Abstract: A vulcanizable rubber mixture for producing a leather-hard rubber, which mixture is suitable for use in making a composite profile produced by simultaneous extrusion and vulcanization of two different grades of rubber. The composite profile has a region of leather-hard rubber which serves as the clamping part, and a second zone made integrally therewith, of ordinary soft, rubber-elastic rubber. The vulcanizable rubber mixture for producing a leather-hard mixture contains 20 to 40 parts by weight of polar rubber, i.e. rubber which splits off acid groups under vulcanizing conditions, e.g. polychloroprene, and 60 to 80 parts non-polar rubber, i.e. will not split off said groups, e.g. nitrile rubber, 15 to 50 parts phenolformaldehyde reinforcement resin, 0.5 to 4 parts hexamethylene tetramine, and 0.5 to 3 parts sulfur. Conventional accelerators and zinc oxide are added.

Abstract: Mixtures of(1) 99 to 1% of one or more segment copolymers of alternating linear or branched segments A and B wherein A are polymer blocks of aromatic vinyl compounds with Tg>20.degree. C. (hard segment) and B are polymer blocks containing polymerized conjugated dienes with Tg>0.degree. C. (soft segment), and(2) 1 to 99% of one or more aromatic polycarbonates in which the linear chains consist to an extent of at least 50% of structural units of the formula ##STR1## wherein X=C.sub.1 -C.sub.5 alkylene or alkylidene.

Abstract: Branched polymers being producible by reacting an anion of a branched aromatic vinyl/diene block polymer with an aromatic polycarbonate or with a mixture of aromatic polycarbonates wherein at least 50% of the linear chains of the polycarbonate or mixture of polycarbonates consist of structural units corresponding to the Formula (1) ##STR1## in which X represents a C.sub.1 -C.sub.5 -alkylene or C.sub.1 -C.sub.5 -alkylidene radical.

Abstract: A freeflowing rubber mixture which is stable against coalescence and cohesion comprising a vulcanizable rubber in powder form and a minor amount of an acrylonitrile polymer as a separating agent.

Abstract: For the short-duration determination of the flowability of rubber powder after storage, the rubber powder is poured into a cylindrical container in which is immersed a resistance element. This element displays an analogue value via a torque measuring device when there is relative rotation between the container and the resistance element.

Abstract: A segment polymer comprising units derived from a linear living aromatic vinyl-diene block polymer anion and from an aromatic polycarbonate in which at least 50% of the polycarbonate consist of structural units represented by the following formula (I): ##STR1## wherein X denotes C.sub.1 -C.sup.5 alkylene or alkylidene, AND WHICH HAS THERMOPLASTIC AND ELASTOMERIC PROPERTIES.

Abstract: A mixture of polyolefin resins and partially crosslinked ethylene-propylene sequential polymer and/or ethylene-propylene-diene sequential polymer representing a so-called thermoplastic rubber having improved properties.