Polyamide Composite Thermal Aging Resistance via PEI Surface Layer

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Fiber-reinforced plastic composite components lack satisfactory thermal aging resistance, which affects their mechanical properties and longevity when exposed to elevated temperatures, despite previous attempts to improve thermal aging stability using copper-based stabilizers and polyhydric alcohols.

Innovation Solution

A plastic composite component comprising a polyamide matrix polymer reinforced with fibers, where the surface composition includes polyethyleneimine (PEI) to enhance thermal aging resistance, while the matrix composition does not necessarily contain PEI, allowing for cost-effective production and improved adhesion between components.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If copper-based stabilizers and polyhydric alcohols are used to improve thermal aging stability, then thermal aging resistance is improved, but production cost increases and adhesion between components deteriorates

Engineering Contradiction:
Improvethermal aging resistanceVSAvoidproduction cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent removes copper-based stabilizers and polyhydric alcohols from the composition entirely, replacing them with polyethyleneimine (PEI) as a single alternative additive. This extraction of harmful or costly substances while maintaining the thermal aging protection function resolves the contradiction between reliability and manufacturing ease.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent changes the chemical parameter of the thermal stabilizer from copper-based compounds to polyethyleneimine, fundamentally altering the chemical composition to achieve both cost reduction and improved adhesion while maintaining thermal aging resistance. This parameter change enables a single substance to fulfill multiple functions.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If PEI is added to both surface composition and matrix composition, then thermal aging resistance is maximized, but production cost increases

Engineering Contradiction:
Improvethermal aging resistanceVSAvoidPEI content
Core Design Contradiction:
ReliabilityVSQuantity of substance

Solution Approach 1:

The patent applies PEI selectively only to the surface composition rather than uniformly throughout the entire composite material. This localized application provides thermal aging protection where it is most needed (at the surface exposed to environmental conditions) while reducing the overall quantity of PEI required, thereby lowering production costs.

Inventive Principle:
Principle #3Local quality

3Strength

If fiber-reinforced plastics are used to reduce weight and cost, then mechanical properties improve, but thermal aging resistance deteriorates

Engineering Contradiction:
Improvemechanical propertiesVSAvoidthermal aging resistance
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The patent creates a composite formulation by combining fiber-reinforced plastic with polyethyleneimine in the surface composition. This composite approach allows the material to simultaneously achieve good mechanical properties from the fiber reinforcement and improved thermal aging resistance from the PEI additive, resolving the contradiction between these two performance aspects.

Inventive Principle:
Principle #40Composite materials

Data Source

PatentUS10030110B2Composite plastic part with improved resistance to heat aging
Publication Date: 2018.07.24 BASF SE

AI summary

The present invention relates to a process for producing a plastic composite component (CC) in which a first fiber material (F1) is impregnated with a polyamide matrix polymer (PAM) to obtain a matrix composition (MC), to which a surface composition (SC) is applied, and a first plastic component (C1) is obtained. In a second step, a second plastic component (C2) is molded onto the first plastic component (C1), giving the plastic composite component (CC). The invention further relates to the plastic composite component (CC) obtainable by the process of the invention. The present invention further provides for the use of polyethyleneimine (PEI) for improving the impregnation of the first fiber material (F1) with the polyamide matrix polymer (PAM).