Polypropylene based hot-melt adhesive composition

Patent metadata

Field	Value
Publication number	US-10000674-B1
Application number	US-201615737067-A
Country	US
Kind code	B1
Filing date	Jul 27, 2016
Priority date	Jul 30, 2015
Publication date	Jun 19, 2018
Grant date	Jun 19, 2018

Abstract

The invention relates to an adhesive composition wherein such composition comprises at least one polypropylene copolymer and wherein such adhesive composition has improved overall bond performance. It further relates to an article comprising said adhesive composition, as well as to a process for producing such article. It even further relates to the use of the adhesive composition in the preparation of an article.

First claim

The invention claimed is:

1. An adhesive composition comprising at least one polypropylene copolymer, wherein such polypropylene copolymer has:
a) at least one comonomer selected from the group consisting of ethylene and C 4 -C 12 alpha-olefin,
b) a total comonomer content in the range of 4.5 to 20.0 wt %,
c) Vicat A temperature >80° C., as measured according to ISO 306,
d) storage modulus (G′23) in the range of 100 to 1000 MPa as measured at 23° C. according to ISO 6721-02 and ISO 6721-07,
e) melting temperature in the range of 120 to 160° C. as measured according to ISO 11357-3 and at least one of: a polymer other than the at least one polypropylene copolymer, a tackifying resin, a plasticizer, an additive, or a filler.

2. The adhesive composition according to claim 1 wherein the polypropylene copolymer has a tensile modulus (E) in the range of 200 to 1000 MPa as measured according to ISO 527 1 at 23° C.

3. The adhesive composition according to claim 1 wherein the polypropylene copolymer is a polypropylene copolymer-1 (PC-1) having at least one comonomer selected from the group consisting of ethylene, a C 4 -C 12 alpha-olefin, and a combination thereof and wherein such polypropylene copolymer-1 (PC-1) has a Flexibility >0.8 which is calculated according to the equation:
Flexibility=EAY*100000/(TSY* E )

wherein:
EAY is the elongation at yield value,
TSY is the tensile strength at yield value, in MPa and
E is the tensile modulus value, in MPa.

4. The adhesive composition according to claim 3 wherein the polypropylene copolymer-1 (PC-1) has:
a) a glass transition temperature T g1 in the range of −12 to −2° C. and
b) a glass transition temperature T g2 in the range of −65 to −20° C.

5. The adhesive composition according to claim 3 wherein the polypropylene copolymer-1 (PC-1) has:
a) storage modulus (G′23) in the range of 150 to 450 MPa as measured at 23° C. according to ISO 6721-02 and ISO 6721-07 and
b) melting temperature in the range of 135 to 155° C. as measured according to ISO 11357-3.

6. The adhesive composition according to claim 1 wherein the polypropylene copolymer is a polypropylene copolymer-2 (PC-2) comprising units derived from propylene, ethylene and at least one comonomer selected from linear or branched C 4 -C 12 alpha-olefin and wherein such polypropylene copolymer-2 (PC-2) has:
a) a glass transition temperature Tg in the range of −12 to 0° C. and
b) a total comonomer content in the range of 6.0 to 15.0 wt %.

7. The adhesive composition according to claim 6 wherein the polypropylene copolymer-2 (PC-2) has:
a) storage modulus (G′23) in the range of 300 to 600 MPa as measured at 23° C. according to ISO 6721-02 and ISO 6721-07 and
b) melting temperature in the range of 125 to 135° C. as measured according to ISO 11357-3.

8. The adhesive composition according to claim 6 wherein the polypropylene copolymer-2 (PC-2) has a tensile modulus (E) in the range of 500 to 1000 MPa as measured according to ISO 527-1 at 23° C.

9. The adhesive composition according to claim 6 wherein the comonomers in the polypropylene copolymer-2 (PC-2) are ethylene and C 4 alpha-olefin.

10. The adhesive composition according to claim 1 wherein the at least one polymer other than the at least one polypropylene copolymer has
a) melting temperature <120° C. as measured according to ISO 11357-3,
b) storage modulus (G′23) <50 MPa as measured at 23° C. according to ISO 6721-02 and ISO 6721-07,
c) density <0.96 g/cm 3 as measured according to ISO 1183D and
d) an MFR 2 in the range of 0.20 to 2000 g/10 min as measured according to ISO 1133.

