Polyamide Particle Prepreg for Strength-Toughness Balance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing pre-impregnated composite materials (prepregs) face challenges in maintaining high compression strength and damage tolerance, especially under hot and wet conditions, while also achieving high interlaminar fracture toughness, as increasing compression strength often compromises damage tolerance and vice versa.

Innovation Solution

The use of a matrix resin composed of difunctional and multifunctional epoxy resins, combined with thermoplastic particles made from polyamide 12 (PA12) and polyamide 11 (PA11) particles, along with a curing agent, to create a prepreg that can be molded into composite parts with enhanced strength, damage tolerance, and interlaminar fracture toughness.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If higher modulus resins are selected to increase compression strength, then compression strength is improved, but damage tolerance is reduced

Engineering Contradiction:
Improvecompression strengthVSAvoiddamage tolerance
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The patent applies composite materials by combining epoxy resin with thermoplastic particles (polyamide 12 and polyamide 11) to create a hybrid matrix system. This composite approach allows the epoxy to provide high compression strength while the thermoplastic particles contribute to damage tolerance through their ability to undergo plastic deformation and absorb energy, thus resolving the contradiction between strength and damage tolerance

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent changes the chemical and physical parameters of the resin matrix by incorporating specific ratios of thermoplastic particles (5-20 wt% polyamide 12 and 5-20 wt% polyamide 11). This parameter modification transforms the brittle epoxy matrix into a more ductile composite matrix that maintains high compression strength while significantly improving damage tolerance and compression after impact properties

Inventive Principle:
Principle #35Parameter changes

2Strength

If compression strength is maintained under hot and wet conditions, then compression strength is improved, but interlaminar fracture toughness is reduced

Engineering Contradiction:
Improvecompression strength under hot and wet conditionsVSAvoidinterlaminar fracture toughness
Core Design Contradiction:
StrengthVSStability of the object's composition

Solution Approach 1:

The patent uses composite materials comprising epoxy resin combined with thermoplastic particles (polyamide 12 and polyamide 11) to create a matrix that maintains compression strength under hot and wet conditions while preserving interlaminar fracture toughness. The thermoplastic particles provide a ductile phase that prevents catastrophic crack propagation, thus maintaining both strength and toughness in demanding environmental conditions

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent applies local quality by distributing thermoplastic particles throughout the epoxy matrix to create regions with enhanced local ductility and damage tolerance. This localized modification of material properties allows the composite to maintain high compression strength under hot and wet conditions while preserving interlaminar fracture toughness through the presence of ductile zones that arrest crack propagation

Inventive Principle:
Principle #3Local quality

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

This approach results in composite parts with improved compression strength, damage tolerance, and interlaminar fracture toughness without compromising the physical or chemical characteristics of the uncured prepreg or the cured composite, effectively addressing the limitations of existing prepregs.

Implementation Method 1

the thermoplastic particle component is composed of thermoplastic particles made from polyamide 12 (Nylon 12 or PA12) and thermoplastic particles made from polyamide 11 (Nylon 11 or PA11)

Methodology Applied
Scientific EffectPhase change: Phase Change

Implementation Method 2

a matrix resin composed of difunctional and multifunctional epoxy resins, combined with thermoplastic particles made from polyamide 12 (PA12) and polyamide 11 (PA11) particles, along with a curing agent

Methodology Applied
Scientific EffectChemical bonding: Chemical Bonding

Data Source

PatentUS9187636B2Composite material with polyamide particle mixtures
Publication Date: 2015.11.17 HEXCEL CORP

AI summary

Pre-impregnated composite material (prepreg) is provided that can be cured/molded to form composite parts having high damage tolerance and interlaminar fracture toughness. The matrix resin includes a thermoplastic particle component that includes a mixture of polyamide 12 particles and polyamide 11 particles.