Hot Melt Adhesives
View Patent ↗A hot melt adhesive based on a functionalized metallocene polyethylene copolymer finds use in packaging applications where high heat resistance, as well as good cold tolerance, is required.
1. A low application temperature hot melt adhesive comprising a functionalized metallocene polyethylene copolymer, a tackifier and a wax, wherein the polyethylene copolymer is prepared from ethylene and 1-octene monomers, the adhesive having a viscosity of from about 700 cP to about 2000 cP at a temperature of 250° F.
2. The adhesive of claim 1 wherein the functionalized metallocene polyethylene copolymer comprises a functional group selected from the group consisting of acrylic acid, acetate, sulfonate, maleic anhydride, fumaric acid and mixtures thereof.
3. The adhesive of claim 2 wherein the functional group is maleic anhydride.
4. The adhesive of claim 2 wherein the functional group is fumaric acid.
5. The adhesive of claim 2 wherein the functionalized metallocene polyethylene copolymer comprises from about 0.3 to about 8 weight % of a functional group, based on the weight of the non-functionalized metallocene polyethylene copolymer.
6. The adhesive of claim 5 wherein the functionalized metallocene polyethylene copolymer comprises from about 0.5 to about 3 weight % of said functional group based on the weight of the non-functionalized metallocene polyethylene copolymer.
7. The adhesive of claim 1 wherein the tackifier is selected from the group consisting of rosin modified tackifier, C 5 hydrocarbon derived tackifier, C 9 aromatic modified C 5 hydrocarbon derived tackifier and mixtures thereof.
8. The adhesive of claim 1 wherein the wax is selected from the group consisting of a paraffin wax, synthetic wax, microcrystalline wax and mixtures thereof.
9. The adhesive of claim 8 wherein the wax is a paraffin wax.
10. The adhesive of claim 8 wherein the wax is a synthetic wax.
11. The adhesive of claim 1 further comprising a filler, a plasticizer, a pigment, a dyestuff or a mixture thereof.
12. The adhesive of claim 1 further comprising a non-functionalized metallocene polyethylene copolymer.
13. A low application temperature hot melt adhesive composition comprising, based on the total weight of the composition,
(a) from about 20 to about 50 wt % of a maleic anhydride modified functionalized metallocene polyethylene copolymer, wherein the polyethylene copolymer is prepared from ethylene and 1-octene monomers,
(b) from about 20 to about 40 wt % of a wax; and
(c) from about 20 to about 45 wt % of a tackifier,
wherein said maleic anhydride modified functionalized metallocene polyethylene copolymer contains from about 0.3 to 8 weight %, based on weight of the non-functionalized metallocene polyethylene copolymer, of maleic anhydride functional group.