Polyethylene and polypropylene block copolymers

Patent metadata

Field	Value
Publication number	US-11279780-B2
Application number	US-201716303004-A
Country	US
Kind code	B2
Filing date	May 26, 2017
Priority date	May 27, 2016
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

A semicrystalline multiblock copolymer includes alternating blocks of semicrystalline isotactic polypropylene (iPP) and semicrystalline polyethylene (PE), having a block arrangement according to formula (I):(iPPw)p(PEx)(iPPy)m(PEz)n   (I),wherein p is 0 or 1; m is 0 or 1; n is 0 or 1; the sum of p, m, and n is 1, 2, or 3; and the sum of w, x, y, and z is greater than or equal to 40 kg/mol, with the provisos that: when m and n are 0, the sum of w and x is greater than or equal to 140 kg/mol; and when p and n are 0, the sum of y and x is greater than or equal to 140 kg/mol. Related compositions and methods are also provided.

First claim

The invention claimed is:

1. A semicrystalline multiblock copolymer comprising alternating blocks of semicrystalline isotactic polypropylene (iPP) and semicrystalline polyethylene (PE), having a block arrangement according to formula (I):
(iPP w ) p (PE x )(iPP y ) m (PE z ) n    (I),

wherein
block (PE x ) consists of formula

block (PE z ) consists of formula

p is 0 or 1;
m is 0 or 1;
n is 0 or 1;
the sum of p, m, and n is 1, 2, or 3; and
the sum of w, x, y, and z is greater than or equal to 40 kg/mol, with the provisos that:
when m and n are 0, the sum of w and x is greater than or equal to 140 kg/mol; and
when p and n are 0, the sum of y and x is greater than or equal to 140 kg/mol.

2. The semicrystalline multiblock copolymer according to claim 1 , wherein the copolymer is a diblock copolymer having a block arrangement according to formula (Ia):
iPP w PE x    (Ia).

3. The semicrystalline multiblock copolymer according to claim 2 , wherein w is greater than 70 kg/mol, and x is greater than 70 kg/mol.

4. The semicrystalline multiblock copolymer according to claim 3 , wherein at least one of w and x is greater than 100 kg/mol.

5. The semicrystalline multiblock copolymer according to claim 1 , wherein the copolymer is a triblock copolymer having a block arrangement according to formula (Ib) or formula (Ic):
iPP w PE x iPP y    (Ib)

PE x iPP y PE z    (Ic).

6. The semicrystalline multiblock copolymer according to claim 5 , wherein for formula (Ib), the sum of w, x, and y is greater than or equal to 70 kg/mol, and for formula (Ic), the sum of x, y, and z is greater than or equal to 70 kg/mol.

7. A semicrystalline multiblock copolymer comprising alternating blocks of semicrystalline isotactic polypropylene (iPP) and semicrystalline polyethylene (PE), wherein the copolymer is a tetrablock copolymer having a block arrangement according to formula (Id):
iPP w PE x iPP y PE z ,   (Id),

wherein
the sum of w, x, y, and z is greater than or equal to 40 kg/mol.

8. The semicrystalline multiblock copolymer according to claim 7 , wherein w, x, y, and z are each independently greater than or equal to 15 kg/mol.

9. The semicrystalline multiblock copolymer according to claim 7 , wherein the sum of w, x, y, and z is greater than or equal to 100 kg/mol.

10. A semicrystalline multiblock copolymer comprising alternating blocks of semicrystalline isotactic polypropylene (iPP) and semicrystalline polyethylene (PE), having a block arrangement according to formula (I):
(iPP w ) p (PE x )(iPP y ) m (PE z ) n    (I),

wherein
p is 0 or 1;
m is 0 or 1;
n is 0 or 1;
the sum of p, m, and n is 1, 2, or 3; and
the sum of w, x, y, and z is greater than or equal to 40 kg/mol, with the provisos that:
when m and n are 0, the sum of w and x is greater than or equal to 140 kg/mol; and
when p and n are 0, the sum of y and x is greater than or equal to 140 kg/mol, and

wherein said semicrystalline multiblock copolymer includes one or more blocks in addition to those of formula (I).

