1、Latent curing epoxy systems with reduced curing temperature and
Unlike multicomponent epoxy systems, curing agents used in single component epoxy adhesives are usually latent curing agents, such as dicyandiamide, organic hydrazine, and imidazole [[8], [9], [10], [11]].
2、Novel Thermal Latent Curing Agents for Epoxy Resins Based on Dual
Herein, we present a dual-locked thermal latent curing agent based on aminopyridines, protected by amidation and N -oxidation, designed to enhance both pot life and final curing efficiency.
3、Research Progress of Latent Curing Agent for Epoxy Resin
According to the chemical structure, latent curing agents include dicyandiamide, hydrazide, anhydride, benzoxazine and amino acid compounds, imidazole and modified amine compounds, boron amine complex and diazonium salt, iodonium salt and sulfonium salt compounds.
4、Epoxy Curing Agents – Latent Curing Agents for One Component Systems
Latent curing agents are clearly the choice for one component heat activated epoxy systems. Latency is achieved through either physical insolubility or lack of chemical reactivity at room temperature, and the reactivity, solubility, and latency all must be carefully balanced.
Thermal curing of epoxy resins at lower temperature using 4
In this study, we present N -methyl- N -pyridyl amide derivatives as thermal latent curing agents for use at lower temperatures, along with their mechanism of epoxy curing through the generation of the highly reactive 4- (methylamino)pyridine (4MAPy) (Figure 1).
LATENT CURING AGENTS AND ACCELERATORS FOR EPOXY RESIN AJICURE
Ajicure PN-23J is the fastest curing agent of all Ajicures. However Ajicure PN-23J is so fine particle that its pot life formulated with epoxy resins is relatively short.
The epoxy resin system: function and role of curing agents
Depending on their chemical composition, curing agents can be categorised as amine-type curing agents, alkali curing agents, anhydrides, or catalytic curing agents.
Preparation of Latent Curing Agent for Epoxy Resin by Encapsulation
The microcapsule-type curing agents DDM-PMMA and IZ-PU were prepared by solvent evaporation method and interfacial polymerization method, respectively. The surface morphology of the two microcapsules was characterized by SEM.
Advanced Latent Curing Agents for Epoxy Resin Systems: Enhanced Control
Discover innovative latent curing agents for epoxy resins offering superior storage stability, precise curing control, and enhanced performance characteristics.
Several Kinds of Commonly Used Epoxy Resin Curing Agents
The number of epoxy resin curing agents is divided into the explicit curing agent and the latent curing agent. Here are some types of curing agents.
In modern industrial and construction fields, epoxy materials are widely utilized due to their excellent mechanical properties, chemical stability, and electrical insulation characteristics. As a core component of epoxy systems, the diversity of latent curing agents directly impacts the final performance and application scope of epoxy materials. This article aims to explore different types of latent curing agents for epoxy systems and their characteristics, providing comprehensive reference information for engineers and technical personnel.
Epoxy resin is a thermosetting polymer formed by the condensation of polybasic acids and polyamines. It is extensively used in coatings, adhesives, composite materials, and other fields. In epoxy systems, latent curing agents promote the curing reaction of the resin and enhance the performance of the cured product. Based on curing mechanisms, latent curing agents can be classified into free radical-initiated, cationic-initiated, and anionic-initiated types.
1. Free Radical-Initiated Curing Agents
These primarily include benzoyl peroxide (BPO), t-butyl peroxide (TBPO), and similar compounds. They initiate the polymerization and cross-linking of epoxy resins by releasing free radicals. The advantages of such curing agents include fast reaction speeds and low curing temperatures. their drawbacks lie in environmental pollution caused by free radicals and potential degradation of mechanical properties when used in excess.
2. Cationic-Initiated Curing Agents
This group includes imidazole compounds (e.g., N-methylimidazole [NMIM]) and quaternary ammonium salts (e.g., triethylamine). They trigger epoxy polymerization by accepting electrons, often requiring catalysts to accelerate curing. Cationic-initiated curing agents are suitable for waterborne systems and yield cured materials with good electrical insulation and hydrophobicity. they necessitate catalyst addition and may generate harmful gases under certain conditions.
3. Anionic-Initiated Curing Agents
Examples include persulfates (e.g., sodium persulfate [Na₂S₂O₈]), organic peroxides (e.g., benzoyl peroxide), and combinations of persulfates and organic peroxides. These agents initiate polymerization and cross-linking by releasing anions. Their strengths include compatibility with diverse epoxy systems and low curing temperatures. their use is limited due to potential environmental and health hazards associated with released anions.
4. Specialty Latent Curing Agents
Beyond the above categories, specialized curing agents such as rare earth compounds and metal-organic frameworks (MOFs) exist. These materials offer unique physical or chemical properties tailored to specific application needs.
Key Considerations for Selecting Latent Curing Agents
Engineers and technicians must evaluate multiple factors when choosing latent curing agents:
- Compatibility: Match the curing agent to the epoxy type and application scenario.
- Environmental and Safety: Prioritize eco-friendly options, especially for food, pharmaceutical, or medical applications.
- Cost: Balance performance and economic efficiency.
- Additive Compatibility: Ensure compatibility with fillers, pigments, leveling agents, etc., and verify post-curing physical/chemical properties.
The variety of latent curing agents for epoxy systems reflects distinct advantages, limitations, and application contexts. Proper selection and usage are critical for developing high-performance, eco-friendly, and cost-effective epoxy materials. With advancements in material science, future innovations in latent curing agents are expected to address increasingly stringent industrial and construction demands.
