Multiple reactor and multiple zone polyolefin polymerization
AssigneeChevron Phillips Chemical Company LP
InventorsJoseph A. Curren, Rebecca A. Gonzales, Scott E. Kufeld, Joel A. Mutchler, Eric J. Netemeyer, Jamie N. Sutherland, Paul J. DesLauriers, Jeffrey S. Fodor
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Abstract
Apparatuses and processes that produce multimodal polyolefins, and in particular, polyethylene resins, are disclosed herein. This is accomplished by using two reactors in series, where one of the reactors is a multi-zone circulating reactor that can circulate polyolefin particles through two polymerization zones optionally having two different flow regimes so that the final multimodal polyolefin has improved product properties and improved product homogeneity.
Claims36
A trimodal polyethylene resin having a low molecular weight (LMW) component, an intermediate molecular weight (IMW) component, and a high molecular weight (HMW) component;
- wherein the LMW component is present in an amount of from about 20 wt. % to about 75 wt. %;
- wherein the IMW component is present in an amount of from about 5 wt. % to about 40 wt. %;
- wherein the LMW component has a weight average molecular weight of from about 20 kg/mol to about 150 kg/mol;
- wherein the IMW component has a weight average molecular weight of from about 85 kg/mol to about 350 kg/mol;
- wherein the weight average molecular weight of the IMW component is greater than the weight average molecular weight of the LMW component;
- wherein the weight average molecular weight of the HMW component is greater than the weight average molecular weight of the IMW component;
- and wherein the trimodal polyethylene resin has a strain hardening modulus of from about 50 MPa to about 90 MPa, when tested in accordance with ISO 18488-2015 (E),
- wherein (A1) the HMW component is present in an amount of from about 10 wt. % to about 60 wt. %;
- (A2) the HMW component has weight average molecular weight of greater than about 350 kg/mol;
- or (A3) both the HMW component is present in an amount of from about 10 wt. % to about 60 wt. %, and the HMW component has weight average molecular weight of greater than about 350 kg/mol;
- wherein the trimodal polyethylene resin is characterized by (B1) a short chain branching content in the LMW component of from about 0 to about 5 short chain branches per 1,000 carbon atoms;
- (B2) a short chain branching content in the IMW component of from about 0.1 to about 10 short chain branches per 1,000 carbon atoms;
- (B3) a short chain branching content in the HMW component of from about 1 to about 15 short chain branches per 1,000 carbon atoms;
- or (B4) any combination of (B1)-(B3);
- wherein the trimodal polyethylene resin has a density of from greater than about 0.940 g/cc to about 0.960 g/cc, when tested in accordance with ASTM D1505;
- wherein the trimodal polyethylene resin has (C1) a tensile natural draw ratio at room temperature of from about 300% to about 600%, when tested in accordance with ASTM D638;
- (C2) a tensile natural draw ratio at 80° of less than about 400% when tested in accordance with ASTM D638;
- or (C3) both a tensile natural draw ratio at room temperature of from about 300% to about 600%, and a tensile natural draw ratio at 80° C. of less than about 400%, when tested in accordance with ASTM D638;
- and
- wherein the trimodal polyethylene resin has (D1) a long chain branching content of less than about 0.01 long chain branches per 1,000 carbon atoms;
- (D2) an η0 (eta_0) of equal to or greater than about 0.7×105 Pa-s;
- (D3) an η251 (eta_251) of less than about 1.5×103 Pa-s;
- or (D4) any combination of (D1)-(D3).
The trimodal polyethylene resin of claim/having a resistance to slow crack growth of equal to or greater than about 800 h, when tested in accordance with ASTM F1473, wherein the resistance to slow crack growth is defined as the polyethylene notch tensile test (PENT) failure time.
The trimodal polyethylene resin of claim having a resistance to slow crack growth of equal to or greater than about 8,760 h, when tested in accordance with ISO 16770 at 80° C. and 6 MPa, wherein the resistance to slow crack growth is defined as the full notch creep test (FNCT) failure time.
Dependencies are inferred from the claim text.