US 11,931,973 B2
Weatherable fiber-reinforced propylene composition
Aaron H. Johnson, Winona, MN (US); and Darin Grinsteinner, Fort Mitchell, KY (US)
Assigned to Ticona LLC, Florence, KY (US)
Filed by Ticona LLC, Florence, KY (US)
Filed on Feb. 19, 2019, as Appl. No. 16/279,035.
Claims priority of provisional application 62/637,675, filed on Mar. 2, 2018.
Prior Publication US 2019/0270260 A1, Sep. 5, 2019
Int. Cl. B29C 70/20 (2006.01); B29C 70/44 (2006.01); B29K 23/00 (2006.01); B29K 309/08 (2006.01); C08K 5/00 (2006.01); C08K 5/105 (2006.01); C08K 5/3492 (2006.01); C08K 5/38 (2006.01); C08K 5/527 (2006.01); C08K 7/14 (2006.01); C08L 23/12 (2006.01); C08L 23/14 (2006.01)
CPC B29C 70/20 (2013.01) [B29C 70/443 (2013.01); C08K 5/005 (2013.01); C08K 5/105 (2013.01); C08K 5/34924 (2013.01); C08K 5/38 (2013.01); C08K 5/527 (2013.01); C08K 7/14 (2013.01); C08L 23/12 (2013.01); C08L 23/14 (2013.01); B29K 2023/12 (2013.01); B29K 2023/14 (2013.01); B29K 2309/08 (2013.01)] 24 Claims
 
1. A fiber-reinforced polymer composition comprising:
a polymer matrix that contains a propylene polymer, wherein the polymer matrix constitutes from about 20 wt. % to about 90 wt. % of the composition;
a plurality of long reinforcing fibers that are distributed within the polymer matrix, wherein the fibers constitute from about 10 wt. % to 50 wt. % of the composition; and
a stabilizer system consisting of a sterically hindered phenol antioxidant, phosphite antioxidant, thioester antioxidant, and optionally a UV stabilizer, wherein the weight ratio of the thioester antioxidant to the phosphite antioxidant is from about 1:1 to about 5:1 and the weight ratio of the phosphite antioxidant to the sterically hindered phenol antioxidant is from about 1.5:1 to about 5:1,
wherein the polymer composition exhibits a tensile strength from 140.6 MPa to about 300 MPa as determined according to ISO Test No. 527-1:2012 at 23° C., wherein the phosphite antioxidant is an aryl diphosphite having the following general structure (IX):

OG Complex Work Unit Chemistry
wherein,
R1, R2, R3, R4, R5, R6, R7, R8, R9, and R10 are independently selected from hydrogen, C1 to C10 alkyl, and C3 to C30 branched alkyl.