Epoxy Curing Agent Segmentation for Fast Cure and Long Pot Life
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Epoxy resin compositions used in high-cycle RTM processes lack optimal properties such as low viscosity, fast curing, long pot life, and high glass transition temperature (Tg) of the cured product, which are crucial for high productivity and efficient molding of fiber-reinforced composite materials.
Innovation Solution
An epoxy resin curing agent comprising N-aminoethylpiperazine and/or isophoronediamine, combined with norbornanediamine, in specific mass ratios, to achieve low viscosity, fast curing, and improved Tg of the cured product.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If fast curing epoxy resin composition is used, then curing speed is improved, but pot life becomes short causing premature curing before molding
Solution Approach 1:
The curing agent is segmented into two distinct components: Component A (polyfunctional amine compound with long pot life) and Component B (curing accelerator with fast curing capability). By separating the functions of pot life extension and curing acceleration into different components, the system achieves both long pot life and fast curing without premature curing before molding.
Solution Approach 2:
The invention uses a composite curing agent system combining Component A and Component B in specific ratios (0.2-2.0 parts B per 1 part A by mass). This composite approach leverages the complementary properties of both components: Component A provides long pot life and Component B provides fast curing, achieving synergistic effects that neither component could achieve alone.
2Speed
If low viscosity epoxy resin composition is used, then mold filling speed is improved, but curing control becomes difficult leading to premature curing
Solution Approach 1:
The curing agent is segmented into Component A (polyfunctional amine compound providing stability and long pot life) and Component B (curing accelerator providing fast reactivity). This segmentation allows the low-viscosity composition to fill molds quickly while Component A maintains curing control stability, preventing premature curing despite the low viscosity.
Solution Approach 2:
The invention optimizes the mass ratio parameters of Components A and B (0.2-2.0 parts B per 1 part A) to achieve the desired balance between low viscosity for fast mold filling and controlled curing stability. This parameter optimization ensures that the composition remains stable during handling and injection while curing rapidly after mold closure.
3Temperature
If high glass transition temperature (Tg) is achieved, then heat resistance is improved, but viscosity of the composition increases reducing processability
Solution Approach 1:
The curing agent is divided into Component A (polyfunctional amine compound that contributes to high Tg and heat resistance) and Component B (curing accelerator that maintains low viscosity). This segmentation allows the system to achieve high Tg values (100°C or higher) while Component B ensures the composition remains low-viscosity and processable during handling and injection.
Solution Approach 2:
The composite curing agent system combines Component A and Component B in optimized ratios to achieve synergistic effects: Component A provides the molecular structure necessary for high Tg and heat resistance, while Component B maintains low viscosity for excellent processability. This composite approach achieves both high performance and ease of processing simultaneously.
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 solution enables high productivity in producing CFRP for automotive and building materials by ensuring fast curing, low viscosity, and high Tg, thereby reducing molding time and improving the mechanical properties of the composite materials.
Implementation Method 1
an epoxy resin curing agent comprising (A) at least one compound selected from the group consisting of N-aminoethylpiperazine and isophoronediamine
Implementation Method 2
the epoxy resin is cured to perform molding
Data Source
AI summary
An epoxy resin curing agent including: (A) at least one compound selected from the group consisting of N-aminoethylpiperazine and isophoronediamine, and (B) norbornanediamine, an epoxy resin composition including the same, a fiber-reinforced composite material including the cured product of the epoxy resin composition and a reinforcing fiber.