A master batch includes a matrix resin containing a propylene-based resin and a non-volatile liquid with a boiling point of 200° C. or higher dispersed in the matrix resin. Temperature conditions represented by the relationships below are satisfied:

Tm<159° C.,

Tc≥97° C., and

Tm−Tc<49° C.

where Tc is a crystallization temperature indicated, in DSC measurement, as a peak top temperature of an exothermic peak observed on a highest temperature side when cooled to −50° C. at a temperature lowering speed of 10° C./min after heat treatment for 5 minutes at 200° C. and Tm is a melting point indicated, in the DSC measurement, as a peak top temperature of a melting peak observed on a highest temperature side when heated from −50° C. to 200° C. at a temperature rising speed of 10° C./min after being cooled.

The present invention relates to a hydrous silica for rubber reinforcing fillers having CTAB specific surface area in the range of 220 to 350 m.sup.2/g and a pore volume over the range of pore radius 1.9 to 100 nm measured by mercury press-in method in the range of 1.7 to 2.0 cm.sup.3/g, wherein a volume average particle diameter D50 in a volume particle size distribution measured by laser diffraction method for the slurry obtained by dispersing 50 ml of a hydrous silica slurry adjusted to 4 mass % with an ultrasonic homogenizer at an output of 140 W for 10 minutes is in the range of 5.0 to 12.0 μm, and a cumulative value of hydrous silica particles over the range of 4.0 to 35.0 μm in the volume particle size distribution is 80% or more. The present invention also relates to a rubber composition containing the above-mentioned hydrous silica and a rubber component containing a natural rubber. The present invention provides a hydrous silica which has equivalent or excellent reinforcing property (abrasion resistance, tensile strength) and which allows to greatly reduce the rolling resistance when it is blended into a rubber based on the natural rubber for TBRs, which is often used under a heavy load, compared with conventional hydrous silicas, and provides the rubber composition containing the hydrous silica.

The present invention relates to a hydrous silica for rubber reinforcing fillers having CTAB specific surface area in the range of 220 to 350 m.sup.2/g and a pore volume over the range of pore radius 1.9 to 100 nm measured by mercury press-in method in the range of 1.7 to 2.0 cm.sup.3/g, wherein a volume average particle diameter D50 in a volume particle size distribution measured by laser diffraction method for the slurry obtained by dispersing 50 ml of a hydrous silica slurry adjusted to 4 mass % with an ultrasonic homogenizer at an output of 140 W for 10 minutes is in the range of 5.0 to 12.0 μm, and a cumulative value of hydrous silica particles over the range of 4.0 to 35.0 μm in the volume particle size distribution is 80% or more. The present invention also relates to a rubber composition containing the above-mentioned hydrous silica and a rubber component containing a natural rubber. The present invention provides a hydrous silica which has equivalent or excellent reinforcing property (abrasion resistance, tensile strength) and which allows to greatly reduce the rolling resistance when it is blended into a rubber based on the natural rubber for TBRs, which is often used under a heavy load, compared with conventional hydrous silicas, and provides the rubber composition containing the hydrous silica.

In a first aspect, the present invention is directed to a rubber composition comprising 70 phr to 90 phr of styrene butadiene rubber, wherein said styrene butadiene rubber comprises a first styrene butadiene rubber having a glass transition temperature within a range of −49° C. to −15° C. and a second styrene butadiene rubber having a glass transition temperature within a range of −50° C. to −89° C. Furthermore, the rubber composition comprises from 10 phr to 30 phr of one or more of natural rubber and synthetic polyisoprene rubber, 100 phr to 200 phr of silica, and at least 25 phr of at least one terpene resin having a weight average molecular weight (Mw) of at most 1000 g/mol. Moreover, the invention is directed to a tire comprising such a rubber composition, in particular in the tread of the tire.

In a first aspect, the present invention is directed to a rubber composition comprising 70 phr to 90 phr of styrene butadiene rubber, wherein said styrene butadiene rubber comprises a first styrene butadiene rubber having a glass transition temperature within a range of −49° C. to −15° C. and a second styrene butadiene rubber having a glass transition temperature within a range of −50° C. to −89° C. Furthermore, the rubber composition comprises from 10 phr to 30 phr of one or more of natural rubber and synthetic polyisoprene rubber, 100 phr to 200 phr of silica, and at least 25 phr of at least one terpene resin having a weight average molecular weight (Mw) of at most 1000 g/mol. Moreover, the invention is directed to a tire comprising such a rubber composition, in particular in the tread of the tire.

A thermoplastic elastomer compound includes polyolefin elastomer, high softening point tackifier, and, optionally, styrenic block copolymer. When styrenic block copolymer is present, the weight ratio of polyolefin elastomer to styrenic block copolymer is no less than about 1:1. The polyolefin elastomer has a POE Tan Delta Peak Temperature, the styrenic block copolymer has a SBC Tan Delta Peak Temperature, and the thermoplastic elastomer compound has a Compound Tan Delta Peak Temperature. The Compound Tan Delta Peak Temperature is greater than the POE Tan Delta Peak Temperature. When styrenic block copolymer is present, Compound Tan Delta Peak Temperature is also greater than the SBC Tan Delta Peak Temperature. The thermoplastic elastomer compound exhibits useful damping properties at or above room temperature and can be formed into plastic articles, including foamed plastic articles and/or crosslinked plastic articles, which can be useful for a variety of damping applications.

A thermoplastic elastomer compound includes polyolefin elastomer, high softening point tackifier, and, optionally, styrenic block copolymer. When styrenic block copolymer is present, the weight ratio of polyolefin elastomer to styrenic block copolymer is no less than about 1:1. The polyolefin elastomer has a POE Tan Delta Peak Temperature, the styrenic block copolymer has a SBC Tan Delta Peak Temperature, and the thermoplastic elastomer compound has a Compound Tan Delta Peak Temperature. The Compound Tan Delta Peak Temperature is greater than the POE Tan Delta Peak Temperature. When styrenic block copolymer is present, Compound Tan Delta Peak Temperature is also greater than the SBC Tan Delta Peak Temperature. The thermoplastic elastomer compound exhibits useful damping properties at or above room temperature and can be formed into plastic articles, including foamed plastic articles and/or crosslinked plastic articles, which can be useful for a variety of damping applications.

The present application discloses compositions and methods for improving or enhancing the paving or re-paving of asphalt to road surfaces comprising the addition of the composition to the asphalt.

The present application discloses compositions and methods for improving or enhancing the paving or re-paving of asphalt to road surfaces comprising the addition of the composition to the asphalt.

A crosslinked rubber composition contains a rubber component and para-aramid short fibers having a filament fineness of 2.5 dtex or more and dispersed in the rubber component.