According to the process for preparing a vulcanized rubber composition of the invention comprising (a) a step of preparing a master batch comprising a butadiene rubber and silica, (b) a step of preparing a master batch comprising an isoprene rubber and silica, (c) a step of kneading the master batch obtained in (a) and the master batch obtained in (b), and (d) a step of vulcanizing a kneaded product obtained in (c), wherein the obtained vulcanized rubber composition has a BR phase and a IR phase which are incompatible with each other and comprises a predetermined amount of a terpene resin, a predetermined abundance ratio α of silica in the BR phase satisfies 0.3≦α≦0.7 (Relation 1), and a proportion β of the butadiene rubber satisfies 0.4≦β≦0.8 (Relation 2) it is possible to improve performance on ice, wet performance and abrasion resistance in good balance and to provide a vulcanized rubber composition having excellent performance on ice, wet performance and abrasion resistance, and a studless tire with a tread made using the same.

A method for producing a rubber composition, which comprises kneading 20 parts by mass or more of silica with 100 parts by mass of diene rubber, and adding from 3 to 20 parts by mass of syndiotactic-1,2-polybutadiene to the kneaded mixture obtained, followed by kneading is disclosed. This method brings out characteristics of syndiotactic-1,2-polybutadiene and can improve wet grip performance.

The present technology provides an epoxy resin composition for a fiber-reinforced composite material, a method for producing an epoxy resin composition for a fiber-reinforced composite material, a prepreg, and a honeycomb panel. The epoxy resin composition for a fiber-reinforced composite material of the present technology contains: a reaction product obtained by reacting 100 parts by mass of a phosphorus-containing epoxy resin containing a phosphorus atom in the backbone thereof, and not less than 5 parts by mass and not greater than 20 parts by mass of an amino-terminated butadiene-acrylonitrile rubber; an epoxy resin other than the phosphorus-containing epoxy resin; a curing agent; and a curing accelerator.

An airless tire has a tread ring provided with a reinforcing rubber layer disposed radially inside a tread rubber layer and made of a rubber compound [A] comprising: 100 parts by mass of the rubber component containing 10 to 100% by mass of butadiene rubber; 10 to 80 parts by mass of an metal salt of an alpha beta unsaturated carboxylic acid; and a peroxide. A barrier layer, which restrains sulfur in an adjacent rubber compound from migrating into the reinforcing rubber layer, is disposed between the reinforcing rubber layer and the adjacent rubber compound.

The instant invention relates to rubber compositions comprising silica, an organosilane having at least one cyclic and/or bridged alkoxy group and a rosin-containing material. The instant invention also relates to tires comprising such rubber compositions, to methods of preparation of such rubber compositions or tires thereof, and to the use of rosin-containing materials for improving the Mooney viscosity of rubbers comprising the same (e.g. in a tire).

A method for preparing a vulcanizable composition of matter, the method comprising mixing rubber, silica, silica coupling agent, a strong base, and nicotinamide to form a masterbatch, introducing a curative to the masterbatch, and mixing the curative into the masterbatch to form a vulcanizable composition of matter.

The present invention relates to a cross-linkable rubber composition, a cross-linked rubber composition obtained by cross-linking such a rubber composition, a method of preparing a tyre and a tyre. A cross-linkable rubber composition comprises, per hundred parts by weight of rubber (phr): ≧1 phr to ≦99 phr of a styrene-butadiene rubber (SBR) component; ≧1 phr to ≦99 phr of a polybutadiene rubber (BR) component; ≧5 phr to ≦35 phr of a polyterpene resin component;

The polybutadiene rubber has a branching index G of ≧0.7 to ≦0.85 and a polydispersity index Mw/Mn of ≧3.5 and ≦4.5 and the polyterpene resin has a molecular weight Mw of ≧900 to ≦1200.

According to the process for preparing a vulcanized rubber composition of the invention comprising (a) a step of preparing a master batch comprising a modified conjugated diene polymer and silica, (b) a step of preparing a master batch comprising an isoprene rubber and silica, (c) a step of kneading the master batch obtained in (a) and the master batch obtained in (b), and (d) a step of vulcanizing a kneaded product obtained in (c), wherein the obtained vulcanized rubber composition comprises a phase A comprising a modified conjugated diene polymer and a phase B comprising an isoprene rubber, which are incompatible with each other, an abundance ratio α of silica in the phase A satisfies 0.5≦α≦0.9 (Relation 1), and a proportion β of the modified conjugated diene polymer satisfies 0.4≦β≦0.8 (Relation 2) it is possible to improve performance on ice and abrasion resistance and to provide a vulcanized rubber composition having excellent performance on ice and abrasion resistance, and a studless tire with a tread made using the same.

A polymeric compound involves a blend of 50 wt % or greater of a thermoplastic having an average melting point (T.sub.m) of less than 200 ° C. and less than 50 wt % of a butyl rubber ionomer dispersed in a matrix of the thermoplastic, weights based on total weight of the thermoplastic and butyl rubber ionomer. Such blends may exhibit improved physical properties compared to unblended thermoplastic, particularly ultimate elongation and/or damping. The polymeric compounds are useful for forming a variety of articles of manufacture.

According to a production method of a rubber composition for tire of the present invention comprising a rubber component (A) comprising at least one selected from the group consisting of a natural rubber and a synthetic diene rubber, a filler, a coupling agent (D) of (C.sub.pH.sub.2p+1O).sub.3—Si—(CH.sub.2).sub.q—S—CO—C.sub.kH.sub.2k+1, and a vulcanizing agent (E) comprising a vulcanizer and a vulcanization accelerator, the method comprising: a step X1 of kneading all amount of A, a part of the filler and a part of D, a step X2 of kneading the kneaded product of step X1, the remaining amount of the filler and D, and a step F of kneading the kneaded product of step X2 and E, it is possible to produce a rubber composition for tire in which fuel efficiency and abrasion resistance are improved in a good balance.