Nanostructed polymers on the basis of conjugated dienes
View Patent ↗The present invention relates to nano-structured diene polymers and their preparation and to their use.
1. A polymer obtained by polymerization of a conjugated diene with a catalyst of the rare earths, whereby an intermediate polymer is formed and subsequently reacted with an oligomeric silicates of the formula X 3 —Si—(O—SiX 2 ) n —X, where
X is an alcoholate of the formula OR,
R is a saturated or partially unsaturated aliphatic hydrocarbon radical having from 1 to 30 carbon atoms, a cycloaliphatic hydrocarbon radical having from 5 to 30 carbon atoms, or an aromatic hydrocarbon radical having from 6 to 30 carbon atoms, and
n is a number greater than 0,
thereby forming the polymer, wherein the polymer has a bimodal molar mass distribution comprising a high molecular-weight fraction and a low molecular-weight fraction, wherein the high-molecular-weight fraction has a number average molar mass (M n ) greater than 2,000,000 g/mol, the amount of the high-molecular-weightfraction, based on the polymer, is in the range from 1% to 20%, and the content of 1,2-vinyl units, based on the polymer, is from 0.3 to 1% by weight.
2. The polymer according to claim 1 , wherein the conjugated diene comprises 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 3-butyl-1,3-octadiene, isoprene, piperylene, 1,3-hexadiene, 1,3-octadiene and/or 2-phenyl-1,3-butadiene.
3. A process comprising:
polymerizing a conjugated diene in the presence of an inert organic, aprotic solvent and in the presence of a catalyst of the rare earths, whereby an intermediate polymer is obtained,
reacting the intermediate polymer with an oligomeric silicate of the formula X 3 —Si—(O—SiX 2 ) n —X, where
X is an alcoholate of the formula OR,
R is a saturated or partially unsaturated aliphatic hydrocarbon radical having from 1 to 30 carbon atoms, a cycloaliphatic hydrocarbon radical having from 5 to 30 carbon atoms or an aromatic hydrocarbon radical having from 6 to 30 carbon atoms, and
n is a number greater than 0, and
wherein the amount of the oligomeric silicate used in relation to polymers is in the range from 0.001 to 10 g:100 g.