Abstract: The invention relates to a process for the preparation of a thermoplastic elastomer comprising preparing a blend of a rubber and a thermoplastic resin, in which the rubber is at least partially vulcanized by using a phenolic curative. The invention is that, to overcome problems with surface quality, an effective amount of a Lewis base is added after the desired degree of vulcanization of the rubber is obtained.The invention also relates to a process for the preparation of an UV-stable thermoplastic elastomer.

Abstract: Impact resistant polyamide composition containing more than 45 wt. % polyamide and relatively minor amounts of an impact modifier. The impact modifier is an elastomer with groups that are reactive with respect to the polyamide. The impact modifier has an adverse effect on the high-temperature properties, which were already poor. According to the invention, compositions of polyamide, impact modifier and a copolymer of a vinylaromatic compound, in particular styrene, and maleic anhydride have improved high-temperature properties while maintaining good impact resistance.

Abstract: The invention relates to a graft copolymer obtainable by reacting a rubbery base polymer, which has been provided with hydroperoxide groups via photo-oxidation, with one or more radical-polymerizable graft monomers, the graft copolymer being based upon 90-20 parts of a rubbery base polymer containing at least 4 (four) hydroperoxide groups per rubber chain and 80-10 parts of one or more of the graft monomers.

Abstract: New polymer composition which has excellent thermal stability, good impact resistance and processability, containing the following compounds:a) 20-75 wt. % of a graft copolymer which contains 10-90 wt. % rubber and grafted on the rubber a copolymer of acrylonitrile and styrene or .alpha.-methylstyreneb) 6-50 wt. % of a copolymer of styrene or .alpha.-methylstyrene containing 20-32 wt. % maleic anhydride, with a molecular weight of 50,000-500,000c) 5-70 wt. % polyamide andd) 0-30 wt. % of a copolymer of styrene or .alpha.-methylstyrene and acrylonitrile.

Abstract: A thermoplastic moulding compound based on a rubber-modified copolymer consisting of styrene and/or .alpha.-methylstyrene and maleic anhydride, wherein the moulding compound is composed of a mixture of:A. 50-95% (wt) of a copolymer consisting of:(i) 50-95% (wt) styrene and/or .alpha.-methylstyrene,(ii) 50-5% (wt) maleic anhydride,(iii) 0-20% (wt) acrylate,(iv) 0-20% (wt) acrylonitrile;B. 5-50% (wt) of an ethylene-propylene modified rubber or ethylene-propylene-diene modified rubber, the rubber being modified by grafting thereto a compound containing hydroxyl, amide or amine groups; andC. 0-30% (wt) of an ethylene-propylene rubber or an ethylene-propylene-diene rubber.

Abstract: A process for preparing an impact resistant thermoplastic moulding compound based on a copolymer consisting of styrene and/or .alpha.-methylstyrene and maleic anhydride by mixing:50-95% (wt) of a copolymer consisting of:(i) 50-95% (wt) styrene and/or .alpha.-methylstyrene,(ii) 50-5% (wt) maleic anhydride,(iii) 0-20% (wt) acrylate,(iv) 0-20% (wt) acrylonitrile;5-50% (wt) of a rubber modified with hydroxyl groups, a rubber modified with amine groups or a rubber modified with amide groups; and0-30% (wt) unmodified rubber,said mixing being conducted in the presence of 0.01-10 parts by weight of a reaction accelerator, calculated on 100 parts by weight copolymer and modified rubber, at a temperature between 160.degree. C. and 290.degree. C.

Abstract: Disclosed is an impact-resistant polymer composition based on a copolymer of an unsaturated nitrile, a substantially saturated rubber and a chlorinated polyethylene. To maintain high impact resistance while retaining good processing properties, the polymer composition comprises:A. 40-95 parts by weight of at least one copolymer obtained by polymerizing a mixture of:(1) 10-90 weight % of one or more monomers selected from the group consisting of styrene and derivatives thereof, and(2) 90-10 weight % of one or more monomers selected from the group containing of acrylonitrile and methacrylonitrile; andB. 5-60 parts by weight of a mixture comprising:(1) a substantially saturated rubber, and(2) chlorinated polyethylene having a chlorine content of from 32 to 45 weight %, a DSC crystallinity viscosity of at least 1.0, and wherein the weight ratio between rubber and chlorinated polyethylene is from 2:1 to 1:10.

