Embodiments of the present disclosure describe a method of synthesizing a polymer comprising contacting a first monomer and an organolithium initiator in a nonpolar solvent and adding a promoter to the nonpolar solvent to polymerize the first monomer. Embodiments of the present disclosure further describe a method of synthesizing a polymer comprising contacting a first monomer and an organolithium initiator in a nonpolar solvent, adding a promoter to the nonpolar solvent to polymerize the first monomer, and adding a second monomer to the nonpolar solvent to polymerize the second monomer.

A star block copolymer and a thermoplastic elastomer including plurality of the star block copolymers and a method of making both is taught. The star block copolymers of the present invention include a core component having a styrene oligomer wherein arms emanate from the core component and the arms are poly(isobutylene-block-styrene) diblock copolymers.

A star block copolymer and a thermoplastic elastomer including plurality of the star block copolymers and a method of making both is taught. The star block copolymers of the present invention include a core component having a styrene oligomer wherein arms emanate from the core component and the arms are poly(isobutylene-block-styrene) diblock copolymers.

Polar silane linkers are provided that attach to resins to form silane-functionalized resins. The functionalized resins can be bound to hydroxyl groups on the surface of silica particles to improve the dispersibility of the silica particles in rubber mixtures. Further disclosed are synthetic routes to provide the silane-functionalized resins, as well as various uses and end products that benefit from the unexpected properties of the silane-functionalized resins. Silane-functionalized resins impart remarkable properties on various rubber compositions, such as tires, belts, hoses, brakes, and the like. Automobile tires incorporating the silane-functionalized resins are shown to possess excellent results in balancing the properties of rolling resistance, tire wear, and wet braking performance.

Polar silane linkers are provided that attach to resins to form silane-functionalized resins. The functionalized resins can be bound to hydroxyl groups on the surface of silica particles to improve the dispersibility of the silica particles in rubber mixtures. Further disclosed are synthetic routes to provide the silane-functionalized resins, as well as various uses and end products that benefit from the unexpected properties of the silane-functionalized resins. Silane-functionalized resins impart remarkable properties on various rubber compositions, such as tires, belts, hoses, brakes, and the like. Automobile tires incorporating the silane-functionalized resins are shown to possess excellent results in balancing the properties of rolling resistance, tire wear, and wet braking performance.

Polar silane linkers are provided that attach to resins to form silane-functionalized resins. The functionalized resins can be bound to hydroxyl groups on the surface of silica particles to improve the dispersibility of the silica particles in rubber mixtures. Further disclosed are synthetic routes to provide the silane-functionalized resins, as well as various uses and end products that benefit from the unexpected properties of the silane-functionalized resins. Silane-functionalized resins impart remarkable properties on various rubber compositions, such as tires, belts, hoses, brakes, and the like. Automobile tires incorporating the silane-functionalized resins are shown to possess excellent results in balancing the properties of rolling resistance, tire wear, and wet braking performance.

Polar silane linkers are provided that attach to resins to form silane-functionalized resins. The functionalized resins can be bound to hydroxyl groups on the surface of silica particles to improve the dispersibility of the silica particles in rubber mixtures. Further disclosed are synthetic routes to provide the silane-functionalized resins, as well as various uses and end products that benefit from the unexpected properties of the silane-functionalized resins. Silane-functionalized resins impart remarkable properties on various rubber compositions, such as tires, belts, hoses, brakes, and the like. Automobile tires incorporating the silane-functionalized resins are shown to possess excellent results in balancing the properties of rolling resistance, tire wear, and wet braking performance.

A polypropylene comprising a xylene soluble fraction of 1.5 wt % by weight of the polymer and soluble fraction or less, wherein the polypropylene has a melt flow rate within a range from 50 g/10 min to 500 g/10 min and a flexural modulus within a range from 1780 MPa to 2200 MPa. The polypropylene is preferably made from contacting propylene with a solid magnesium/titanium catalyst component that has been washed at least once with a solvent having a desirable solubility parameter.

A Brønsted-Lowry acid initiator system for cationic polymerization of an ethylenically unsaturated monomer involves an initiator having a structure of Formula (I) in an anhydrous polymerization medium:

##STR00001## where: M is tantalum (Ta), vanadium (V) or niobium (Ni); R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are the same or different and are independently H, F, Cl, Br, I, alkyl or aryl, or two or more of R.sub.2, R.sub.3, R.sub.4 and R.sub.5 on a same benzene ring are taken together to form a bicyclic, tricyclic or tetracyclic moiety with the benzene ring, with the proviso that all of R.sub.1, R.sub.2, R.sub.3 and R.sub.4 on the same benzene ring are not H; L is absent or a molecule that coordinates to H.sup.+; and, x is 0 when L is absent, or x is 0.5 or more when L is present.

A Brønsted-Lowry acid initiator system for cationic polymerization of an ethylenically unsaturated monomer involves an initiator having a structure of Formula (I) in an anhydrous polymerization medium:

##STR00001## where: M is tantalum (Ta), vanadium (V) or niobium (Ni); R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are the same or different and are independently H, F, Cl, Br, I, alkyl or aryl, or two or more of R.sub.2, R.sub.3, R.sub.4 and R.sub.5 on a same benzene ring are taken together to form a bicyclic, tricyclic or tetracyclic moiety with the benzene ring, with the proviso that all of R.sub.1, R.sub.2, R.sub.3 and R.sub.4 on the same benzene ring are not H; L is absent or a molecule that coordinates to H.sup.+; and, x is 0 when L is absent, or x is 0.5 or more when L is present.