11. An adhesion layer comprising the semicrystalline multiblock copolymer according to claim 1 .

12. A multi-layer film or sheet comprising:
a first layer comprising polyethylene;
a second layer comprising polypropylene; and
an adhesion layer comprising the semicrystalline multiblock copolymer according to claim 1 ,
wherein the adhesion layer is disposed between the first layer and the second layer, and is in direct contact with the first layer and the second layer.

13. The multi-layer film or sheet according to claim 12 , wherein
the polyethylene in the first layer is selected from the group consisting of: high density polyethylene (HDPE), linear low-density polyethylene (LLDPE), ultra high molecular weight polyethylene (UHMWPE), low density polyethylene (LDPE), very low density polyethylene (VLDPE), and polyethylene polyolefin block copolymer; and
the polypropylene in the second layer is selected from the group consisting of: isotactic polypropylene (iPP), impact modified polypropylene, polypropylene fibers, and biaxially oriented polypropylene (BOPP).

14. A method of adhering a first layer comprising polyethylene and a second layer comprising polypropylene, the method comprising: contacting the first layer and the second layer with an adhesive composition comprising a semicrystalline multiblock copolymer according to claim 1 .

15. The method according to claim 14 , wherein the adhesive composition is provided in the form of a film or sheet and the adhesive composition is applied to the first layer or the second layer by:
blow molding;
electrospinning;
melt extruding;
injection molding;
application through sheer force; or
solvent casting.

16. A blended composition comprising polypropylene, polyethylene, and a semicrystalline multiblock copolymer according to claim 1 .

17. The composition according to claim 16 , comprising 0.2 to 5.0 wt % of the semicrystalline multiblock copolymer.

18. A process for forming the semicrystalline multiblock copolymer according to claim 1 , said process comprising:
in a reactor, in a non-polar, non-protic solvent, contacting propylene monomers with a catalyst, thereby forming an iPP block;
introducing ethylene monomers to the reactor, thereby forming a PE block covalently bonded to the iPP block, thus forming a semicrystalline diblock copolymer;
optionally, performing one or more additional steps of introducing to the reactor propylene and/or ethylene monomers, thus forming a semicrystalline multiblock copolymer having additional blocks.

19. The process according to claim 18 , wherein the catalyst is the reaction product of a pyridylamidohafnium catalyst precursor and an activator.

20. The process according to claim 19 , wherein the pyridylamidohafnium catalyst precursor is a compound of formula (II)

wherein
R 21 and R 21′ are independently selected from H and methyl;
R 22 and R 22′ are independently selected from isopropyl and tert-butyl;
R 23 is selected from H, isopropyl and tert-butyl; and
R 24 and R 24′ are independently selected from C 1 -C 4 linear or branched alkyl and benzyl.

21. The process according to claim 20 , wherein the activator is B(C 6 F 5 ) 3 and the pyridylamidohafnium catalyst precursor is:

22. The semicrystalline multiblock copolymer according to claim 1 , wherein the sum of p, m, and n is 2 or 3.

23. The semicrystalline multiblock copolymer according to claim 1 , wherein the semicrystalline multiblock copolymer:
comprises less than 1 wt % ethylene-co-propylene segments, based on the weight of the multiblock copolymer; and/or
has an NMR spectrum on which ethylene-co-propylene segments are not detectable.

Assignees

• Univ Cornell
• Univ Minnesota

Inventors

• Coates Geoffrey
• Eagan James
• Lapointe Anne
• Bates Frank S

Classifications

• C09J2423/106

  in the substrate · CPC title

• C09J2423/046

  in the substrate · CPC title

• C08L2207/10

  Peculiar tacticity · CPC title

• C08L2207/068

  Ultra high molecular weight polyethylene · CPC title

• C08L2207/066

  LDPE (radical process) · CPC title