Polyurethane Adhesive Composition for PE-Metal Laminates
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing adhesive compositions fail to provide optimal bond strength, heat seal strength, and low coefficient of friction for laminates involving polyethylene and metal substrates, particularly in solvent-free formulations.
Innovation Solution
A polyurethane adhesive composition comprising a polyurethane dispersion made from a reaction product of monomeric aromatic diisocyanate, polyether polyol, polyester polyol with aromatic and aliphatic groups, polyamine, and ionic surfactant, combined with a polyisocyanate crosslinker, which is applied to substrates like metal foils and polyethylene films to form strong and durable laminates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional adhesive compositions are used, then general bonding capability is provided, but optimal bond strength, heat seal strength, and low coefficient of friction for PE-metal laminates cannot be achieved
Solution Approach 1:
The adhesive composition uses different polyol components (polyether polyol for flexibility and low COF, polyester polyol for adhesion to PE and metal) in specific proportions to create localized functional properties within the same adhesive formulation, enabling it to simultaneously satisfy different substrate requirements for bond strength, heat seal strength, and friction characteristics
Solution Approach 2:
The invention creates a composite adhesive system combining polyurethane dispersion with specific ratios of polyether polyol, polyester polyol, polyamine, and ionic surfactant, where each component contributes specific properties that collectively achieve optimal performance for bonding dissimilar substrates like PE and metal
2Object-affected harmful factors
If solvent-free adhesive formulations are used, then environmental and safety requirements are met, but optimal performance in bond strength, heat seal strength, and coefficient of friction cannot be achieved
Solution Approach 1:
The invention modifies the chemical composition parameters of the solvent-free adhesive by incorporating ionic surfactant (0.5-10% by dry weight) and specific ratios of polyols, which change the physical and chemical properties of the adhesive to achieve low coefficient of friction and optimal heat seal strength without requiring solvents
3Object-affected harmful factors
If polyurethane dispersion is used as the base adhesive, then solvent-free formulation is achieved, but optimal performance for bonding PE and metal substrates cannot be achieved without additional components
Solution Approach 1:
The ionic surfactant acts as an intermediary component in the solvent-free adhesive system, mediating between the polyurethane dispersion and the substrates (PE and metal) to enhance wetting, adhesion, and overall bond strength while maintaining the solvent-free formulation
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The composition achieves enhanced bond strength, heat seal strength, and reduced coefficient of friction, making it suitable for bonding polyethylene and metal substrates while being solvent-free, thus meeting environmental and safety requirements.
Implementation Method 1
A polyurethane adhesive composition comprising a polyurethane dispersion and from 1.2% to 20% by dry weight based on total dry weight of the polyurethane dispersion, a polyisocyanate crosslinker
Implementation Method 2
from 0.5% to 10% of an ionic surfactant
Data Source
AI summary
Provided is a polyurethane adhesive composition comprising a polyurethane dispersion and from 1.2wt% to 20wt% of a polyisocyanate crosslinker. Said polyurethane dispersion is a reaction product of from 10wt% to 40wt% of a monomelic aromatic diisocyanate, from 30wt% to 65wt% of a polyefher polyol, from 15wt% to 30wt% of a polyester polyol having at least one aromatic group and one aliphatic group, from 0.1% to 8% of a polyamine, and from 0.5% to 10% of an ionic surfactant.