Acid-Modified Polypropylene Composition for Heat-Resistant Bonding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional adhesives containing acid-modified polyolefin lack sufficient adhesion and heat resistance for bonding low-polarity materials like polypropylene or ABS to metal adherends, necessitating improvements in both properties.

Innovation Solution

A polymer composition comprising unsaturated carboxylic acid-modified polypropylene with specific mass ratios and MFR ranges, produced by reacting polypropylene with unsaturated carboxylic acid and peroxy esters and dialkyl peroxides, is used to enhance adhesion and heat resistance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If acid-modified polyolefin is used as adhesive, then adhesion to low-polarity adherends is improved, but heat resistance is insufficient

Engineering Contradiction:
ImproveadhesionVSAvoidheat resistance
Core Design Contradiction:
StrengthVSTemperature

Solution Approach 1:

The patent changes the chemical parameters of the polyolefin by controlling the degree of acid modification (mass ratio X1-X2 between 0.01-0.5%) and adjusting the MFR (melt flow rate) to specific ranges. These parameter changes enable the adhesive to achieve both good adhesion to low-polarity adherends and improved heat resistance, resolving the contradiction between these two properties.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite adhesive system by combining modified polyolefin with specific amounts of unsaturated carboxylic acid (0.7-1.8% mass ratio) and controlling the graft polymerization degree. This composite approach allows the adhesive to simultaneously achieve adhesion to low-polarity materials and heat resistance that conventional single-component adhesives cannot provide.

Inventive Principle:
Principle #40Composite materials

2Strength

If unsaturated carboxylic acid content is increased to improve adhesion, then adhesion is enhanced, but heat resistance deteriorates

Engineering Contradiction:
ImproveadhesionVSAvoidheat resistance
Core Design Contradiction:
StrengthVSTemperature

Solution Approach 1:

The patent precisely controls the parameter of unsaturated carboxylic acid content within the specific range of 0.7-1.8% mass ratio and controls the graft polymerization degree (mass ratio difference X1-X2 within 0.01-0.5%). This optimized parameter control allows the adhesive to achieve sufficient adhesion while preventing excessive heat resistance deterioration, resolving the contradiction between these opposing requirements.

Inventive Principle:
Principle #35Parameter changes

3Ease of manufacture

If MFR is increased to improve processability, then ease of manufacture is improved, but heat resistance deteriorates

Engineering Contradiction:
ImproveprocessabilityVSAvoidheat resistance
Core Design Contradiction:
Ease of manufactureVSTemperature

Solution Approach 1:

The patent optimizes the MFR parameter to a specific range (1-40 g/10 min at 180°C, 2.16 kg, 1 mm orifice) to balance processability and heat resistance. This controlled parameter adjustment ensures the adhesive is sufficiently processable for practical applications while maintaining adequate heat resistance, resolving the contradiction between ease of manufacture and thermal stability.

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 polymer composition achieves excellent adhesion and heat resistance, suitable for bonding low-polarity materials to metal, with controlled unsaturated carboxylic acid content and MFR, ensuring stability and performance.

Implementation Method 1

an adhesive having excellent adhesion and heat resistance

Methodology Applied
Scientific EffectAdhesion: Adhesive

Implementation Method 2

an adhesive having excellent adhesion and heat resistance

Methodology Applied
Scientific EffectThermal stability:

Data Source

PatentUS20250223433A1Polymer composition, method for producing polymer composition, and aqueous dispersion composition
Publication Date: 2025.07.10 MCPP INNOVATION LLC

AI summary

A polymer composition comprising a modified polypropylene modified with at least one selected from the group consisting of an unsaturated carboxylic acid and a derivative thereof.