Low damping high strength polymer with long chain branching for use in anti-vibration applications
View Patent ↗A low damping high strength polymer with a blend of a terpolymer and a tetrapolymer utilizing ethylene, propylene, and non-conjugated dienes. This polymer allows for the creation of products with high diene contents and broad molecular weight distributions while utilizing a continuous flow reactor and a known catalyst. The polymer allows for these products to be made without gelling or fouling of the reactor, which are problems known in the art.
1. A low damping high strength ethylene propylene diene polymer comprising:
a. a tetrapolymer with the following characteristics:
(i) polymer chain branching as characterized by a tangent delta ranging from 0.15 to 0.75;
(ii) a non-linear relationship between viscosity and shear as characterized by the tangent delta from 0.15 to 0.75;
(iii) a weight average molecular weight from 500,000 to 2,500,000 Daltons;
(iv) a Mooney viscosity ranging from (ML 1+4@ 125 degrees Celsius) 50 to (ML 1+4@ 150 degrees Celsius) 215;
(v) an ethylene to a propylene ratio ranging from 40:60 to 80:20 by weight;
(vi) a molecular weight distribution ranging from 3.0 to 10;
(vii) a combined weight content of ethylene and the propylene of 50 percent to 80 percent based upon the total weight of the tetrapolymer;
(viii) a first non-conjugated diene content of 0.01 percent to 25 percent by weight content based upon the total weight of the tetrapolymer; and
(ix) a second non-conjugated diene of 0.01 percent to 5 percent by weight content based upon the total weight of the tetrapolymer;
b. a liquid phase ultrahigh molecular weight ENB EPDM terpolymer with the following characteristics:
(i) polymer chain branching as characterized by a tangent delta ranging from 1.0 to 0.75;
(ii) a non-linear relationship between viscosity and shear as characterized by the tangent delta from 1.0 to 0.75;
(iii) a weight average molecular weight from 700,000 to 2,500,000 Daltons;
(iv) a Mooney viscosity ranging from (ML 1+4@ 150 degrees Celsius) 80 to (ML 1+4@ 150 degrees Celsius) 215;
(v) an ethylene to propylene ratio ranging from 65:35 to 75:25 by weight;
(vi) a molecular weight distribution ranging from 2.0 to 2.5;
(vii) a combined weight content of ethylene and the propylene of 93 percent to 97 percent based upon the total weight of the ENB EPDM terpolymer; and
(viii) a first non-conjugated diene content of 3 percent to 7 percent by weight content based upon the total weight of the ENB EPDM terpolymer; and
wherein the tetrapolymer is continuously blended with the ultrahigh molecular weight ENB EPDM terpolymer forming the low damping high strength ethylene propylene diene polymer.
2. The low damping high strength ethylene propylene diene polymer of claim 1 , comprising:
a. 75 to 45 weight percent of the liquid phase tetrapolymer;
b. 3 weight percent to 5 weight percent of a first solvent;
c. 25 weight percent to 55 weight percent the liquid phase ultrahigh molecular weight ENB EPDM terpolymer; and
d. 3 weight percent to 5 weight percent of a second solvent based on the total weight of the formed low damping high strength ethylene propylene diene polymer.
3. The low damping high strength ethylene propylene diene polymer of claim 1 , comprising: 0.1 to 0.5 weight percent of an antioxidant added to low damping high strength ethylene propylene diene polymer.
4. The low damping high strength ethylene propylene diene polymer of claim 1 , wherein the first non-conjugated diene and the second non-conjugated diene are both norbornene derivatives.
5. The low damping high strength ethylene propylene diene polymer of claim 4 , wherein the second non-conjugated diene is a vinyl norbornene.
6. The low damping high strength ethylene propylene diene polymer of claim 1 , further comprising an extender oil.