Microcapsule Latent Curing Agent for Epoxy Resins
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional aluminum chelate-based latent curing agents for thermosetting epoxy resins require high temperatures for curing and have a broad exothermic peak, limiting their latency and thermal response.
Innovation Solution
A microcapsule-type latent curing agent is developed by retaining an aluminum chelating agent in a porous resin obtained through interfacial polymerization of a polyfunctional isocyanate compound, with an enzyme-treated gelatin film coating, which shifts the exothermic onset temperature to higher values and narrows the temperature width of the exothermic peak, enhancing latency and thermal response.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If conventional aluminum chelate-based latent curing agents are used, then low-temperature curing activity is achieved, but the exothermic peak temperature is too low and the temperature width is too broad, resulting in poor latency and thermal response
Solution Approach 1:
The patent embeds the aluminum chelating agent within a porous resin bead structure, creating a nested configuration where the curing agent is contained within the porous matrix. This nesting approach concentrates the curing activity within a confined spatial structure, thereby narrowing the exothermic peak temperature width while maintaining low-temperature curing capability, thus improving both latency and thermal response
Solution Approach 2:
The patent creates a composite material system combining aluminum chelating agent, porous resin bead, and shell material. This composite structure allows the aluminum chelating agent to be distributed and contained within the porous resin matrix, which concentrates and narrows the exothermic peak temperature profile while preserving the low-temperature curing activity, thereby resolving the contradiction between temperature control and curing effectiveness
2Reliability
If the exothermic peak temperature is shifted to higher temperatures, then latency is improved, but the temperature width increases and peak intensity decreases, worsening thermal response
Solution Approach 1:
By nesting the aluminum chelating agent within the porous resin bead structure, the patent achieves a concentrated distribution of curing agents that narrows the exothermic peak temperature width. This nested configuration allows the exothermic peak to occur at higher temperatures (improving latency) while maintaining a sharp, narrow profile (preserving thermal response), thus resolving the contradiction between latency improvement and thermal response degradation
3Productivity
If aluminum chelating agent is retained in porous resin obtained by interfacial polymerization, then low-temperature rapid curability is achieved, but storage stability is insufficient
Solution Approach 1:
The patent nests the aluminum chelating agent within the porous resin bead, which is then enclosed by a protective shell material. This double-nesting structure (agent within bead, bead within shell) provides physical containment that prevents premature reaction during storage (improving storage stability) while enabling rapid curing when activated (maintaining low-temperature rapid curability)
Solution Approach 2:
The patent employs a shell material that forms a protective barrier around the porous resin bead containing the aluminum chelating agent. This shell acts as a flexible containment structure that prevents premature contact between the curing agent and epoxy resin during storage (improving storage stability) while allowing controlled release during curing (maintaining rapid curability)
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 microcapsule-type latent curing agent enables low-temperature, rapid curing of thermosetting epoxy resins with improved storage stability and thermal response, allowing for controlled curing conditions and efficient low-temperature rapid curability.
Implementation Method 1
an enzyme-treated gelatin film coating the latent curing agent
Implementation Method 2
a porous resin obtained by interfacial polymerization of a polyfunctional isocyanate compound
Implementation Method 3
an aluminum chelating agent is retained in a porous resin
Data Source
AI summary
An aluminum chelate-based latent curing agent having excellent latency and thermal response includes a latent curing agent in which an aluminum chelating agent is retained in a porous resin obtained by interfacial polymerization of a polyfunctional isocyanate compound, and an enzyme-treated gelatin film coating such latent curing agent. This microcapsule-type latent curing agent can be produced by dissolving an aluminum chelating agent and a polyfunctional isocyanate compound in a volatile organic solvent, charging the obtained solution into a gelatin-containing aqueous phase, carrying out interfacial polymerization by heating and stirring, and subjecting the gelatin to an enzyme treatment by adding an enzyme to the obtained polymerization reaction mixture.