Pressure sensitive adhesive composition with silane grafted olefin block copolymer

Patent metadata

Field	Value
Publication number	US-9688803-B2
Application number	US-201314651999-A
Country	US
Kind code	B2
Filing date	Dec 9, 2013
Priority date	Dec 31, 2012
Publication date	Jun 27, 2017
Grant date	Jun 27, 2017

Abstract

The present disclosure is directed to a pressure sensitive adhesive composition. The pressure sensitive adhesive composition includes an olefin block copolymer, a silane-grafted olefin block copolymer, a tackifier, and an oil. The pressure sensitive adhesive composition has a shear adhesion greater than 60 minutes. The pressure sensitive adhesive composition exhibits improved shear adhesion while simultaneously maintaining loop tack greater than 4.0 N/25 mm.

First claim

The invention claimed is:

1. A pressure sensitive adhesive composition comprising:
an ethylene/α-olefin multi-block copolymer comprising hard segments and soft segments, the hard segments and soft segments comprising ethylene, the ethylene/α-olefin multi-block copolymer having a melt index from 0.1 g/10 min to 30.0 g/10 min;
a silane-grafted ethylene/α-olefin multi-block copolymer comprising hard segments and soft segments, the hard segments and soft segments comprising ethylene, the base ethylene/α-olefin multi-block copolymer having a melt index from 0.1 g/10 min to 30.0 g/10 min;
a tackifier;
an oil;
wherein the composition has a shear adhesion greater than 60 minutes.

2. The pressure sensitive adhesive composition of claim 1 comprising
25 wt % to 35 wt % of the ethylene/α-olefin multi-block copolymer;
1 wt % to 5 wt % of the silane grafted ethylene/α-olefin multi-block copolymer;
55 wt % to 65 wt % of the tackifier;
5 wt % to 15 wt % of the oil; and
0.1 wt % to 0.5 wt % antioxidant.

3. The pressure sensitive adhesive composition of claim 1 wherein the ethylene/α-olefin multi-block copolymer and the base polymer of the silane grafted ethylene/α-olefin multi-block copolymer are the same.

4. The pressure sensitive adhesive composition of claim 3 wherein the ethylene/α-olefin multi-block copolymer is an ethylene/octene multi-block copolymer.

5. The pressure sensitive adhesive composition of claim 1 wherein the tackifier is a C 9 hydrogenated tackifier.

6. The pressure sensitive adhesive composition of claim 1 wherein the composition has a loop tack greater than 4.0 N/25 mm.

7. The pressure sensitive adhesive composition of claim 1 wherein the composition has a shear adhesion from 70 minutes to 90 minutes.

8. The pressure sensitive adhesive composition of claim 1 wherein the composition has a peel strength (adhesion to stainless steel) greater than 25 N/25 mm.

9. The pressure sensitive adhesive composition of claim 1 wherein the composition has a peel strength (adhesion to polyethylene) greater than 2.0 N/25 mm.

10. The pressure sensitive adhesive composition of claim 1 wherein the composition has a loop tack greater than 4.0 N/25 mm and a shear adhesion greater than 80 minutes.

11. The pressure sensitive adhesive composition of claim 1 wherein the ethylene/α-olefin multi-block copolymer and the base ethylene/α-olefin multi-block copolymer each has a melt index from 0.5 g/10 min to 5.0 g/10 min.

12. The pressure sensitive adhesive composition of claim 1 wherein the base polymer of the silane grafted ethylene/α-olefin multi-block copolymer is an ethylene/octene multi-block copolymer.

Assignees

• Dow Global Technologies Llc

Inventors

• Mclennaghan Allan W

Classifications

• C08L2666/24

  Graft or block copolymers according to groups C08L51/00, C08L53/00 or C08L55/02; Derivatives thereof · CPC title

• C08F297/083 Primary

  the monomers being ethylene or propylene · CPC title

• C09J7/0221

  Chemistry & Metallurgy · mapped topic

• C08K5/01

  Hydrocarbons {(C08K5/0091 takes precedence)} · CPC title

• C08K5/138

  Phenolates · CPC title