Ethylene propylene diene monomer (EPDM) and vinyl norbornene diene (VNB) copolymers and methods of making same
Disclosed herein are EPDM-VNB copolymers that have a low molecular weight and are liquid at room temperature. The copolymers include: ethylene, propylene, and vinyl norbornene, where the copolymers have a molecular weight from about 2,500 g/mol to about 1,000,000 g/mol, and where the copolymers have a viscosity from about 1,000 cP to about 2,500,000 cP at 100° C.
1. A copolymer comprising:
ethylene;
propylene; and
vinyl norbornene, wherein the copolymer has a weight-average molecular weight from about 2,500 g/mol to about 1,000,000 g/mol, wherein the copolymer has a propylene content of at least 50 wt %, wherein a vinyl norbornene content of the copolymer is at least 8.0 wt % of the copolymer, and wherein the copolymer has a viscosity from about 1,000 cP to about 2,500,000 cP at 100° C.
2. The copolymer of claim 1 , wherein the copolymer has an ethylene:propylene ratio from about 40:60 to about 80:20.
3. The copolymer of claim 1 , wherein the copolymer has a number-average molecular weight of less than 50,000 g/mol.
4. The copolymer of claim 1 , wherein the copolymer has an ethylene content from about 5 wt % to about 48 wt %.
5. The copolymer of claim 1 , wherein the copolymer is a liquid at room temperature.
6. The method of making a copolymer comprising:
adding a solvent to a reactor;
adding a propylene and a catalyst mixture to the solvent in the reactor to make a first reaction mixture, wherein the catalyst mixture comprises: one or more catalysts, one or more cocatalysts, and one or more catalyst reactivators;
contacting ethylene with the first reaction mixture to make a second reaction mixture; and
contacting vinyl norbornene to the second reaction mixture to make a copolymer, wherein the copolymer has a weight-average molecular weight from about 2,500 g/mol to about 1,000,000 g/mol, wherein the copolymer has a propylene content of at least 50 wt. % wherein a vinyl norbornene content of the copolymer is at least 8.0 wt % of the copolymer, and wherein the copolymer has a viscosity from about 1,000 cP to about 2,500,000 cP at 100° C.
7. The method of claim 6 , wherein the one or more catalysts is a Ziegler-Natta catalyst.
8. The method of claim 6 , wherein the one or more catalysts is a metallocene complex.
9. The method of claim 6 , wherein the one or more catalysts is vanadium oxytrichloride, wherein the one or more cocatalysts is ethyl aluminum sesquichloride, and wherein the one or more catalyst reactivators is dichlorophenylacetic acid ethyl ester.
10. The method of claim 6 , wherein the one or more catalysts is bis(indenyl) zirconium dichloride, wherein the one or more cocatalysts comprises a first cocatalyst, a second cocatalyst, and a third cocatalyst, wherein the first cocatalyst is N,N-dimethylanilinium tetrakis(pentaflourophenyl) borate, wherein the second cocatalyst is methylaluminoxane, and the third cocatalyst is triisobutyl aluminum.
11. The method of claim 6 , wherein the copolymer has an ethylene:propylene ratio from about 40:60 to about 80:20.
12. The method of claim 6 , wherein adding propylene and the catalyst mixture to the solvent in the reactor to make a first reaction mixture has a propylene flow rate, wherein the propylene flow rate is about 1.0 gram/minute to about 100.0 grams/minute.
13. The method of claim 6 , wherein the solvent is hexane.
14. The method of claim 6 , wherein the copolymer has knumber-average molecular weight of less than 50,000 g/mol.
15. The method of claim 6 , wherein the copolymer has a viscosity from about 1,000 cP to about 250,000 cP at 100° C.
16. The method of claim 6 , wherein the copolymer has an ethylene content from about 5 wt. % to about 48 wt. %.