US 12,031,001 B2
Structured dense fluoropolymer films and methods of making same
Michael E. Kennedy, Oxford, PA (US); and Shaofeng Ran, Kennett Square, PA (US)
Assigned to W. L. Gore & Associates, Inc., Newark, DE (US)
Appl. No. 17/277,776
Filed by W. L. Gore & Associates, Inc., Newark, DE (US)
PCT Filed Oct. 5, 2018, PCT No. PCT/US2018/054559
§ 371(c)(1), (2) Date Mar. 19, 2021,
PCT Pub. No. WO2020/072072, PCT Pub. Date Apr. 9, 2020.
Prior Publication US 2021/0347955 A1, Nov. 11, 2021
Int. Cl. C08J 5/18 (2006.01); B32B 3/28 (2006.01); B32B 27/08 (2006.01); B32B 27/32 (2006.01); B32B 37/18 (2006.01); B32B 38/00 (2006.01); C08L 27/18 (2006.01)
CPC C08J 5/18 (2013.01) [B32B 3/28 (2013.01); B32B 27/08 (2013.01); B32B 27/322 (2013.01); B32B 37/182 (2013.01); B32B 38/0012 (2013.01); C08L 27/18 (2013.01); B32B 2307/518 (2013.01); B32B 2307/7246 (2013.01); C08J 2327/18 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A structured fluoropolymer film comprising:
a dense fluoropolymer film including a plurality of structures having a height at least two times a thickness of a corresponding unstructured fluoropolymer film, wherein the thickness of the corresponding unstructured fluoropolymer film is from about 1 μm to about 50 μm, and wherein the height of the plurality of structures is from 2 μm to 500 μm; and
at least a 20% increase in a displacement induction period when compared to the corresponding unstructured dense fluoropolymer film when measured in a biaxial tensile curve at a temperature of about 125° C.,
wherein the dense fluoropolymer film has a water vapor permeability coefficient of 0.015 g-mm/m2/day or less, and a matrix tensile strength of at least 69 MPa in both the x and y directions,
wherein the dense fluoropolymer film has a thickness from 0.5 microns to 250 microns,
wherein the structured fluoropolymer film has at least a 5% increase in mass per unit area when compared to the corresponding unstructured fluoropolymer film, and
wherein the structured fluoropolymer film has a methane permeability of less than 500 μg*μm/cm2/min.