Biaxially oriented pipe

Patent metadata

Field	Value
Publication number	US-12083732-B2
Application number	US-202017764788-A
Country	US
Kind code	B2
Filing date	Oct 2, 2020
Priority date	Oct 4, 2019
Publication date	Sep 10, 2024
Grant date	Sep 10, 2024

Abstract

The invention relates to a biaxially oriented pipe made of a polymer composition comprising a propylene-based polymer, wherein the propylene-based polymer comprises A) a heterophasic propylene copolymer, wherein the heterophasic propylene copolymer consists of (a1) a propylene-based matrix, wherein the propylene-based matrix consists of a propylene homopolymer and/or a propylene copolymer consisting of at least 70 wt % of propylene monomer units and at most 30 wt % of ethylene and/or α-olefin monomer units, based on the total weight of the propylene-based matrix and (a2) a dispersed ethylene-α-olefin copolymer, wherein the sum of the total amount of propylene-based matrix and total amount of the dispersed ethylene-α-olefin copolymer in the heterophasic propylene copolymer is 100 wt %, wherein the amount of (a2) with respect to the propylene-based polymer is 2.0 to 30.0 wt %.

First claim

The invention claimed is:

1. A biaxially oriented pipe made of a polymer composition comprising a propylene-based polymer, wherein the propylene-based polymer comprises
A) a heterophasic propylene copolymer, wherein the heterophasic propylene copolymer consists of
(a1) a propylene-based matrix,
wherein the propylene-based matrix consists of a propylene homopolymer and/or a propylene copolymer consisting of at least 70 wt % of propylene monomer units and at most 30 wt % of ethylene and/or α-olefin monomer units, based on the total weight of the propylene-based matrix and
(a2) a dispersed ethylene-α-olefin copolymer,
wherein the sum of the total amount of propylene-based matrix and total amount of the dispersed ethylene-α-olefin copolymer in the heterophasic propylene copolymer is 100 wt %,
wherein the amount of (a2) with respect to the propylene-based polymer is 2.0 to 30.0 wt %.

2. The pipe according to claim 1 , wherein the amount of (a2) with respect to the propylene-based polymer is at least 3.0 wt %.

3. The pipe according to claim 1 , wherein the amount of (a2) with respect to A) is 2.0 to 40 wt %.

4. The pipe according to claim 1 , wherein the amount of ethylene monomer units in (a2) is 34 to 60 wt %.

5. The pipe according to claim 1 , wherein (a1) is the propylene homopolymer and (a2) is ethylene-propylene copolymer.

6. The pipe according to claim 1 , wherein the propylene-based polymer has a Melt Flow Index of 0.1 to 10.0 g/10 min measured according to ISO1133-1:2011 (230° C./2.16 kg).

7. The pipe according to claim 1 , wherein the amount of the propylene-based polymer with respect to the total amount of polymers in the polymer composition is at least 95 wt %.

8. The pipe according to claim 1 , wherein the polymer composition further comprises 0 to 5 wt % of additives and 0 to 40 wt % of fillers.

9. The pipe according to claim 1 , wherein the pipe is made by a process comprising the steps of:
a) forming a polymer composition into a tube, and
b) stretching the tube of step a) in the axial direction and in the peripheral direction to obtain the biaxially oriented pipe,
wherein step b) is performed at a drawing temperature of 140 to 160° C. and at an axial draw ratio of 1.1 to 5.0 and an average hoop draw ratio of 1.1 to 3.0.

10. The pipe according to claim 1 , wherein the pipe has a time to failure of at least 100 hours according to ISO 1167-1 determined at a stress level of 20 MPa and a temperature of 20° C.

11. The pipe according to claim 1 , wherein the amount of A) with respect to the propylene-based polymer is 30 to 100 wt %.

12. The pipe according to claim 1 , wherein the propylene-based polymer consists of A), wherein the amount of (a2) with respect to A) is 2.0 to 30 wt %.

13. A biaxially oriented pipe made of a polymer composition comprising a propylene-based polymer, wherein the propylene-based polymer comprises
A) a heterophasic propylene copolymer, wherein the heterophasic propylene copolymer consists of
(a1) a propylene-based matrix,
wherein the propylene-based matrix consists of a propylene homopolymer and/or a propylene copolymer consisting of at least 70 wt % of propylene monomer units and at most 30 wt % of ethylene and/or α-olefin monomer units, based on the total weight of the propylene-based matrix and
(a2) a dispersed ethylene-α-olefin copolymer,
wherein the sum of the total amount of propylene-based matrix and total amount of the dispersed ethylene-α-olefin copolymer in the heterophasic propylene copolymer is 100 wt %,
wherein the amount of (a2) with respect to the propylene-based polymer is 2.0 to 30.0 wt %

B) a propylene homopolymer and/or
C) a random copolymer of propylene and a comonomer which is ethylene and/or an α-olefin having 4 to 10 carbon atoms.

14. The pipe according to claim 13 , wherein the amount of B) with respect to the propylene-based polymer is 5.0 to 70 wt %.

15. The pipe according to claim 13 , wherein the amount of C) with respect to the propylene-based polymer is 1.0 to 20 wt %.

Assignees

• Sabic Global Technologies Bv

Inventors

• Taraiya Ajay Kumar
• Soliman Maria
• Degenhart Peter

Classifications

• F16L9/12

  of plastics with or without reinforcement (F16L9/16 - F16L9/22 take precedence) · CPC title

• B29K2023/16

  EPM, i.e. ethylene-propylene copolymers; EPDM, i.e. ethylene-propylene-diene copolymers; EPT, i.e. ethylene-propylene terpolymers · CPC title

• B29K2023/12

  PP, i.e. polypropylene · CPC title

• B29K2023/08

  Copolymers of ethylene (B29K2023/16 takes precedence) · CPC title

• B29C55/005 Primary

  characterised by the choice of materials · CPC title