A process for preparing a random copolymer based on at least one acyclic diene monomers and on at least one cyclic diene monomer is provided. The process comprises a step of copolymerization, in the presence of a polar agent and an anionic initiator in a polymerization solvent, of at least one acyclic diene monomer and of at least one cyclic diene monomer of which one CC double bond is endocyclic and conjugated to an exocyclic CC double bond, at a polymerization temperature below 80 C. A molar ratio of the polar agent/function(s) of the anionic initiator capable of initiating anionic polymrization being greater than 0.1.

Copolymers based on at least one acyclic diene monomer and on at least one cyclic diene monomer and the compositions containing them are also provided.

A hydrocarbon polymer modifier (HPM) is an interpolymer of (i) a vinyl cyclohexene component (ii) a piperylene component; and (iii) a C.sub.8-C.sub.12 vinyl aromatic component; and wherein the interpolymer comprises (a) a softening point from 40 C. to 160 C., (b) Mn greater than 400, (c) Mz less than 15,000, and (d) at least 8 mole percent aromatic hydrogen, based on the total moles of hydrogen in the interpolymer.

A hydrocarbon polymer modifier (HPM) is an interpolymer of (i) a vinyl cyclohexene component (ii) a piperylene component; and (iii) a C.sub.8-C.sub.12 vinyl aromatic component; and wherein the interpolymer comprises (a) a softening point from 40 C. to 160 C., (b) Mn greater than 400, (c) Mz less than 15,000, and (d) at least 8 mole percent aromatic hydrogen, based on the total moles of hydrogen in the interpolymer.

The present invention provides a rubber composition for tires which provides a balanced improvement in ice performance, fuel economy, and abrasion resistance, and a pneumatic tire containing the rubber composition. The present invention relates to a rubber composition for tires containing a rubber component including at least 80% by mass in total of at least one of an isoprene-based rubber, a polybutadiene rubber, or a styrene-butadiene rubber, the rubber composition containing, per 100 parts by mass of the rubber component, 10 to 120 parts by mass of silica, 0.2 to 10 parts by mass of a tetrazine compound of formula (1), and 1 to 50 parts by mass of a low-molecular-weight diene polymer having a weight average molecular weight of 200,000 or less.

The present invention provides a rubber composition for tires which provides a balanced improvement in ice performance, fuel economy, and abrasion resistance, and a pneumatic tire containing the rubber composition. The present invention relates to a rubber composition for tires containing a rubber component including at least 80% by mass in total of at least one of an isoprene-based rubber, a polybutadiene rubber, or a styrene-butadiene rubber, the rubber composition containing, per 100 parts by mass of the rubber component, 10 to 120 parts by mass of silica, 0.2 to 10 parts by mass of a tetrazine compound of formula (1), and 1 to 50 parts by mass of a low-molecular-weight diene polymer having a weight average molecular weight of 200,000 or less.

This invention relates to a process for the preparation of a polar-functionalized resin composition comprising the steps of (A) contacting a polymer backbone with a reactive moiety to produce a polar-functionalized resin composition wherein the polymer backbone is derived from a feed comprising less than or equal to about 35 wt % components derived from piperylene; less than or equal to about 10 wt % components derived from amylene; less than or equal to about 10 wt % components derived from isoprene; less than or equal to about 55 wt % unreactive paraffins; and C9 homopolymer or copolymer resins, in the presence of a Friedel-Crafts or Lewis acid catalyst; and (B) recovering a polar-functionalized resin composition.

The present invention provides an olefin-based polymer which satisfies the following conditions of (1) to (4) and is capable of exhibiting improved impact strength without degrading mechanical properties such as tensile strength: (1) density (d): from 0.850 to 0.910 g/cc, (2) melting index (MI, 190 C., 2.16 kg load conditions): from 0.1 to 100 g/10 min, (3) molecular weight distribution (MWD): from 1.5 to 3.0, and (4) two peaks are shown in a temperature range of 20 C. to 120 C. when taking measurements of temperature rising elution fractionation (TREF), and a relation of T(90)T(50)60 C. is satisfied (where T(90) is a temperature at which 90 wt % of the olefin-based polymer is eluted, and T(50) is a temperature at which 50 wt % of the olefin-based polymer is eluted).

Provided are a modified hydrocarbon resin that can provide a hot-melt adhesive composition with low odor, low Gardner color and high peel adhesion, a method for producing the resin, and the hot-melt adhesive composition. A modified hydrocarbon resin comprising a 1,3-pentadiene monomer unit, a C4-C6 alicyclic monoolefin monomer unit, a C4-C8 acyclic monoolefin monomer unit, an alicyclic diolefin monomer unit, and an aromatic monoolefin monomer unit, and containing a carboxyl group or acid anhydride group, wherein a weight average molecular weight (Mw), a Z average molecular weight (Mz), a ratio (Mz/Mw), a Gardner color scale of a 50 mass % toluene solution, a softening point, and an acid value are in specific ranges.

Provided are a modified hydrocarbon resin that can provide a hot-melt adhesive composition with low odor, low Gardner color and high peel adhesion, a method for producing the resin, and the hot-melt adhesive composition. A modified hydrocarbon resin comprising a 1,3-pentadiene monomer unit, a C4-C6 alicyclic monoolefin monomer unit, a C4-C8 acyclic monoolefin monomer unit, an alicyclic diolefin monomer unit, and an aromatic monoolefin monomer unit, and containing a carboxyl group or acid anhydride group, wherein a weight average molecular weight (Mw), a Z average molecular weight (Mz), a ratio (Mz/Mw), a Gardner color scale of a 50 mass % toluene solution, a softening point, and an acid value are in specific ranges.

The present invention is directed to a stereoregular functionalized elastomer represented by poly(M1 co M2), wherein the functionalized elastomer comprises a microstructure selected from the group consisting of microstructures having at least 90 percent by weight of monomer residues in trans 1,4-configuration, and microstructures having at least 80 percent by weight of monomer residues in cis 1,4-configuration; wherein M1 is selected from the group consisting of isoprene and 1,3-butadiene; and M2 is of formula 4 ##STR00001##
wherein R.sup.6 is a covalent bond, phenylene, a linear or branched alkane diyl group containing 1 to 10 carbon atoms, or a combination of one or more phenylene groups and one or more linear or branched alkane diyl groups containing 1 to 10 carbon atoms; R.sup.7 is hydrogen or a linear or branched alkyl group containing 1 to 10 carbon atoms; X.sup.1 is selected from formulas 5 and 6 ##STR00002##
wherein R.sup.8 and R.sup.9 are independently trialkylsilyl, phenyl or a linear or branched alkyl group containing 1 to 10 carbon atoms, or one of R.sup.8 and R.sup.9 is hydrogen and the other is phenyl or a linear or branched alkyl group containing 1 to 10 carbon atoms, or R.sup.8 and R.sup.9 taken together with the nitrogen atom represent a nitrogen containing heterocyclic group containing from 4 to 12 carbon atoms; and X.sup.2 is a sulfur atom or a structure of formula 7 or 8 ##STR00003##
wherein when X.sup.2 is of formula 8, the S atom of formula 8 is adjacent to the phenyl ring of formula 6 and the N atom of formula 8 is adjacent to R.sup.6.