Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
236 words
A process for preparing a styrene-isoprene-butadiene rubber which is particularly valuable for use in making truck tire treads which comprises the steps of (1) continuously solution terpolymerizing in an organic solvent from about 5 weight percent to about 20 weight percent styrene, from about 7 weight percent to about 35 weight percent isoprene, and from about 55 weight percent to about 88 weight percent 1,3-butadiene, based on total monomers, to a conversion which is in the range of about 60% to about 100% to produce a living intermediate polymer, wherein the terpolymerization is initiated with an organolithium compound, wherein the terpolymerization is conducted in the presence of 10 ppm to 500 ppm of 1,2-butadiene, and wherein the terpolymerization is conducted in the presence of N,N,N',N'-tetramethylethylenediamine at a molar ratio of N,N,N',N'-tetramethylethylenediamine to the organolithium compound which is within the range of about 0.01:1 to about 0.2:1, and wherein the terpolymerization is conducted at a temperature which is within the range of about 75° C. to about 150° C.; (2) partially coupling the living intermediate polymer with a coupling agent selected from the group consisting of divinyl benzene, tin tetrachloride and silicon tetrachloride, wherein the molar ratio of the organolithium compound to the coupling agent is within the range of about 6:1 to about 20:1; (3) allowing the terpolymerization to continue so as to produce the styrene-isoprene-butadiene rubber; and recovering the styrene-isoprene-butadiene rubber from the organic solvent.
Claim 2
Dependent Claim
236 words
A process for preparing a styrene-isoprene-butadiene rubber which is particularly valuable for use in making truck tire treads which comprises the steps of (1) continuously solution terpolymerizing in an organic solvent from about 5 weight percent to about 20 weight percent styrene, from about 7 weight percent to about 35 weight percent isoprene, and from about 55 weight percent to about 88 weight percent 1,3-butadiene, based on total monomers, to a conversion which is in the range of about 60% to about 100% to produce a living intermediate polymer, wherein the terpolymerization is initiated with an organolithium compound, wherein the terpolymerization is conducted in the presence of 10 ppm to 500 ppm of 1,2-butadiene, and wherein the terpolymerization is conducted in the presence of N,N,N',N'-tetramethylethylenediamine at a molar ratio of N,N,N',N'-tetramethylethylenediamine to the organolithium compound which is within the range of about 0.01:1 to about 0.2:1, and wherein the terpolymerization is conducted at a temperature which is within the range of about 75° C. to about 150° C.; (2) partially coupling the living intermediate polymer with a coupling agent selected from the group consisting of divinyl benzene, tin tetrachloride and silicon tetrachloride, wherein the molar ratio of the organolithium compound to the coupling agent is within the range of about 6:1 to about 20:1; (3) allowing the terpolymerization to continue so as to produce the styrene-isoprene-butadiene rubber; and recovering the styrene-isoprene-butadiene rubber from the organic solvent.
Claim 3
Dependent Claim
28 words
A process as specified in claim 1 wherein step (1) is carried out in a first reactor and wherein step (2) is carried out in a second reactor.
Claim 4
Dependent Claim
27 words
A process as specified in claim 2 wherein the 1,2-butadiene is present at a level which is within the range of about ppm to about 300 ppm.
Claim 5
Dependent Claim
26 words
A process as specified in claim 3 wherein the molar ratio of N,N,N',N'-tetramethylethylenediamine to organolithium initiator is within the range of about 0.05:1 to about 0.15:1.
Claim 6
Dependent Claim
29 words
A process as specified in claim 4 wherein the molar ratio of the organolithium initiator to the coupling agent is within the range of about 8:1 to about 12:1.
Claim 7
Dependent Claim
28 words
A process as specified in claim 5 wherein the 1,2-butadiene is present at a level which is within the range of about 100 ppm to about 200 ppm.
Claim 8
Dependent Claim
15 words
A process as specified in claim 2 wherein the organolithium compound is an organomonolithium compound.
Claim 9
Dependent Claim
26 words
A process as specified in claim 4 wherein the living intermediate polymer is partially coupled after a monomer conversion of 72% to 90% has been attained.
Claim 10
Dependent Claim
23 words
A process as specified in claim 5 wherein the coupling agent is selected from the group consisting of tin tetrachloride and silicon tetrachloride.