US 11,702,521 B2
Polymer blends and articles made therefrom
Zhenyu Zhu, Shanghai (CN); and Jianya Cheng, Kingwood, TX (US)
Assigned to ExxonMobil Chemical Patents Inc., Baytown, TX (US)
Filed by ExxonMobil Chemical Patents Inc., Baytown, TX (US)
Filed on Nov. 18, 2021, as Appl. No. 17/455,579.
Application 17/455,579 is a continuation of application No. 14/423,042, granted, now 11,214,659, previously published as PCT/US2013/062589, filed on Sep. 30, 2013.
Claims priority of provisional application 61/718,861, filed on Oct. 26, 2012.
Prior Publication US 2022/0153940 A1, May 19, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. C08L 23/08 (2006.01); C08J 5/18 (2006.01)
CPC C08J 5/18 (2013.01) [C08L 23/0815 (2013.01); C08J 2323/06 (2013.01); C08J 2323/08 (2013.01); C08J 2423/06 (2013.01); C08J 2423/08 (2013.01); C08L 2203/16 (2013.01); C08L 2205/025 (2013.01); C08L 2207/07 (2013.01)] 16 Claims
 
1. A polymer composition comprising:
(A) 10 wt. % to 50 wt. % of a Ziegler-Natta-catalyzed LLDPE polymer that is heterogeneously branched, has polymer units derived from ethylene and at least one of butene-1 and hexene-1, and has (i) density from 0.917 to 0.926 g/cm3, (ii) melt index from 0.7 g/10 min to 2.0 g/10 min, and (iii) a CDBI of less than 50.0%; and
(B) 90 wt. % to 50 wt. % of a metallocene-catalyzed LLDPE polymer having:
i. a melt index of from about 0.5 g/10 min to about 1.0 g/10 min,
ii. a melt index ratio of from about 20 to about 40,
iii. a weight average molecular weight (Mw) of from about 20,000 to about 200,000 g/mol,
iv. a molecular weight distribution (Mw/Mn) of from about 2.0 to about 4.5;
v. a density of from 0.915 to 0.921 g/cm3,
vi. a first peak and a second peak in a comonomer distribution analysis, wherein the first peak has a maximum at a log(Mw) value of 4.3 to 4.7 and a TREF elution temperature of 85.0° C. to 91.0° C. and the second peak has a maximum at a log(Mw) value of 5.1 to 5.4 and a TREF elution temperature of 60.0° C. to 65.0° C., and
vii. a CDBI of less than 35.0%,
wherein:
a film of the polymer composition has an MD Elmendorf Tear value greater than an expected MD Elmendorf Tear value determined from a blend rule for a film made from a blend comprising the Ziegler-Natta-catalyzed LLDPE and the metallocene-catalyzed LLDPE,
where the blend rule is defined as:

OG Complex Work Unit Math
wherein MDTearx is the MD Elmendorf Tear value for a film having x wt % of the Ziegler-Natta-catalyzed LLDPE; wt. %xZN1 is the weight percent of the Ziegler-Natta-catalyzed LLDPE in the blend; and further provided that wt % of the Ziegler-Natta-catalyzed LLDPE and wt % of the metallocene-catalyzed LLDPE add to 100 wt %.