Hot melt adhesive
A hot melt adhesive material and articles made using the hot melt adhesive to assemble structures in an article. The adhesive material typically is manufactured by blending amorphous polymer with a heterophase polymer having crystallinity into an adhesive composition.
1. A hot melt adhesive composition consisting essentially of:
(i) about 90 to 10 wt. % of an amorphous polyolefin copolymer composition comprising 50 to 70 wt. % 1-butene;
(ii) about 10 to 90 wt. % of a heterophase polypropylene copolymer composition comprising propene and a comonomer comprising ethylene, 1-hexene or 1-octene and comprising amorphous blocks and crystalline blocks; and
(iii) about 0.1 to 30 wt. % of a polyisobutylene plasticizer made with an AlCl 3 ; wherein the adhesive provides cohesive strength from the heterophase polyolefin copolymer and adhesive strength from the amorphous polypropylene copolymer.
2. The adhesive of claim 1 wherein the heterophase polyolefin copolymer comprises at least about 5 wt. % crystalline sequences or blocks.
3. The adhesive of claim 1 wherein the heterophase polypropylene copolymer comprises greater than 40 wt. % of propene and less than 60 wt. % of the comonomer and has a crystallinity of greater than 10%.
4. The adhesive of claim 1 wherein the adhesive is substantially free of a tackifier.
5. The adhesive of claim 1 wherein there is about 50 to 80 wt. % of the amorphous polyolefin copolymer and about 10 to 50 wt. % of the heterophase polypropylene copolymer.
6. An article comprising a substrate and a film, fiber, cellulose sheet or non-woven having an adhesive bond there between comprising the adhesive of claim 1 wherein the adhesive provides cohesive strength from the heterophase polypropylene copolymer and adhesive strength from the amorphous polyolefin copolymer.