Preparation method of solvent-free double-component polyurethane cooking adhesive

Abstract

The invention discloses a method for preparing a solvent-free two-component polyurethane cooking adhesive, and discloses in detail the preparation of glue A, glue B and the preparation of the target object, wherein the glue A is made of polyether polyol with a molecular weight of 1000-2000 , Liquefied MDI (NCO% = 33.5) and hexamethylene diisocyanate trimer are dehydrated for 2 hours at 100-120°C under vacuum-0.1MPa conditions, and the water content of the detection system is less than 0.05% is qualified, and the temperature is lowered to 40 prepared at ℃; glue B is prepared from polyethylene glycol, 1,3-butanediol, adipic acid, and isophthalic acid with tetrabutyl titanate catalyst; 7 Mix to obtain a solvent-free polyurethane adhesive. The advantages of this new solvent-free two-component polyurethane retort adhesive: excellent retort resistance and peel strength. The preparation process is simple, cheap and pollution-free.

Description

technical field [0001] The invention relates to a preparation method of a solvent-free two-component polyurethane cooking adhesive, which belongs to the field of material and food research. Background technique [0002] Compared with traditional dry lamination, solvent-free lamination has many advantages in reducing costs, improving product quality, environmental protection, production safety and stability, etc. The adhesive used in solvent-free lamination does not contain solvents, so there is no pollution to the packaging, and it is more suitable for food packaging. However, ordinary solvent-free adhesives can no longer meet market demand, especially special adhesive products for retort packaging bags. The peel strength of packaging bags made of ordinary glue will be greatly reduced after high-temperature cooking, and even delamination will occur in severe cases, which directly affects the normal use of flexible packaging products. For example, although the common flexib...

AI Technical Summary

Problems solved by technology

However, ordinary solvent-free adhesives can no longer meet the market demand, especially special adhesive products for retort packaging bags.

The peel strength of packaging bags made of ordinary glue will be greatly reduced after high-temperature cooking, and even delamination will occur in severe cases, which directly affects the normal use of flexible packaging products

For example, although the common flexible packaging glue currently on the market is a solvent-free two-component glue, its cooking resistance is poor. At present, many cooked foods, especially meat flexible packaging for cooked foods, have higher requirements for cooking resistance. , it is required that the peel strength after cooking at 121°C should be greater than or equal to 5 (N.15mm), and no delamination phenomenon can occur. However, the peel strength of existing products before cooking is less than 4 (N.15mm), and the peeling strength after cooking at 121°C lower strength