Adhesive composition
The present invention relates to an adhesive composition comprising a. a polyethylene resin (A) which has been grafted with an acid grafting agent and b. an epoxy resin (B) in an amount of 0.01 to 15 wt. % of the adhesive total composition, wherein the adhesive composition is having a MFR 5 of 0.1 to 12 g/10 min. Furthermore, the invention relates to an article, in particular a multilayer pipe, comprising an adhesive layer which comprises said adhesive composition and the use of said adhesive composition for the production of an adhesive layer, in particular of an adhesive layer of a pipe.
1. A pipe comprising an adhesive layer comprising an adhesive composition comprising
a. a polyethylene resin (A) which has been grafted with an acid grafting agent and
b. an epoxy resin (B) in an amount of 0.01 to 20 wt. % of the adhesive total composition,
wherein the adhesive composition has a MFR 5 of 0.1 to 12 g/10 min; and wherein the polyethylene resin (A) comprises: a low molecular weight ethylene polymer having a density of 900 to 950 kg/m 3 and an MFR 2 of 25 to 300 g/10 min; and a high molecular weight polymer having a density of 870 to 940 kg/m 3 and an MFR 2 of 0.1 to 3.0 g/10 min.
2. The pipe of claim 1 , wherein the polyethylene resin (A) comprises 35 to 55 wt. % of the low molecular weight ethylene polymer and 45 to 65 wt. % of the high molecular weight ethylene polymer based on the weight of the polyethylene resin (A).
3. The pipe of claim 1 , wherein the polyethylene resin (A) comprises 44 to 50 wt. % of the low molecular weight ethylene polymer and 50 to 56 wt. % of the high molecular weight ethylene polymer based on the weight of the polyethylene resin (A).
4. The pipe according to claim 1 , wherein the acid grafting agent is selected from unsaturated carboxylic acids and derivatives thereof.
5. The pipe according to claim 1 , wherein the amount of said acid grafting agent is from 0.01 to 3.0 wt. %, of the adhesive composition.
6. The pipe according to claim 1 , wherein the epoxy resin (B) is a Bisphenol A resin.
7. The pipe according to claim 1 , wherein the epoxy resin (B) is present in an amount of 0.05 to 20 wt. % of the adhesive composition.
8. The pipe of claim 1 , wherein the amount of the epoxy resin (B) in the adhesive composition is 0.1 to 15 wt. %.
9. The pipe of claim 1 , wherein the amount of the epoxy resin (B) in the adhesive composition is 0.15 to 10 wt. %.
10. The pipe of claim 1 , wherein the amount of the epoxy resin (B) in the adhesive composition is 0.2 to 6 wt. %.
11. The pipe according to claim 1 , wherein the adhesive composition further comprises an elastomeric resin (C).
12. The pipe according to claim 11 wherein the elastomeric resin (C) is present in an amount of 2 to 60 wt. %, of the total composition.
13. The pipe of claim 11 , wherein the amount of the elastomeric resin (C) in the adhesive composition is 10 to 50 wt. %.
14. The pipe of claim 11 , wherein the amount of the elastomeric resin (C) in the adhesive composition is 20 to 40 wt. %.
15. The pipe according to claim 1 , wherein the adhesive composition has a density of 910 to 990 kg/m 3 .
16. The pipe according to claim 1 , wherein the adhesive layer is coated with at least one surface layer comprising a polyethylene composition.
17. A pipe comprising an adhesive layer comprising an adhesive composition comprising
a polyethylene resin (A) which has been grafted with an acid grafting agent, the polyethylene resin (A) comprising:
44 to 50 wt. % based on the weight of the polyethylene resin (A) of a low molecular weight ethylene polymer having a density of 900 to 950 kg/m 3 and an MFR 2 of 25 to 300 g/10 min; and
50 to 56 wt. % based on the weight of the polyethylene resin (A) of a high molecular weight ethylene polymer having a density of 870 to 940 kg/m 3 and an MFR 2 of 0.1 to 3.0 g/10 min;
0.2 to 6 wt. % of an epoxy resin (B) based on the overall adhesive composition; and
20 to 40 wt. % of an elastomeric resin (C) based on the overall adhesive composition;
wherein the adhesive composition has a MFR5 of 0.1 to 12 g/10 min.