US 12,325,764 B2
Propylene polymer resins
Kimberly Miller McLoughlin, Pittsburgh, PA (US); Rodney Peratt, Pittsburgh, PA (US); Craig Meverden, Pittsburgh, PA (US); and Michael Stephans, Pittsburgh, PA (US)
Assigned to Braskem America, Inc., Philadelphia, PA (US)
Filed by Braskem America, Inc., Philadelphia, PA (US)
Filed on Jun. 8, 2023, as Appl. No. 18/207,416.
Application 18/207,416 is a division of application No. 14/773,131, abandoned, previously published as PCT/US2014/027625, filed on Mar. 14, 2014.
Claims priority of provisional application 61/791,986, filed on Mar. 15, 2013.
Prior Publication US 2023/0312783 A1, Oct. 5, 2023
Int. Cl. C08F 110/06 (2006.01); B29C 51/02 (2006.01); B29K 23/00 (2006.01); C08F 2/01 (2006.01); C08F 10/06 (2006.01); C08J 5/18 (2006.01)
CPC C08F 110/06 (2013.01) [C08F 2/01 (2013.01); C08F 10/06 (2013.01); C08J 5/18 (2013.01); B29C 51/02 (2013.01); B29K 2023/10 (2013.01); C08J 2327/12 (2013.01)] 23 Claims
 
1. A method of making a thermoformed article, comprising:
extruding a sheet comprising a propylene homopolymer resin having:
a. a melt flow rate greater than 0.4 grams per 10 minutes, measured according to ASTM D1238 (230° C., 2.16 kg);
b. a Mw/Mn greater than 5.5, a Mz/Mn greater than 20, and a Mz/Mw greater than or equal to 4.0;
c. a critical frequency for onset of shear-thinning, 1/K, less than 1.2 s−1, where K is a Cross model constant;
d. a melt strength greater than 15 cN at 190° C.;
e. a xylene soluble content greater than or equal to 2%, measured according to ASTM D5492;
f. a mesopentad content in the xylene-insoluble fraction greater than 96.0%; and
g. a temperature suitable for forming of at least 290° C., to form an extruded sheet, and
thermoforming the extruded sheet into the shape of an article to form a thermoformed article.