Low emission propylene homopolymer with high melt flow

Patent metadata

Field	Value
Publication number	US-9751962-B2
Application number	US-201415030556-A
Country	US
Kind code	B2
Filing date	Nov 19, 2014
Priority date	Nov 22, 2013
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

Propylene homopolymer with reduced emission value and high melt flow rate.

First claim

The invention claimed is:

1. A propylene homopolymer having
(a) a melt flow rate MFR 2 (230° C./2.16 kg) measured according to ISO 1133 in the range of 75.0 to 500 g/10 min; and
(b) a pentad isotacticity (mmmm) of more than 90.0% determined by 13 C-NMR spectroscopy
wherein further
(c) the propylene homopolymer fulfills inequation (I)
VOC≦(MFR×0.08)+201.0

wherein
VOC is the amount of volatile organic compounds (VOC) [in ppm] measured according to VDA 278:2002 of the propylene homopolymer;
MFR is the melt flow rate MFR 2 (230° C./2.16 kg) measured according to ISO 1133 of the propylene homopolymer, and
(d) the propylene homopolymer has a melting temperature Tm of equal to or more than 160° C.

2. The propylene homopolymer according to claim 1 having an amount of volatile organic compounds (VOC) measured according to VDA 278:2002 of equal or below 210 ppm.

3. The propylene homopolymer according to claim 1 having a crystallization temperature of equal to or more than 114° C.

4. The propylene homopolymer according to claim 1 , having a xylene cold soluble content (XCS) determined according ISO 16152 (25° C.) of at least 1.8 wt.-%.

5. The propylene homopolymer according to claim 1 , having 2,1 erythro regio-defects of equal to or below 0.4 mol.-% determined by 13 C-NMR spectroscopy.

6. The propylene homopolymer according to claim 1 , having a pentad isotacticity (mmmm) of more than 93.0%.

7. The propylene homopolymer according to claim 1 , fulfilling inequation (II)
FOG≦(MFR×1.26)+350.0

wherein
FOG is the amount of fogging compounds (FOG) [in ppm] measured according to VDA 278:2002 of the propylene homopolymer; and
MFR is the melt flow rate MFR 2 (230° C./2.16 kg) measured according to ISO 1133 of the propylene homopolymer.

8. The propylene homopolymer according to claim 1 , having an amount of fogging compounds (FOG) measured according to VDA 278:2002 of not more than 580 ppm.

9. The propylene homopolymer according to claim 1 , having a tensile modulus measured at 23° C. according to ISO 527-1 (cross head speed 1 mm/min) of at least 1,500 MPa.

10. An article comprising the propylene homopolymer according claim 1 .

11. A process for producing a propylene homopolymer according to claim 1 , wherein propylene has been polymerized in the presence of
(a) a Ziegler-Natta catalyst (ZN-C) comprising compounds (TC) of a transition metal of Group 4 to 6 of IUPAC, a Group 2 metal compound (MC) and an internal donor (ID), wherein said internal donor (ID) is a non-phthalic compound selected from optionally substituted glutarates and citraconate;
(b) optionally a co-catalyst (Co),
(c) optionally an external donor (ED), and
(d) the molar-ratio of co-catalyst (Co) to external donor (ED) [Co/ED] is 5 to 45.

12. The process according to claim 11 , wherein the propylene homopolymer is produced in a sequential polymerization process comprising at least two reactors (R1) and (R2), in the first reactor (R1) a first propylene homopolymer fraction (H-PP1) is produced and subsequently transferred into the second reactor (R2), in the second reactor (R2) a second propylene homopolymer fraction (H-PP2) is produced in the presence of the first propylene homopolymer fraction (H-PP1).

13. The propylene homopolymer according to claim 2 , having a crystallization temperature of equal to or more than 114° C.

14. The propylene homopolymer according to claim 2 , having a xylene cold soluble content (XCS) determined according ISO 16152 (25° C.) of at least 1.8 wt.-%.

15. The propylene homopolymer according to claim 2 , having 2,1 erythro regio-defects of equal to or below 0.4 mol.-% determined by 13 C-NMR spectroscopy.

16. The propylene homopolymer according to claim 2 , having a pentad isotacticity (mmmm) of more than 93.0%.

17. The propylene homopolymer according to claim 2 , fulfilling inequation (II)
FOG≦(MFR×1.26)+350.0

wherein
FOG is the amount of fogging compounds (FOG) [in ppm] measured according to VDA 278:2002 of the propylene homopolymer; and
MFR is the melt flow rate MFR 2 (230° C./2.16 kg) measured according to ISO 1133 of the propylene homopolymer.

Assignees

• Borealis Ag

Inventors

• Wang Jingbo
• Lilja Johanna
• Horill Thomas
• Gahleitner Markus
• Denifl Peter
• Leinonen Timo

Classifications

• C08F110/06 Primary

  Propene · CPC title

• C08F2500/12

  Melt flow index or melt flow ratio · CPC title

• C08F2500/15

  Isotactic · CPC title

• C08F4/16

  of silicon, germanium, tin, lead, titanium, zirconium or hafnium · CPC title

• C08F2/44

  Polymerisation in the presence of compounding ingredients, e.g. plasticisers, dyestuffs, fillers · CPC title