Article comprising a fiber reinforced polypropylene composition
The present invention is directed to an article comprising a fiber reinforced composition (C), said composition comprising a propylene polymer (PP), an elastomeric ethylene copolymer (E) and fibers (F).
1. An article comprising a fiber reinforced composition (C), comprising
(i) 33.0 to 76.0 wt.-% of a propylene homopolymer (PP) which is at least bimodal, has a xylene cold soluble (XCS) content below 3.1 wt %, and has a melt flow rate MFR 2 (230° C., 2.16 kg) determined according to ISO 1133 in the range of 30 to 250 g/10 min,
(ii) 2.5 to 10.0 wt.-% of an elastomeric ethylene copolymer (E) which is a copolymer of ethylene and a C 4 -C 10 α-olefin, having a melt flow rate MFR 2 (190° C., 2.16 kg) determined according to ISO 1133 of at least 25.0 g/10 min,
(iii) 1.5 to 2.0 wt.-% of an adhesion promoter (AP), and
(iv) 20.0 to 50.0 wt.-% of fibers (F)
based on the overall weight of the fiber reinforced composition (C), and
the fiber reinforced composition (C) not containing more than 5 wt.-%, based on the total amount the fiber reinforced composition (C), of polymers other than the propylene homopolymer (PP), the elastomeric ethylene copolymer (E), and the adhesion promoter (AP).
2. The article according to claim 1 , wherein the fiber reinforced composition (C) has a melt flow rate MFR 2 (230° C., 2.16 kg) determined according to ISO 1133 below 100.0 g/10 min.
3. The article according to claim 1 , wherein the adhesion promoter (AP) is a polar modified polypropylene (PM-PP) which is a propylene homo- or copolymer grafted with maleic anhydride having a melt flow rate MFR (190° C., 2.16 kg) determined according to ISO 1133 of at least 50.0 g/10 min.
4. The article according to claim 1 , wherein the fiber reinforced composition (C) comprises the fibers (F) and the ethylene copolymer (E) in a weight ratio of 95:5 to 70:30.
5. The article according to claim 1 , wherein the elastomeric ethylene copolymer (E) has
a) a content of C 4 -C 10 α-olefin of 2.0 to 25.0 mol-%, and/or
b) a density below 0.900 g/cm 3 .
6. The article to claim 1 , wherein the elastomeric ethylene copolymer (E) is a copolymer of ethylene and 1-octene.
7. The article according to claim 1 , wherein the fibers (F) are selected from the group consisting of glass fibers, metal fibers, ceramic fibers, carbon fibers, and graphite fibers.
8. The article according to claim 1 , wherein the fibers (F) are short fibers (SF) and/or long fibers (LF), wherein the short fibers have an average length in the range of 2.0 to 8.0 mm, and the long fibers have a length of 8.0 to 25.0 mm.
9. The article according to claim 8 , wherein the short fibers are short glass fibers (SGF) and/or the long fibers are long glass fibers (LGF).
10. The article according to claim 1 , comprising at least 80.0 wt.-% of the fiber reinforced composition (C), based on the overall weight of the article.
11. The article according to claim 1 , wherein said article is a moulded article.
12. The article according to claim 11 , wherein said moulded article is an injection moulded article.