Functionalized Lignin Bead Filler for Pneumatic Tire Rigidity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current compounds for pneumatic tire structural components, such as the bead filler, face processability issues due to separate addition of methylene acceptor and donor compounds, leading to non-optimal formation of bi-component resins and suboptimal rigidity.

Innovation Solution

Replaces bi-component resin with functionalized lignin, specifically Kraft lignin modified with alkyne groups, added during the productive blending step, along with a cross-linkable unsaturated-chain polymer, reinforcing filler, and vulcanization system, to enhance rigidity and sustainability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If bi-component resin is used to achieve high rigidity, then rigidity is improved, but processability deteriorates due to separate addition requirements

Engineering Contradiction:
ImproverigidityVSAvoidprocessability
Core Design Contradiction:
StrengthVSEase of manufacture

Solution Approach 1:

The patent combines the methylene acceptor and donor functions into a single lignin molecule through chemical modification. The lignin is functionalized to contain both the acceptor groups (from original phenolic hydroxyls) and donor groups (from introduced alkyne functionality), eliminating the need for separate addition steps while maintaining cross-linking capability and rigidity enhancement.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent segments the functional groups within the lignin molecule itself, creating distinct methylene acceptor and donor sites on the same polymer chain. This molecular-level segmentation allows both functions to coexist in a single additive, simplifying the compounding process while enabling controlled cross-linking through the vulcanization system.

Inventive Principle:
Principle #1Segmentation

2Reliability

If bi-component resin components are added in separate blending steps, then cross-linking control is improved, but manufacturing complexity increases

Engineering Contradiction:
Improvecross-linking controlVSAvoidmanufacturing complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges the two separate resin components into a single functionalized lignin product. This consolidation reduces the number of blending steps from two (one for acceptor, one for donor) to a single step where the complete cross-linking functionality is introduced at once, simplifying manufacturing while maintaining reliable cross-linking control through the vulcanization process.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The methylene donor and acceptor functionalities are pre-installed on the lignin molecule during its chemical modification phase, before the rubber compounding process. This preliminary functionalization ensures that both cross-linking functions are present and ready to react simultaneously during vulcanization, eliminating the need for sequential addition steps.

Inventive Principle:
Principle #10Preliminary action

3Reliability

If traditional thermosetting resin is replaced with functionalized lignin, then sustainability is improved, but rigidity may deteriorate

Engineering Contradiction:
ImprovesustainabilityVSAvoidrigidity
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent modifies the lignin's chemical parameters through functionalization with alkyne groups, transforming it from a non-cross-linking natural polymer to a thermosetting-capable material. This parameter change introduces reactive sites that enable methylene bridge formation, allowing lignin to achieve rigidity levels comparable to traditional resins while maintaining its sustainable, renewable origin.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite functional structure within the lignin molecule, combining the natural phenolic framework (providing sustainability and basic cross-linking ability) with introduced alkyne functionality (enhancing cross-linking density and rigidity). This molecular composite approach allows lignin to replace traditional thermosetting resins while achieving comparable mechanical performance.

Inventive Principle:
Principle #40Composite materials

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

Achieves better balance between rigidity and hysteresis, ensuring effective BEAD FILLER functionality and resistance to deformation cycles without compromising processability, while offering a sustainable alternative to traditional resins.

Implementation Method 1

a bi-component thermosetting resin, which is made by means of a cross-linking reaction involving methylene bridges

Methodology Applied
Scientific EffectMethylene bridge cross-linking: Chemical Bonding

Implementation Method 2

a vulcanization system... having the purpose of promoting the vulcanization of the polymer base once the compound is subjected to a vulcanization temperature

Methodology Applied
Scientific EffectVulcanization: Chemical Bonding

Data Source

PatentUS11242447B2High rigidity compound for pneumatic tyres comprising functionalized lignin
Publication Date: 2022.02.08 BRIDGESTONE CORP

AI summary

A rubber compound for making a pneumatic tyre structural component comprising a cross-linkable unsaturated-chain polymer base, a reinforcing filler, a thermosetting resin and a vulcanization system. The thermosetting resin comprises functionalized lignin with —OR groups wherein R is an alkyne group with a number of carbon atoms of between (3) and (18).