Patent ID: 6172138
Filing Date: 2001-01-09
Classification: B29B,C08J,C08K,Y10T

Abstract:
A method of preparing an elastomer/filler composite as a dispersion of a filler formed in-situ within an elastomer host which comprises blending, in an internal mixer, a filler precursor, condensation reaction promoter and elastomer host selected from at least one of the group consisting of elastomer host (A) and elastomer host (B), to initiate a condensation reaction of said filler precursor and, for elastomer host (A), and optionally for elastomer host (B), subsequently adding and reacting, in an internal mixer, an organosilane material with said filler/filler precursor prior to the completion of said condensation reaction; followed by recovering the resulting elastomer/filler composite;wherein said elastomer host (A) is selected from at least one of the group consisting of homopolymers of conjugated dienes, copolymers of conjugated dienes and copolymers of conjugated diene with a vinyl aromatic compound selected from styrene and alphamethyl styrene; wherein said elastomer host (B) is selected from at least one alkoxy metal end functionalized diene-based elastomer wherein said metal is selected from silicon, titanium, aluminum or boron, and wherein said elastomer is selected from at least one of the group consisting of homopolymers of conjugated dienes, copolymers of conjugated dienes and copolymers of conjugated diene with a vinyl aromatic compound selected from styrene and alpha-methylstyrene;wherein said filler precursor is at least one material selected from the formulas (IIA), (IIB) and (IIC):M(OR).sub.x (R').sub.y (IIA)(RO).sub.x (R').sub.y M--O--M'(R').sub.z (RO).sub.w (IIB)(RO).sub.x (R').sub.y M--(CH.sub.2).sub.x --M'(R').sub.z (RO).sub.w (IIC)wherein M and M' are the same or different and are selected from silicon, titanium, zirconium, boron and aluminum, where R and R' are alkyl radicals individually selected from methyl, ethyl, n-propyl, isopropyl, n-butyl and isobutyl radicals, wherein x and w are individually equal to at least two, and wherein the sum of the integers x+y and w+z depend upon the valence of the associated M or M' as the case may be, whereby for formula (IIA) the sum of the integers x+y is therefore equal to 4 except when its associated M or M' is boron or aluminum for which it is 3; and wherein r is from 1 to 15;wherein said organosilane is at least one material selected from formula (III), (IV) and (V), namely:an organosilane polysulfide of Formula (III) as:Z--R.sup.1 --S.sub.m --R.sup.1 --Z (III)wherein m is a number in a range of from 2 to about 8 and the average for m is in a range of (a) about 2 to about 2.6 or (b) about 3.5 to about 4.5;wherein Z is represented by the following formulas: ##STR2##wherein R.sup.2 is the same or different radical and is individually selected from alkyl radicals having 1 to 4 carbon atoms and phenyl radical; R.sup.3 is the same or different alkoxy groups wherein the alkyl radicals of the alkoxy group(s) are alkyl radicals selected from methyl, ethyl, n-propyl, isopropyl, n-butyl and isobutyl radicals; and R.sup.1 is a radical selected from the group consisting of a substituted or unsubstituted alkyl radicals having a total of 1 to 18 carbon atoms and a substituted or unsubstituted aryl radical having a total of 6 to 12 carbon atoms;an alkyl alkoxy silane of Formula (IV) as:(OR.sup.4).sub.3 --Si--R.sup.5 (IV)where R.sup.4 may be the same or different alkyl radical selected from methyl, ethyl, n-propyl and isopropyl radicals and R.sup.5 is selected from alkyl radicals having from 1 to 18 carbon atoms and aryl radicals or alkyl substituted aryl radicals having from 6 to 12 carbon atoms; anda functional organosilane of Formula (V) as:(OR.sup.6).sub.3 --Si--(CH.sub.2).sub.y --Y (V)wherein R.sup.6 is the same or different alkyl radicals selected from methyl, ethyl, n-propyl and isopropyl radicals, y is an integer of from 1 to 12, and Y is selected from primary amino, mercapto, epoxide, thiocyanato, vinyl, methacrylate, ureido, isocyanato and ethylene diamine radicals.