Abstract: The invention relates to a polymer composition based on a copolymer of an unsaturated nitrile, a substantially saturated rubber, a chlorinated polyethylene, and a vinylchloride polymer.To improve the impact resistance and the flexural modulus, the polymer composition according to the invention comprises:a. 50-95 parts by weight of:a.1. 5-70 parts by weight of one or more polymers obtained by polymerizing a mixture of:10-90% wt. styrene and/or styrene derivatives,90-10% wt. acrylonitrile and/or methacrylonitrile, and0-20% wt. of one or more other monomers; anda.2. 95-30% vinylchloride polymer; andb. 5-50 parts by weight of:b.1. a substantially saturated rubber, andb.2. chlorinated polyethylene;with the vinylchloride polymer content in the overall polymer composition being at least about 25% by weight.

Abstract: An improved polymer composition having a combination of good flow behavior, UV stability, and very good impact resistance is described, essentially composed ofa. 50-95 parts by weight of one or more copolymers obtained by the polymerization of a mixture of10-90% by weight of acrylonitrile and/or methacrylonitrile; and,b. 5-50 parts by weight of1. a largely saturated rubber, and2. chlorinated polyethylene, wherein the chlorinated polyethylene has a chlorine content of 32-40% by weight, a DSC crystallinity of 0-7%, while the weight ratio of rubber to chlorinated polyethylene is between 2:1 and 1:10, i.e., from 0.1 to 2.

Abstract: An improved polymer composition having a combination of good flow behavior, UV stability, and very good impact resistance is described, essentially composed ofa.50-95 parts by weight of one or more copolymers obtained by the polymerization of a mixture of10-90% by weight of styrene and/or derivatives of styrene, with90-10% by weight of acrylonitrile and/or methacrylonitrile; andb.5-50 parts by weight of1. a largely saturated rubber, and2. chlorinated polyethylene, wherein the chlorinated polyethylene has a chlorine content of at least 10% by weight, a DSC crystallinity of at least 10% and a glass transition temperature of at least equal to -15.degree. C.

Abstract: A new elastomeric composition is described, having an improved combination of characteristics, which is composed of an intimate admixture of(a) 25-85% by weight of a substantially amorphous ethene-.alpha.-alkene copolymer, having a relatively low X-ray crystallinity of below about 4% by weight; and a tensile strength of at least 10 kg/cm.sup.2, and(b) 15-75% by weight of an at least partially crystalline block copolymer of propene and ethene, having an ethene content of between about 1 and 25% by weight and relatively high X-ray crystallinity of at least about 25% by weight.

Abstract: Polyfunctional anionic initiators for the preparation of elastomeric block copolymers are prepared by reacting a monofunctional anionic initiator, such as secondary butyl lithium, with a monovinyl aromatic compound, such as styrene, or a conjugated diene, such as butadiene or isoprene or mixtures thereof to form a polyuric reaction product which in turn, is reacted with a polyvinyl aromatic compound, such as divinyl benzene. The cross-linked reaction product, prior to use, is reacted with styrene or another monovinyl aromatic compound. The resulting polyfunctional anionic initiators are useful in producing elastomeric block co-polymers of the A-B-(A)n type exhibiting good elastomeric properties.

Abstract: An improved process for preparing elastomeric block copolymers of the formula A-B-A, wherein A is a poly-alpha-methyl-styrene polymer block, and B is an elastomeric polymer block from a conjugated diene. Alpha-methyl-styrene is polymerized by means of a mono-functional anionic initiator and an activator with an initial monomer concentration in excess of 100 g of alpha-methyl styrene per liter of reaction mixture, at a temperature of between 0.degree. and 40.degree.C, the amount of said activator being present such that the molar ratio of activator/initiator ranges from about 0.1 and 35 for a polymerization time of no more than 120 minutes. Thereafter, a small amount of conjugated diene and/or styrene is added to the reaction mixture. Subsequently, a conjugated diene is added to the mixture and polymerized. A bi-block copolymer consisting of a poly-alpha-methyl-styrene block and a poly (conjugated diene) block is formed.

Abstract: A method for preparing a block polymer A--B--C with alkyl lithium where the improvement is in the formation of block B. The method of forming block B which is a conjugated diene is carried out without the removal of contaminants.