Preparation method of polypropylene type bonding resin for multi-layer coextrusion barrier packaging

Abstract

The invention discloses a preparation method of polypropylene type bonding resin for multi-layer coextrusion barrier packaging. The raw materials include (by weight percent) 50% to 80% of polypropylene random copolymer, 10% to 30% of functionalized modified atactic polypropylene, 10% to 30% of propylene based elastomer, 1% to 10% of styrene block copolymer and 0.01% to 1% of thermal oxygen stabilizer. The resin is obtained in extruded and granulated manners through a double screw extruder by the plasticating and blending process. The bonding resin is applied to the bonding layers of polypropylene (PP) / Niron (PA) or polypropylene (PP) / ethylene vinyl alcohol copolymer (EVOH) multi-layer coextrusion barrier packaging films (pieces), the processing performance is fine, the transparency is high, thermal resistance is fine, fisheye is few, the bonding performance is excellent, and a good bonding layer material is provided in the field of polypropylene type multi-layer coextrusion barrier packaging.

Description

technical field [0001] The invention belongs to the field of polymer functional materials, relates to the technical field of hot-melt adhesives, in particular to a method for preparing a polypropylene-type adhesive resin for multi-layer co-extruded barrier packaging, which is mainly used as polypropylene (PP) / nylon (PA) Or the adhesive layer of polypropylene (PP) / ethylene-vinyl alcohol copolymer (EVOH) multilayer co-extruded barrier packaging film (sheet). Background technique [0002] In recent years, the proportion of plastic packaging materials replacing traditional packaging materials has been growing rapidly, and high value-added functional plastic packaging materials represented by multi-layer co-extruded barrier functional films (sheets) are increasingly being received by the packaging industry and food favored by the industry. [0003] Multi-layer co-extrusion technology refers to directly using more than three kinds of plastic particles (or powder) as raw materials...

AI Technical Summary

Problems solved by technology

When the bonding strength is not enough, the co-extruded film will delaminate during the production of multi-layer co-extruded film or when stretched and packaged by vacuum, which seriously affects product quality and production efficiency

At present, when using polypropylene multi-layer co-extrusion film or polyethylene multi-layer co-extrusion film to package angular products (such as trotters, beef steaks, and electronic printed circuit boards, etc.), the corners and corners will be damaged when they pass through the vacuum stretching process. Delamination often occurs at the edge, indicating that the bonding strength of the adhesive resin at the edge of the edge is severely reduced or lost due to the relative excessive tensile stress and strain between the layers during vacuum stretching. Therefore, in the prior art The use of polypropylene-type bonding resins and polyethylene-type bonding resins imposes higher requirements

Images