Hydrogenated Block Copolymer Softening Modifiers

Solution Overview

Problem

Conventional block copolymers face a trade-off between increased softness and processability, as additives like plasticizing oils enhance these properties but often compromise temperature resistance and strength, while high molecular weight low polydispersity index homopolymers can lead to oil bleed-out at elevated temperatures.

Innovation Solution

The development of novel block copolymer compositions combining selectively hydrogenated block copolymers with tailored softening modifiers, where the softening modifier is made 'in-situ' with the block copolymer, maintaining strength and upper service temperature performance while improving softness and processability without significant reductions in properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If plasticizing oils are added to block copolymers to increase softness and improve processability, then softness and processability are improved, but temperature resistance and strength are reduced

Engineering Contradiction:

ImproveprocessabilityVSAvoidtemperature resistance

Core Design Contradiction:

Ease of operationVSTemperature

Solution Approach 1:

The invention changes the chemical structure parameters of the polymer by selectively hydrogenating the diene block while leaving the arene block untouched. This creates a modified polymer with altered physical properties that provides softness without the negative effects of traditional plasticizing oils. The hydrogenation degree is controlled to achieve optimal balance between softness and temperature resistance.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention creates a composite material system by combining the hydrogenated diene block with the non-hydrogenated arene block in a block copolymer structure. This composite approach allows each block to contribute its advantageous properties: the hydrogenated diene provides softness and flexibility, while the arene block maintains strength and temperature resistance.

Inventive Principle:

Principle #40Composite materials

2Ease of operation

If plasticizing oils are added to block copolymers to increase softness and improve processability, then softness and processability are improved, but strength is reduced

Engineering Contradiction:

ImproveprocessabilityVSAvoidstrength

Core Design Contradiction:

Ease of operationVSStrength

Solution Approach 1:

The invention changes the chemical structure parameters of the polymer by selectively hydrogenating the diene block while leaving the arene block untouched. This creates a modified polymer with altered physical properties that provides softness without the negative effects of traditional plasticizing oils. The hydrogenation degree is controlled to achieve optimal balance between softness and temperature resistance.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention creates a composite material system by combining the hydrogenated diene block with the non-hydrogenated arene block in a block copolymer structure. This composite approach allows each block to contribute its advantageous properties: the hydrogenated diene provides softness and flexibility, while the arene block maintains strength and temperature resistance.

Inventive Principle:

Principle #40Composite materials

3Reliability

If high molecular weight low polydispersity index homopolymers are blended to improve properties, then certain properties are improved, but oil bleed out occurs at elevated temperatures

Engineering Contradiction:

Improveproperty improvementVSAvoidoil bleed out

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The invention changes the chemical structure parameters by selectively hydrogenating the diene block, which alters the molecular interactions and prevents oil bleed-out. The hydrogenation creates a more stable polymer structure that maintains its properties at elevated temperatures without releasing oil or volatile components.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention replaces traditional plasticizing oils with a polymer-modified structure that provides similar softness benefits without the harmful side effects. The modified polymer acts as its own softening agent, eliminating the need for separate plasticizing components that can bleed out.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

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 compositions achieve improved upper service temperature performance, strength, and reduced volatility with enhanced organoleptic properties and lower extractable levels, along with significant process advantages, such as reduced fogging and no smoke in film and fiber applications.

Implementation Method 1

selectively hydrogenated block copolymers of mono alkenyl arenes and conjugated dienes

Methodology Applied

Scientific EffectSelective hydrogenation: Hydrogenation

Implementation Method 2

blending in various other polymers

Methodology Applied

Scientific EffectPolymer blending:

Data Source

PatentUS7592390B2Hydrogenated block copolymer compositions

Publication Date: 2009.09.22 KRATON POLYMERS US LLC

AI summary

The present invention relates to novel compositions comprising (a) anionic block copolymers of mono alkenyl arenes and conjugated dienes, and (b) tailored softening modifiers have a particular polydispersity index that results in a surprising improvement in properties for the composition. Also included are processes for the manufacturing such novel compositions and various end-uses and applications for such compositions.