Propylene copolymer for blow molded articles

Patent metadata

Field	Value
Publication number	US-9969821-B2
Application number	US-201214366343-A
Country	US
Kind code	B2
Filing date	Dec 18, 2012
Priority date	Dec 23, 2011
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

Propylene copolymer having a melt flow rate MFR 2 (230° C.) in the range of more than 0.5 to below 2.5 g/10 min, a xylene cold soluble content (XCS) in the range of 30.0 to 40.0 wt-%, a comonomer content in the range of more than 7.5 to 12.0 wt.-%, wherein further the comonomer content of xylene cold soluble (XCS) fraction of the propylene copolymer is in the range of 16.0 to 28.0 wt.-%.

First claim

The invention claimed is:

1. A Ziegler-Natta catalyzed propylene copolymer having:
(a) a melt flow rate MFR 2 at 230° C. measured according to ISO 1133 in the range of more than 0.5 to below 2.5 g/10 min,
(b) a xylene cold soluble content (XCS) determined according ISO 16152 at 25° C. in the range of 30.0 to 40.0 wt. %,
(c) a comonomer content in the range of more than 7.5 to 12.0 wt. %,
wherein further;
the comonomer content of xylene cold soluble (XCS) fraction of the propylene copolymer is in the range of 16.0 to 28.0 wt. %.

2. The propylene copolymer according to claim 1 , wherein the propylene copolymer fulfills inequation (I):

Co
⁡

(
total
)

Co
⁡

(
XCS
)

≤
0.7

wherein;
Co (total) is the comonomer content [wt. %] of the propylene copolymer, and
Co (XCS) is the comonomer content [wt. %] of the xylene cold soluble fraction (XCS) of the propylene copolymer.

3. The propylene copolymer according to claim 1 , wherein the propylene copolymer has a melting temperature Tm determined by differential scanning calorimetry (DSC) in the range of 145 to 159° C.

4. The propylene copolymer according to claim 1 , wherein the propylene copolymer has an intrinsic viscosity (IV) of the xylene cold soluble (XCS) fraction determined according to DIN ISO 1628/1 in Decalin at 135° C. in the range of more than 1.8 to below 3.5 dl/g.

5. The propylene copolymer according to claim 1 , wherein the propylene copolymer has a flexural modulus measured according to ISO 178 of not more than 600 MPa.

6. The propylene copolymer according to claim 1 , wherein the propylene copolymer is a heterophasic propylene copolymer comprising a matrix (M) and an elastomeric propylene copolymer (E) dispersed in said matrix (M), wherein said matrix (M) is a random propylene copolymer (R-PP).

7. The propylene copolymer according to claim 6 , wherein the weight ratio between the matrix (M) and the elastomeric propylene copolymer (E) is 50/50 to 80/20.

8. The propylene copolymer according to claim 6 , wherein the comonomer content of the random propylene copolymer (R-PP) is in the range of 1.0 to 9.0 wt. %.

9. The propylene copolymer according to claim 6 , wherein the propylene copolymer fulfills inequation (II):

Co
⁡

(
total
)

Co
⁡

(
RPP
)

≥
1.1

wherein;
Co (total) is the comonomer content [wt. %] of the propylene copolymer, and
Co (RPP) is the comonomer content [wt. %] of the random propylene copolymer (R-PP).

10. The propylene copolymer according to claim 6 , wherein the random propylene copolymer (R-PP) has a xylene cold soluble (XCS) fraction in the range of 2.0 to 15.0 wt. %.

11. The propylene copolymer according to claim 6 , wherein the random propylene copolymer (R-PP) comprises at least two different fractions, a first random propylene copolymer fraction (R-PP1) and a second random propylene copolymer fraction (R-PP2).

12. The propylene copolymer according to claim 11 , wherein:
(a) the weight ratio between the first random propylene copolymer fraction (R-PP1) and the second random propylene copolymer fraction (R-PP2) is 20/80 to 80/20, and/or
(b) the first random propylene copolymer fraction (R-PP1) has a comonomer content in the range 0.5 to 5.0 wt. %, and/or
(c) the second random propylene copolymer fraction (R-PP2) has a commoner content in the range 0.5 to 15.0 wt. %.

13. The propylene copolymer according to claim 6 , wherein the elastomeric propylene copolymer (E) has a comonomer content in the range of 16.0 to 26.0 wt. %.

14. A blow molded article comprising the propylene copolymer according to claim 1 .

15. The blow molded article according to claim 14 , wherein the article is a bottle.

Assignees

• Borealis Ag

Inventors

• Klimke Katja
• Bernreitner Klaus
• Sandholzer Martina
• Gahleitner Markus

Classifications

• C08L23/14

  Copolymers of propene (C08L23/16 takes precedence) · CPC title

• Y10T428/1397

  Single layer [continuous layer] · CPC title

• C08F10/06 Primary

  Propene · CPC title

• C08F210/06 Primary

  Propene · CPC title

• C08L23/08

  Copolymers of ethene (C08L23/16 takes precedence) · CPC title