US 2006/0135671 A1 · Dual phase rubber composition and tire with nanocomposite-containing sidewall thereof

Abstract

This invention relates to a dual phase rubber composition and pneumatic tire with a rubber sidewall thereof, namely a dual phased non-black colored rubber composition composed of a first pre-formed elastomer phase comprised of butyl-type rubber and EPDM rubber containing a dispersion therein of reinforcing filler comprised of a particulate amorphous precipitated silica and a second pre-formed elastomer phase comprised of a nanocomposite of natural rubber containing a dispersion therein of exfoliated clay platelets. Said exfoliated clay platelets may be substantially oriented within the tire sidewall in a parallel direction to each and may also be substantially oriented in an annular direction about the axis of the tire. The tire sidewall rubber composition may contain at least one additional elastomer which may be included in either or both of said elastomer phases. Such tire sidewall rubber composition may contain a non-black colorant pigment, such as for example a white colored titanium dioxide pigment. The dual phased tire sidewall rubber composition is prepared by a phase mixing process comprised of pre-blending said butyl-type rubber and EPDM rubber together with said precipitated silica reinforcing filler to form a pre-mix thereof, and thereafter mixing therewith said nanocomposite as a pre-formed blend of natural rubber and exfoliated clay platelets.

Claims18

Dependent claims

A dual phase, non-black colored rubber composition comprised of a blend of a first elastomer phase and a second elastomer phase;

wherein said dual phase rubber composition is comprised of, based on parts by weight per 100 parts by weight rubber (phr):
(A) 100 phr of elastomers comprised of:
(1) about 40 to about 90 phr of a butyl-type rubber comprised of at least one of:
(a) butyl rubber comprised of a copolymer of isobutylene and about 0.5 to about 3 mole percent of conjugated diene comprised of isoprene,
(b) halogenated butyl rubber selected from chlorobutyl and bromobutyl rubber,
(c) brominated copolymer of isobutylene and para-methylstyrene,
(2) from zero to about 30 phr of EPDM rubber, and
(3) about 5 to about 50 phr of natural cis 1,4-polyisoprene rubber,
(B) about 5 to about 30 phr of precipitated silica reinforcing filler;
(C) partially exfoliated intercalated clay platelets as a dispersion in an amount of from about 5 to about 25 weight percent of a dispersion thereof in said natural cis 1,4-polyisoprene rubber (e.g. said natural cis 1,4-polyisoprene rubber contains a dispersion therein of from about 5 to about 25 weight percent of said partially exfoliated intercalated clay platelets), and
(D) a non-black colored pigment colorant, preferably comprised of titanium dioxide;
wherein said first elastomer phase is comprised of a pre-blend of said butyl-type rubber(s), said optional EPDM rubber and said precipitated silica;
wherein said second elastomer phase is a nanocomposite comprised of a pre-blend of said natural cis 1,4-polyisoprene rubber and said partially exfoliated intercalated clay platelets.

10 more elements

A pneumatic tire having an outer visible rubber sidewall of which at least a portion of said sidewall is a dual phased, non-black colored rubber composition, (therefore preferably exclusive of carbon black) comprised of a blend of a first elastomer phase and a second elastomer phase;

wherein said sidewall rubber composition is comprised of, based on parts by weight per 100 parts by weight rubber (phr):
(A) 100 phr of elastomers comprised of:
(1) about 40 to about 90 phr of a butyl-type rubber comprised of at least one of:
(a) butyl rubber comprised of a copolymer of isobutylene and about 0.5 to about 3 mole percent of conjugated diene comprised of isoprene,
(b) halogenated butyl rubber selected from chlorobutyl and bromobutyl rubber,
(c) brominated copolymer of isobutylene and para-methylstyrene,
(2) from zero to about 30 phr of EPDM rubber, and
(3) about 5 to about 50 phr of natural cis 1,4-polyisoprene rubber,
(B) about 5 to about 30 phr of precipitated silica reinforcing filler;
(C) partially exfoliated intercalated clay platelets as a dispersion in an amount of from about 5 to about 25 weight percent of a dispersion thereof in said natural cis 1,4-polyisoprene rubber (e.g. said natural cis 1,4-polyisoprene rubber contains a dispersion therein of from about 5 to about 25 weight percent of said partially exfoliated intercalated clay platelets), and
(D) a non-black colored pigment colorant, preferably comprised of titanium dioxide;
wherein said first elastomer phase is comprised of a pre-blend of said butyl-type rubber(s), said optional EPDM rubber and said precipitated silica;
wherein said second elastomer phase is a nanocomposite comprised of a pre-blend of said natural cis 1,4-polyisoprene rubber and said partially exfoliated intercalated clay platelets.

10 more elements

Dependencies are inferred from the claim text.

Dual phase rubber composition and tire with nanocomposite-containing sidewall thereof

Life of this patent

Dual phase rubber composition and tire with nanocomposite-containing sidewall thereof

Life of this patent

Abstract

Claims18