TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The fillers are soot, graphite, silicic acid, silicate, metal oxide, metal hydroxide, carbonate, sulfate, glass beads, diatomite, magnetic or magnetizable fillers, conductive fillers, fibers or organic fillers.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The component (b) is peroxide compound (preferably dicumyl peroxide, bis-(tert.butyl-peroxy-isopropyl)benzene, di-tert.butylperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethylhexine-2,5-dihydroperoxide, dibenzoylperoxide, bis-(2,4-dichlorobenzoyl)peroxide, tert.butylperbenzoate, tert.butylperoxyisobutyrate, tert.butylcumylperoxide, 2,5-dimethyl-2,5-di-(tert.butylperoxy)-hexane, 2,5-dimethyl-2,5-di-(tert.butylperoxy)hexyne(3), n-butyl-4,4'-di-(tert-butylperoxy)valerate, 1,1-di(tert-butylperoxy)-3,3,5-trimethyl-cyclohexane or 1,3-/1,4-bis(tert-butylperoxy-isopropyl)benzene), peroxy compound, alkyl-, aryl-, arenyl- and alkaryl-peroxide, diacyl peroxide, peroxydicarbonate, dialkyl peroxide, perester, peroxyketal, peroxyketone, hydroperoxide or azo compounds. The crosslinking activators are compounds that have at least one, two or more carbon-carbon double bonds (preferably 2,4,6-tris(allyloxy)-1,3,5-triazine, triallylisocyanurate, diallylmelamine, diisopropenylbenzene, divinylbenzene, divinylether, divinylsulfone, diallylphthalate, triallylcyanurate, triallylphosphate, N,N'-1,3-phenylene bismaleimide, 2,4-toluylenebis(maleimide), triallyltrimellitate, butadiene-oligomer or -polymer, 1,2-polybutadiene, 1,2-polybutadiene derivative, butadiene-styrene-copolymer, monoacrylate, diacrylate, triacrylate, trimethylpropane triacrylate, mono-methacrylate, dimethacrylate, trimethacrylate, trimethylolpropane trimethacrylate, triallylphosphonic acid ester, unsaturated polyester of aliphatic diol and polyol, maleic acid, fumaric acid and/or itaconic acid). The further additives are antiaging agents, antioxidants, ozone protecting agents, flame retardants, anti-hydrolysis agents, adhesion promoters, retardant agents and/or agents for reducing component stickiness, dyes and/or pigments, plasticizers or processing aids.    TECHNOLOGY FOCUS - POLYMERS - Preferred Composition: The composition comprises: 100 phr of (a), where at least 50 phr is low-viscous, completely or partially hydrogenated polyisoprene, and 0.1-15 phr of (b); or 100 phr of (a), 0.1-15 phr of (b), 0-800 phr of fillers, 0-30 phr of crosslinking activators for radical crosslinking, and optionally further additives. The composition, in addition to the completely or partially hydrogenated polyisoprene, comprises at least one additional rubber compound, which includes ethylene/propylene/diene-rubber, polybutadiene, hydrogenated or partially hydrogenated polybutadiene, ethylene/propylene rubber, polyisobutylene, halogenated butyl rubber, styrene/butadiene elastomer, polymethyl pentene, chloroprene rubber, halogenated rubber such as chlorinated or fluorinated polyethylene, ethylene/vinylacetate copolymer, acrylate rubber, nitrile rubber, hydrogenated nitrile rubber, non-hydrogenated and/or highly viscous polyisoprene or their copolymers and natural rubber. Preferred Components: The polyisoprene has an average molecular weight of 5000-100000 (preferably 10000-60000) g/mole. EXAMPLE - Typical composition comprised (in parts by weight per 100 parts by weight of rubber) of: liquid-ethylene propylene diene rubber (100); Aerosil R 8200 (RTM: A structure modified with hexamethyldisilazane aftertreated fumed silica) (30); and Luperox 101 XL 45 (RTM: 2,5-Dimethyl-2,5-di(tert-butyl peroxy)hexane) (5).