Spray Polyester Polyurethane Elastomer Tunable Modulus

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current spray polyurethane elastomers face limitations in achieving tunable tensile modulus, high resistance to permanent deformation, and suitable density for various applications, particularly in replacing coated fabrics and requiring improved mechanical properties and adhesion to different surfaces.

Innovation Solution

Development of spray polyester polyurethane elastomers with a unique composition involving an isocyanate functional urethane prepolymer derived from monomeric diphenylmethane diisocyanate and a polyester polyol, allowing for air injection to reduce density and enhance mechanical properties, adhesion, and resistance to harsh environments.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If spray polyether polyurethane and spray polyurea are used, then processing is enabled, but mechanical properties such as tensile strength, tear strength, and elongation performance are insufficient

Engineering Contradiction:

Improvemechanical propertiesVSAvoidprocessing capability

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The patent changes the chemical composition parameters by using polyester polyols with specific hydroxyl values (50-200 mg KOH/g) and controlling the NCO/OH ratio (105-130), which fundamentally alters the mechanical properties to achieve superior tensile strength, tear strength, and elongation while maintaining spray processability

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention creates a composite polyurethane system combining polyester polyols with specific chain extenders and crosslinkers, achieving a synergistic effect that provides both excellent mechanical properties and processability, overcoming the limitations of single-component systems

Inventive Principle:

Principle #40Composite materials

2Strength

If polyester polyol with high viscosity is used, then mechanical properties improve, but processability and spray characteristics deteriorate

Engineering Contradiction:

Improvemechanical propertiesVSAvoidprocessability

Core Design Contradiction:

StrengthVSEase of operation

Solution Approach 1:

The patent optimizes the hydroxyl value parameter of polyester polyol to a specific range (50-200 mg KOH/g) that balances viscosity and reactivity, enabling the system to maintain good mechanical properties while achieving acceptable processability and spray characteristics

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention introduces chain extenders and crosslinkers as intermediary substances that modify the polyol-isocyanate reaction, enabling better processability while maintaining mechanical integrity through controlled crosslinking density

Inventive Principle:

Principle #24Intermediary (Mediator)

3Weight of moving object

If density is reduced by air injection, then weight and cost decrease, but mechanical properties and strength may deteriorate

Engineering Contradiction:

ImprovedensityVSAvoidmechanical properties

Core Design Contradiction:

Weight of moving objectVSStrength

Solution Approach 1:

The patent modifies the chemical composition parameters (polyol hydroxyl value, NCO/OH ratio, crosslinker concentration) to compensate for density reduction, maintaining mechanical properties even at lower densities achieved through air injection

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention uses temporary air injection during spray application to achieve low density, with the air bubbles collapsing during curing to leave a lightweight cellular structure that maintains strength through optimized polymer architecture

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

4Stability of the object's composition

If conventional spray polyurethane is used, then adhesion is achieved, but resistance to permanent deformation and creep is insufficient

Engineering Contradiction:

Improveresistance to permanent deformationVSAvoidadhesion

Core Design Contradiction:

Stability of the object's compositionVSEase of manufacture

Solution Approach 1:

The patent optimizes crosslinker concentration and type, along with catalyst selection, to create a highly crosslinked network structure that provides exceptional resistance to creep and permanent deformation while maintaining good adhesion to substrates

Inventive Principle:

Principle #35Parameter changes

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 spray polyester polyurethane elastomers exhibit superior tensile and tear strength, elongation performance, abrasion resistance, and tunable modulus, offering improved mechanical properties and adhesion to various surfaces, while maintaining or exceeding the performance of full-density spray polyether elastomers.

Implementation Method 1

spray polyester polyurethane elastomers produced in accordance with the present disclosure

Methodology Applied

Scientific EffectPolycondensation:

Implementation Method 2

air injection in order to reduce density to the range of 0.60-0.90 g/cm3

Methodology Applied

Scientific EffectAeration: Aeration

Data Source

PatentUS20220340704A1Spray polyurethane elastomers and methods for producing the same

Publication Date: 2022.10.27 BASF SE

AI summary

The present disclosure relates to spray polyether and polyester polyurethane elastomeric articles and associated methods of producing such elastomer articles. More specifically, the invention provides spray polyester polyurethane elastomer articles that exhibit excellent tensile and tear strength, superior elongation performance and improved abrasion resistance performance with tunable tensile modulus.