Provided is a fluorosilicone resin and a preparation method thereof. Using pentafluorostyrene as raw material, pentafluorophenethyldimethylchlorosilane is prepared by a hydrosilylation reaction. By means of a polycondensation reaction of the pentafluorophenethyldimethylchlorosilane, trimethylchlorosilane and tetraethyl orthosilicate, a pentafluorophenyl silicone resin is prepared. The preparation method adopts a two-step polycondensation process, which overcomes the disadvantages of a large difference in hydrolysis reactivity between pentafluorophenyldimethylchlorosilane and a copolymerized trialkyl-chlorosilane, and achieves a high yield. The obtained pentafluorophenyl silicone resin has the advantages of superior heat resistance, simple preparation process, low equipment requirements, high availability of raw material, and suitability for mass production. The heat-resistant fluorosilicone resin can be applied in a polymer material, such as a heat-resistant adhesive.

A rubber composition including 100 parts by mass of a diene rubber containing natural rubber, and blended with from 40 to 80 parts by mass of carbon black, cobalt neodecanoate borate represented by the following Chemical Formula (1), a phenolic resin, a curing agent, sulfur, and a vulcanization accelerator, wherein the carbon black has DBP oil absorption of from 50×10.sup.−5 to 80×10.sup.−5 m.sup.3/kg, and iodine adsorption of from 100 to 150 g/kg, and a vulcanized rubber has characteristics of a dynamic storage modulus (E′) at a dynamic strain of 2% and at 20° C. of 8 MPa or more, a tangent loss (tan δ) at 60° C. of 0.20 or less, and the number of times of repetition until fracture is caused in a constant strain fatigue test at a strain of 60% and at 400 rpm of 45,000 or more. ##STR00001##

A rubber composition including 100 parts by mass of a diene rubber containing natural rubber, and blended with from 40 to 80 parts by mass of carbon black, cobalt neodecanoate borate represented by the following Chemical Formula (1), a phenolic resin, a curing agent, sulfur, and a vulcanization accelerator, wherein the carbon black has DBP oil absorption of from 50×10.sup.−5 to 80×10.sup.−5 m.sup.3/kg, and iodine adsorption of from 100 to 150 g/kg, and a vulcanized rubber has characteristics of a dynamic storage modulus (E′) at a dynamic strain of 2% and at 20° C. of 8 MPa or more, a tangent loss (tan δ) at 60° C. of 0.20 or less, and the number of times of repetition until fracture is caused in a constant strain fatigue test at a strain of 60% and at 400 rpm of 45,000 or more. ##STR00001##

A rubber composition which comprises at least 50 phr of a copolymer of ethylene and of a 1,3-diene which contains at least 50 mol % of ethylene units, a carbon black and a vulcanizing system comprising sulfur and a vulcanization accelerator which is a mixture of a primary accelerator and of a secondary accelerator is provided. The mass ratio between the amount of secondary accelerator and the total amount of accelerators is less than 0.7. Such a composition has a good compromise between the cohesion and curing properties.

A rubber composition which comprises at least 50 phr of a copolymer of ethylene and of a 1,3-diene which contains at least 50 mol % of ethylene units, a carbon black and a vulcanizing system comprising sulfur and a vulcanization accelerator which is a mixture of a primary accelerator and of a secondary accelerator is provided. The mass ratio between the amount of secondary accelerator and the total amount of accelerators is less than 0.7. Such a composition has a good compromise between the cohesion and curing properties.

The present invention relates to adhesive mixtures containing resorcinol and/or resorcinol esters, melamine formaldehyde ethers and sulfenamide derivatives and also silica for use in rubbers, to the production thereof, to vulcanizates and composite articles produced therefrom and to the use thereof.

The present invention relates to adhesive mixtures containing resorcinol and/or resorcinol esters, melamine formaldehyde ethers and sulfenamide derivatives and also silica for use in rubbers, to the production thereof, to vulcanizates and composite articles produced therefrom and to the use thereof.

The present invention relates to a vulcanizable elastomeric composition comprising a secondary accelerator that may be used in combination with sulphenamide alone, completely avoiding the use of a guanidine. Moreover, said accelerator promotes dispersion of the silica in the compound and migrates with difficulty in the elastomeric composition itself. The invention also relates to the use of a vulcanization accelerator for said elastomeric composition, to the associated vulcanization process and to a tyre comprising same.

The present invention relates to a vulcanizable elastomeric composition comprising a secondary accelerator that may be used in combination with sulphenamide alone, completely avoiding the use of a guanidine. Moreover, said accelerator promotes dispersion of the silica in the compound and migrates with difficulty in the elastomeric composition itself. The invention also relates to the use of a vulcanization accelerator for said elastomeric composition, to the associated vulcanization process and to a tyre comprising same.

An organic silicon compound represented by formula (1) makes it possible to significantly lower the hysteresis loss of a cured product when added to a rubber composition and also imparts a rubber composition with which it is possible to realize a desired low-fuel-consumption tire. ##STR00001##
(In the formula, R.sup.1 independently represent a C1-10 alkyl group or C6-10 aryl group, R.sup.2 independently represent a C1-10 alkyl group or C6-10 aryl group, f represents a number of 0 or higher, e and g independently represent a number greater than 0, and m represents an integer of 1-3. However, the order of each of the repeating units is arbitrary.)