11. The adhesive composition according to claim 1 wherein the adhesive composition has:
a) at least one polymer other than the at least one polypropylene copolymer present in the range of 0.01 to 50.0 wt %, the percentage of the at least one polymer other than the at least one polypropylene copolymer is calculated based on the total amount of polypropylene copolymer and of at least one polymer other than the at least one polypropylene copolymer comprised in the adhesive composition and
b) Flexibility >0.5 and which is calculated according to the equation:
Flexibility=EAY*100000/(TSY* E )

wherein:
EAY is the elongation at yield value,
TSY is the tensile strength at yield value, in MPa and
E is the tensile modulus value, in MPa.

12. An article comprising an adhesive composition and at least one substrate, wherein the adhesive composition comprises
at least one polypropylene copolymer, wherein such polypropylene copolymer has:
a) at least one comonomer selected from the group consisting of ethylene and C 4 -C 12 alpha-olefin,
b) a total comonomer content in the range of 4.5 to 20.0 wt %,
c) Vicat A temperature >80° C., as measured according to ISO 306,
d) storage modulus (G′23) in the range of 100 to 1000 MPa as measured at 23° C. according to ISO 6721-02 and ISO 6721-07,
e) melting temperature in the range of 120 to 160° C. as measured according to ISO 11357-3; and

at least one of: a polymer other than the at least one polypropylene copolymer, a tackifying resin, a plasticizer, an additive, or a filler.

13. A process to produce an article wherein the process comprises at least the step of applying at least one adhesive composition on at least one surface of at least one substrate,
wherein the adhesive composition comprises
at least one polypropylene copolymer, wherein such polypropylene copolymer has:
a) at least one comonomer selected from the group consisting of ethylene and C 4 -C 12 alpha-olefin,
b) a total comonomer content in the range of 4.5 to 20.0 wt %,
c) Vicat A temperature >80° C., as measured according to ISO 306,
d) storage modulus (G′23) in the range of 100 to 1000 MPa as measured at 23° C. according to ISO 6721-02 and ISO 6721-07,
e) melting temperature in the range of 120 to 160° C. as measured according to ISO 11357-3; and

at least one of: a polymer other than the at least one polypropylene copolymer, a tackifying resin, a plasticizer, an additive, or a filler.

14. A method comprising preparing an article according to claim 12 with an adhesive composition, wherein the adhesive composition comprises
at least one polypropylene copolymer, wherein such polypropylene copolymer has:
a) at least one comonomer selected from the group consisting of ethylene and C 4 -C 12 alpha-olefin,
b) a total comonomer content in the range of 4.5 to 20.0 wt %,
c) Vicat A temperature >80° C., as measured according to ISO 306,
d) storage modulus (G′23) in the range of 100 to 1000 MPa as measured at 23° C. according to ISO 6721-02 and ISO 6721-07,
e) melting temperature in the range of 120 to 160° C. as measured according to ISO 11357-3; and

at least one of: a polymer other than the at least one polypropylene copolymer, a tackifying resin, a plasticizer, an additive, or a filler.

15. A process to prepare an adhesive composition according to claim 1 comprising combining at least one polypropylene copolymer with at least one of: a polymer other than the at least one polypropylene copolymer, a tackifying resin, a plasticizer, an additive or a filler.

16. The adhesive composition according to claim 2 wherein the polypropylene copolymer is a polypropylene copolymer-1 (PC-1) having at least one comonomer selected from the group consisting of ethylene, a C 4 -C 12 alpha-olefin, and a combination thereof and wherein such polypropylene copolymer-1 (PC-1) has a Flexibility >0.8 which is calculated according to the equation:
Flexibility=EAY*100000/(TSY* E )

Assignees

• Borealis Ag

Inventors

• Wang Jingbo
• Ek Carl-Gustaf
• Sönmez Anil
• Bernreitner Klaus
• Reichelt Norbert

Classifications

• C08K5/0025

  Crosslinking or vulcanising agents; including accelerators · CPC title

• C09D191/08

  Mineral waxes · CPC title

• C08L23/0869

  with unsaturated acids, e.g. [meth]acrylic acid; with unsaturated esters, e.g. [meth]acrylic acid esters · CPC title

• C09J123/142 Primary

  at least partially crystalline copolymers of propene with other olefins · CPC title

• C08L91/06

  Waxes · CPC title