyl ester of acrylic acid, anda.sub.2) from 95 to 5% by weight of a multistage graft copolymer based on a C.sub.1 -C.sub.20 -alkyl ester of acrylic and/or methacrylic acid andB) from 0.01 to 5.0% by weight of a polysiloxane of the general formula I ##STR1## where R.sup.1 is C.sub.1 -C.sub.6 -alkyl or C.sub.6 -C.sub.10 -aryl,R.sup.2 is hydroxy-C.sub.1 -C.sub.6 -alkyl or amino-C.sub.1 -C.sub.6 -alkyl, andn is a natural number from 5 to 200.

Abstract: A polymer useful for preparing shaped articles comprises essentially repeat units of the formula I ##STR1## where R.sup.1 and R.sup.2 are each hydrogen or methyl, andR.sup.3 is C.sub.6 -C.sub.14 -aryl, which may be monosubstituted, disubstituted or trisubstituted by radicals selected from the group consisting of C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy and halogen,and is obtainable by reacting a polymer based on C.sub.1 -C.sub.20 -alkyl esters of metharcylic acid or of arcylic acid or mixtures of such esters with an aromatic amine of the general formula IIR.sup.3 NH.sub.2 IIin the presence of an amine having a pK.sub.b value .ltoreq.9.

Abstract: A polymer comprising essentially units of formula I ##STR1## where R.sup.1 and R.sup.2 are each hydrogen or methyl, andR.sup.3 is C.sub.4 -C.sub.18 -alkyl, C.sub.5 -C.sub.8 -cycloalkyl, C.sub.6 -C.sub.10 -aryl or C.sub.6 -C.sub.10 -aryl-C.sub.1 -C.sub.4 -alkyl, each of which except for the C.sub.4 -C.sub.18 -alkyl may be monosubstituted, disubstituted or trisubstituted by radicals selected from the group consisting of C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy and halogen, and having a carboxyl and anhydride group content of equal to or less than 0.40 equivalent per kilogram of polymer and an inherent color (measured as yellowness index) of equal to or less than 2.0, is obtainable by reacting a polymer based on C.sub.1 -C.sub.20 -alkyl esters of (meth)acrylic acid with a primary amine of the general formula IIR.sup.3 NH.sub.2 IIby removing the alcohol that forms during the reaction from the reaction mixture.

Abstract: Copolymers obtainable by(I) copolymerizing a monomer mixture comprising(A) 1 to 98% by weight of a monomer of the formula I ##STR1## where: R.sup.1 to R.sup.6 are hydrogen, C.sub.1 -C.sub.10 -alkyl, C.sub.1 -C.sub.10 -alkoxy, it being possible in the alkyl or alkoxy radicals having more than one carbon atom for an oxygen atom to be inserted in each case between two carbon atoms, C.sub.5 -C.sub.8 -cycloalkyl, unsubstituted or substituted C.sub.6 -C.sub.10 -aryl, C.sub.6-C.sub.10 -aryl-C.sub.1 -C.sub.10 -alkyl, C.sub.6 -C.sub.10 -aryloxy, cyano, halogen, --CO--O--R.sup.7, --O--CO--R.sup.7 or --CO--NR.sup.7 R.sup.8, whereR.sup.7 and R.sup.8 are hydrogen, C.sub.1 -C.sub.10 -alkyl, C.sub.5 -C.sub.8 -cycloalkyl, unsubstituted or substituted C.sub.6 -C.sub.10 -aryl or C.sub.6 -C.sub.10 -aryl-C.sub.1 -C.sub.10 -alkyl;p is 0, 1 or 2;Z is --CH.sub.2 --, oxygen or sulfur;Y is oxygen or --N--R.sup.9, whereR.sup.9 is hydrogen, C.sub.1 -C.sub.22 -alkyl, C.sub.5 -C.sub.12 -cycloalkyl, unsubstituted or substituted C.sub.