Method for preparing an adhesive polyolefin, adhesive polyolefin, use thereof, and manufactured article

Patent metadata

Field	Value
Publication number	US-11319469-B2
Application number	US-201214441060-A
Country	US
Kind code	B2
Filing date	Nov 6, 2012
Priority date	Nov 6, 2012
Publication date	May 3, 2022
Grant date	May 3, 2022

Abstract

The present invention refers to co-extrusion of one or more polyolefins with one or more adhesive layers to improve the adhesiveness of the polyolefins in metal, epoxy resin, glass, ceramics, paper, wood, thermoplastic resin, fabric, non-woven fabric, varnishes and formica.More specifically, the present invention refers to a method of co-extruding at least one polyolefin with an adhesive layer, thereby enhancing the adhesion properties of the polyolefin, particularly in polyurethane foams such that a polar surface is imparted to the obtained adhesived polyolefin.

First claim

What is claimed is:

1. A method for preparing a product comprising a polyolefin and an adhesive, wherein the product is a co-extruded structure including a polyolefin layer and an ethylene vinyl acetate (EVA) adhesive layer, the method further comprising molding a polyurethane foam on the adhesive layer of the co-extruded structure, wherein molding the polyurethane foam comprises combining a polyol and an isocyanate in a mold, and curing the combined material, wherein the viscosity ratio between the polyolefin and the adhesive is from 0.5 to 2, and the vinyl acetate content in EVA is 8 to 21 wt %, and
wherein said EVA has a fluidity rate between 0.1 and 800 g/10 min measured at 190° C./2.16 Kg, and the adhesive layer of the co-extruded structure is subjected to a treatment selected from corona, flame, plasma, radiation and combinations thereof.

2. The method as recited in claim 1 , wherein the polyolefin is selected from the group consisting of PP, PE, HDPE, LDPE, LLDPE and combinations thereof.

3. The method as recited in claim 1 , wherein said adhesive further comprises a material selected from the group consisting of copolymers, primers, mineral fillers, organic or inorganic compounds, silanes, polar additives and combinations thereof.

4. The method as recited in claim 1 , wherein the adhesive layer thickness is between 0.5 and 20% of the co-extruded structure.

5. The method as recited in claim 1 , wherein the co-extruded structure is a calendered co-extruded structure.

6. The method as recited in claim 5 , wherein the calendered co-extruded structure has a rough superficial finish.

7. The method as recited in claim 5 , wherein the calendered co-extruded structure has a smooth superficial finish.

8. The method as recited in claim 1 , wherein the molding of polyurethane foam in the co-extruded structure takes place with the co-extruded structure at temperatures between 20° C. and 70° C.

9. The method as recited in claim 1 , wherein the polyol and the isocyanate are combined in a polyol:isocyanate mass ratio between 100:101 and 100:200.

10. The method as recited in claim 1 , wherein molding takes place in a pressure above 0.1 bar and a temperature above 70° C.

Assignees

• Braskem Sa

Inventors

• Martinelli Carolina Barreto Roma
• Farah Marcelo

Classifications

• B32B27/32 Primary

  comprising polyolefins {(comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30)} · CPC title

• B29C48/0012

  combined with shaping by internal pressure generated in the material, e.g. foaming · CPC title

• B32B7/12

  using interposed adhesives or interposed materials with bonding properties · CPC title

• B29L2009/00

  Layered products · CPC title

• B32B27/306

  comprising vinyl acetate or vinyl alcohol (co)polymers · CPC title