Polyurethane Sandwich Molding With Moisture-Curing Edge Formation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing processes for producing polyurethane sandwich moldings require significant equipment investment and struggle with polyurethane material runoff and dripping, leading to incomplete edge formation and increased waste.
Innovation Solution
A process involving a moisture-curing polyurethane adhesive applied to reinforcing fiber layers, which is cured by contact with water or aqueous solutions, allowing for controlled application and efficient use of polyurethane without the need for expensive equipment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If spray application of polyurethane reaction mixture is used, then complete coverage and edge formation are achieved, but expensive extraction equipment is required and aerosols are generated
Solution Approach 1:
The patent replaces the spray application mechanism (mechanical system generating aerosols) with a moisture-curing adhesive system that uses water or aqueous solutions for curing. This substitution eliminates the need for expensive aerosol extraction equipment while achieving complete coverage through the adhesive's flowability and curing characteristics.
Solution Approach 2:
The patent changes the curing mechanism parameter from spray-based chemical reaction to moisture-curing. By using water or aqueous solutions as the curing agent instead of spray-applied polyurethane reaction mixture, the process eliminates aerosol generation while maintaining complete coverage and clean edge formation through controlled adhesive flow and curing.
2Quantity of substance
If liquid polyurethane reaction mixture is applied to reinforcing element, then coverage is achieved, but running and dripping occurs before molding
Solution Approach 1:
The patent changes the physical state and curing characteristics of the polyurethane material by using a moisture-curing adhesive formulation. This parameter change allows the adhesive to remain controllable during application (reducing running and dripping) while still providing complete coverage, as the curing process is triggered by moisture rather than immediate chemical reaction.
Solution Approach 2:
The patent applies the moisture-curing adhesive to the reinforcing element before final molding, allowing controlled application and positioning. The adhesive remains in a manageable state during application and only cures when exposed to moisture during or after the molding process, preventing running and dripping while ensuring complete coverage.
3Shape
If compression is applied to core layer, then shape definition is improved, but sealing at edges becomes difficult without sufficient free-flowing polyurethane
Solution Approach 1:
The patent changes the adhesive formulation to a moisture-curing system with optimized flowability and curing characteristics. This parameter change allows the adhesive to maintain sufficient free-flowing properties during compression to seal edges properly, while still enabling the compression process to define the core layer shape. The moisture-curing mechanism ensures complete curing even in compressed regions.
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
Enables efficient production of polyurethane sandwich moldings with clean edge formation and reduced waste, eliminating aerosol formation and odor, while ensuring consistent stiffening and targeted application of polyurethane.
Implementation Method 1
a moisture-curing polyurethane adhesive is applied to a reinforcing fiber layer... for the curing the moisture-curing polyurethane adhesive is brought into contact with water or with a solution comprising water
Data Source
AI summary
Described herein is a process for producing polyurethane sandwich moldings including at least one core layer and at least one reinforcing fiber layer, where (i) at least one reinforcing fiber layer is applied onto a core layer and a moisture-curing polyurethane adhesive is applied to a reinforcing fiber layer, (ii) the part from (i) is placed into a mold and pressed in the mold and the moisture-curing polyurethane adhesive is cured, and (iii) the molding from (ii) is removed from the mold and optionally subjected to further operations, where the moisture-curing polyurethane adhesive is applied before or after application of the reinforcing fiber layer onto the at least one core layer and for the curing the moisture-curing polyurethane adhesive is brought into contact with water or with a solution comprising water. Also described herein are a polyurethane sandwich molding obtainable by such a process and a method of using a polyurethane sandwich molding in vehicles.