Dynamically Vulcanized Elastomer Laminates for Tire Innerliner Adhesion

Solution Overview

Problem

Thermoplastic resin/thermoplastic resin blends used in tire applications lack flexibility and durability, leading to issues such as adhesion problems during tire manufacturing and appearance defects due to heat resistance limitations, and require additional layers like Mylar® film for release, increasing costs and weight.

Innovation Solution

A dynamically vulcanized alloy film coated with an adhesive layer of less than 10 microns thickness, comprising a thermoplastic elastomer composition with a thermoplastic resin as the continuous phase and a rubber composition as the dispersed phase, using coating methods like gravure or reverse roll coating, and functionalized polyethyleneimine polymers to enhance adhesion and flexibility.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If thermoplastic resin/thermoplastic resin blends are used for gas barrier, then gas permeability is reduced, but flexibility and durability deteriorate

Engineering Contradiction:

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The invention uses a composite material system consisting of a thermoplastic resin layer and a thermoplastic elastomer layer. The thermoplastic resin layer provides gas barrier properties, while the thermoplastic elastomer layer provides flexibility and durability. This composite structure allows both requirements to be satisfied simultaneously by assigning different functions to different layers.

Inventive Principle:

Principle #40Composite materials

2Strength

If thermoplastic elastomer with low melting point is used, then flexibility is improved, but heat resistance deteriorates causing adhesion to vulcanization bladder

Engineering Contradiction:

Core Design Contradiction:

StrengthVSTemperature

Solution Approach 1:

The invention segments the tire innerliner into multiple functional layers: a thermoplastic elastomer layer for flexibility and adhesion to the tire carcass, and a separate thermoplastic resin layer for heat resistance as a release layer. This segmentation allows each layer to perform its specific function without compromising the other, preventing adhesion to the vulcanization bladder while maintaining flexibility.

Inventive Principle:

Principle #1Segmentation

3Strength

If adhesive layer is made too tacky, then adhesion to tire carcass is improved, but adhesion to take-up roll occurs degrading workability

Engineering Contradiction:

Core Design Contradiction:

StrengthVSEase of operation

Solution Approach 1:

The invention applies local quality by using different adhesive compositions in different layers. The thermoplastic elastomer layer contains an adhesive composition optimized for adhesion to the tire carcass, while the thermoplastic resin layer contains an adhesive composition optimized for release from the take-up roll. This local differentiation of adhesive properties allows both requirements to be satisfied.

Inventive Principle:

Principle #3Local quality

4Strength

If adhesive layer thickness is increased, then adhesion performance is improved, but material usage and weight increase

Engineering Contradiction:

Core Design Contradiction:

StrengthVSWeight of moving object

Solution Approach 1:

The invention optimizes the thickness parameter of the adhesive layers to achieve the minimum required adhesion performance. By carefully controlling the thickness of each adhesive layer (typically in the range of micrometers), the invention achieves sufficient adhesion while minimizing material usage and weight. This parameter optimization is combined with selecting adhesive compositions that provide high adhesion strength per unit thickness.

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 solution provides improved durability, flexibility, and reduced gas permeability, preventing adhesion issues and appearance defects while minimizing material usage and weight, thus enhancing tire manufacturing efficiency and performance.

Implementation Method 1

coating at least a portion of an outer surface of a dynamically vulcanized alloy film with an adhesive composition to produce the laminate

Methodology Applied

Scientific EffectAdhesion: Adhesive

Implementation Method 2

a thermoplastic elastomer composition containing a thermoplastic resin as a continuous phase, and a rubber composition dispersed therein, as a dispersed phase

Methodology Applied

Scientific EffectViscoelasticity: Viscoelasticity

Data Source

PatentUS9327554B2Dynamically vulcanized thermoplastic elastomer laminates

Publication Date: 2016.05.03

AI summary

Disclosed herein is a process to produce a laminate comprises coating at least an outer surface of a dynamically vulcanized alloy film with an adhesive composition to produce the laminate, wherein the adhesive layer has a thickness of less than or equal to about 5 microns, wherein the dynamically vulcanized alloy film comprises a thermoplastic elastomer composition containing a thermoplastic resin as a continuous phase, and a rubber composition dispersed therein, as a dispersed phase. A laminate and a pneumatic tire comprising the laminate are also disclosed.