Adhesive compositions of propylene-based and ethylene-based polymers

Patent metadata

Field	Value
Publication number	US-9803113-B2
Application number	US-201314406917-A
Country	US
Kind code	B2
Filing date	Aug 21, 2013
Priority date	Sep 19, 2012
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

The present invention is related to adhesive compositions and their applications. In particular, the adhesive compositions described herein comprise a propylene-based polymer and an ethylene-based polymer with varying comonomer content.

First claim

What is claimed is:

1. An adhesive composition comprising:
(a) at least one propylene-based polymer comprising more than 50 wt % of propylene-derived units and at least one first comonomer-derived units, said propylene-based polymer having a Brookfield viscosity of at least 250 mPa·sec measured by ASTM D-3236 at 190° C., a heat of fusion of at least 60 J/g measured by differential scanning calorimetry and a characteristic time (t c ) in the range from 1 to 1000 nanoseconds;
(b) an ethylene-based polymer comprising more than 50 wt % ethylene-derived units and at least one second comonomer-derived units, said ethylene-based polymer having a Brookfield viscosity of at least 250 mPa·sec measured by ASTM D-3236 at 190° C., a heat of fusion in the range from 1 to 100 J/g measured by differential scanning calorimetry and a characteristic time (t c ) in the range from 1 to 1500 nanoseconds;
wherein said at least one first comonomer and said at least one second comonomer are the same or different;
wherein said characteristic time (t c ) in units of nanoseconds is defined by Equation 1:

t
c

=

BV

Density
×
Heat
⁢

⁢
of
⁢

⁢
Fusion

(

Equation
⁢

⁢
1

)

wherein said BV is the Brookfield viscosity of said propylene-based polymer or said ethylene-based polymer measured by ASTM D-3236 at 190° C. in units of mPa·sec, said Density is the density of said propylene-based polymer or said ethylene-based polymer in units of g/cm 3 at 23° C., and said Heat of Fusion is the heat of fusion of said propylene-based polymer or said ethylene-based polymer in units of J/g.

2. The adhesive composition of claim 1 , wherein said at least one first comonomer is selected from the group consisting of ethylene and a C 4 to C 20 alpha-olefin.

3. The adhesive composition of claim 1 , wherein said at least one first comonomer comprises ethylene.

4. The adhesive composition of claim 1 , wherein said propylene-based polymer comprises 90 wt % to 99 wt % of propylene-derived units and 10 wt % to 1 wt % of ethylene-derived units, based on the weight of said propylene-based polymer.

5. The adhesive composition of claim 1 , wherein said Brookfield viscosity measured by ASTM D-3236 at 190° C. of said propylene-based polymer is from 250 to 25,000 mPa·sec.

6. The adhesive composition of claim 1 , wherein said heat of fusion measured by differential scanning calorimetry of said propylene-based polymer is from 60 to 150 J/g.

7. The adhesive composition of claim 1 , wherein said characteristic time (t c ) of said propylene-based polymer is from 1 to 800 nanoseconds.

8. The adhesive composition of claim 1 , wherein said propylene-based polymer has a ratio of a weight-average molecular weight (M w ) to a number-average molecular weight (M n ) in the range from 2 to 10.

9. The adhesive composition of claim 1 , wherein said at least one second comonomer is a C 3 to C 20 alpha-olefin.

10. The adhesive composition of claim 1 , wherein said at least one second comonomer comprises octene.

11. The adhesive composition of claim 1 , wherein said ethylene-based polymer comprises 51 wt % to 99 wt % of ethylene-derived units and 49 wt % to 1 wt % of octene-derived units, based on the weight of the said ethylene-based polymer.

12. The adhesive composition of claim 1 , wherein said Brookfield viscosity measured by ASTM D-3236 at 190° C. of said ethylene-based polymer is from 250 to 50,000 mPa·sec.

13. The adhesive composition of claim 1 , wherein said heat of fusion measured by differential scanning calorimetry of said ethylene-based polymer is from 1 to 60 J/g.

14. The adhesive composition of claim 1 , wherein said characteristic time (t c ) of said ethylene-based polymer is from 1 to 1200 nanoseconds.

15. The adhesive composition of claim 1 , wherein said ethylene-based polymer has a ratio of a weight-average molecular weight (M w ) to a number-average molecular weight (M n ) in the range from 1 to 10.

16. The adhesive composition of claim 1 , wherein said first comonomer and said second comonomer are different, said first comonomer is ethylene, and said second comonomer is octene.

17. The adhesive composition of claim 1 , further comprising one or more additives, said additives selected from the group consisting of a functionalized component, a tackifier component, a process oil component, a wax component, an antioxidant component, or a mixture thereof.

18. The adhesive composition of claim 1 , wherein said adhesive composition comprises 99 wt % to 1 wt % of said propylene-based polymer and 1 wt % to 99 wt % of said ethylene-based polymer, based on the weight of said adhesive composition.

19. The adhesive composition of claim 1 , wherein said adhesive composition has a Brookfield viscosity measured by ASTM D-3236 at 177° C. is from 250 to 30,000 mPa·sec.

20. The adhesive composition of claim 1 , wherein said adhesive composition has a melting temperature measured by differential scanning calorimetry at second melt with a heating rate of 10° C./min is no more than 130° C.

21. The adhesive composition of claim 1 , wherein said adhesive composition has one or more of the following properties:
(i) a Brookfield viscosity of 250 to 5000 mPa·sec measured by ASTM D-3236 at 177° C.;
(ii) a percent fiber tear at 25° C. greater than or equal to 85%;
(iii) a percent fiber tear at 2° C. greater than or equal to 80%;
(iv) a percent fiber tear at −18° C. greater than or equal to 75%;
(v) an adhesion set time of 6 seconds or less; and
(vi) a melting temperature (T m ) of 130° C. or less measured by differential scanning calorimetry at second melt with a heating rate of 10° C./min.

22. An adhesive composition comprising:
(a) a propylene-based polymer comprising from 50 wt % to 100 wt % propylene-derived units and from 0 wt % to 50 wt % ethylene-derived units, said propylene-based polymer having a Brookfield viscosity in the range of 250 to 25,000 mPa·sec measured by ASTM D-3236 at 190° C., a heat of fusion in the range of 60 to 150 J/g measured by differential scanning calorimetry at second melt with a heating rate of 10° C./min and a characteristic time (t c ) in the range from 1 to 1000 nanoseconds;
(b) an ethylene-based polymer comprising from 50 wt % to 100 wt % ethylene-derived units and from 0 wt % to 50 wt % octene-derived units, said ethylene-based polymer having a Brookfield viscosity in the range of 250

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Tse Mun F

Classifications

• C09J123/14 Primary

  Copolymers of propene (C09J123/16 takes precedence) · CPC title

• C08L23/06

  Polyethylene · CPC title

• C08L23/12

  Polypropene · CPC title

• C09J123/0815

  Copolymers of ethene with aliphatic 1-olefins · CPC title

• C09J123/12

  Polypropene · CPC title