APCHA Curing Agent for Wind Turbine Adhesive Pot Life
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current adhesives used for bonding wind turbine blade halves lack sufficient pot life, are sensitive to long open times, and do not maintain bonding strength under varying environmental conditions, particularly with the increasing size of wind turbine blades.
Innovation Solution
An adhesive composition comprising a reaction product of an epoxy resin component and an amine-based curing agent formulation, specifically using N-(3-aminopropyl)cyclohexylamine (APCHA) along with polyamide, cycloaliphatic amine, polyether diamine, and ether diamine, which provides improved viscosity, reactivity, and thermal performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If epoxy-based adhesives are used to bond wind turbine blade shells, then bond strength is achieved, but pot life is insufficient and the adhesive is sensitive to long open times
Solution Approach 1:
The patent changes the chemical parameters of the curing agent by using a multi-component amine formulation containing APCHA (N-(3-aminopropyl)cyclohexylamine) combined with polyamide, cycloaliphatic amine, polyether diamine, and ether diamine. This composition modification extends pot life while maintaining bond strength by controlling the curing kinetics and reactivity of the adhesive system.
Solution Approach 2:
The patent employs a composite curing agent system combining multiple amine components (APCHA, polyamide, cycloaliphatic amine, polyether diamine, ether diamine) in specific weight ratios. This composite approach synergistically extends pot life and improves open time performance while preserving the adhesive's bonding capability under various environmental conditions.
2Strength
If epoxy-based adhesives are used for bonding, then initial bond strength is achieved, but bonding capability deteriorates after long open times
Solution Approach 1:
The patent modifies the chemical composition parameters of the curing agent to include APCHA (5-50 wt%), polyamide (30-60 wt%), cycloaliphatic amine (10-30 wt%), polyether diamine (10-30 wt%), and ether diamine (5-20 wt%). This parameter optimization maintains adhesive reactivity and bonding capability even after extended open times under adverse environmental conditions.
Solution Approach 2:
The multi-component amine formulation acts as an intermediary system that mediates between the epoxy resin and the substrate, providing controlled reactivity and extended working time. The combination of different amine components creates a balanced curing profile that preserves bonding capability during extended open periods.
3Speed
If adhesive reacts quickly, then bond strength develops rapidly, but pot life becomes too short for practical application
Solution Approach 1:
The patent optimizes the reaction kinetics parameters by selecting a multi-component amine curing system with different reactivity rates. APCHA provides initial reactivity for rapid bond development, while the other amine components (polyamide, cycloaliphatic amine, polyether diamine, ether diamine) contribute to extended pot life through slower curing reactions, achieving a balanced cure profile.
Solution Approach 2:
The patent creates a dynamic curing process where the multi-component amine formulation provides different reaction rates at different stages. The system transitions from rapid initial bonding to slower extended curing, allowing practitioners to work with the adhesive for extended periods while still achieving rapid initial strength development.
4Reliability
If adhesive is sensitive to environmental conditions, then bonding performance varies under different conditions, but robustness over wide temperature and humidity ranges is needed
Solution Approach 1:
The patent uses a composite amine curing system where each component contributes different properties: APCHA provides good adhesive performance and thermal stability, polyamide offers flexibility and moisture resistance, cycloaliphatic amine contributes to chemical resistance, polyether diamine provides low-temperature flexibility, and ether diamine enhances overall durability. This composite approach ensures reliable bonding performance across wide temperature and humidity ranges.
Solution Approach 2:
The patent optimizes the weight ratio parameters of the amine components to achieve environmental robustness. The specific formulation ranges (APCHA: 5-50%, polyamide: 30-60%, cycloaliphatic amine: 10-30%, polyether diamine: 10-30%, ether diamine: 5-20%) are designed to balance reactivity, flexibility, and environmental resistance, ensuring consistent bonding performance under varying environmental conditions.
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 adhesive composition demonstrates enhanced bonding strength and stability even after extended open times, with a significant reduction in performance drop under adverse conditions, effectively addressing the limitations of prior art adhesives.
Implementation Method 1
The adhesives that are utilized to couple the wind turbine blade halves must be able to withstand the centrifugal forces applied to each blade during use and maintain bond strength for the blade's lifetime
Implementation Method 2
The term 'pot life', as those of ordinary skill in the adhesives arts recognizes, may be defined as the time period in which the adhesive composition is sufficiently liquid such that it may be applied to a substrate material to be bonded
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to structural adhesive compositions and more particularly to two-component (2K) structural adhesive compositions. The two components chemically react to bond structural surfaces. N-(3-Aminopropyl)cyclohexylamine (APCHA) has been found to be an improved curing agent for use with epoxy resins in 2K adhesive compositions. APHCA exhibits favorable features including viscosity, pot life and reactivity, and adhesive and thermal performance after curing with epoxy resin. These features and its unique chemistry allow the use of APCHA in curing agent formulations for structural adhesives, in particular wind turbine blade adhesives. APCHA solves issues with viscosity build-up, working time, through-cure, compatibility and adhesive performance that cannot be addressed with the commonly used amine formulations.