1、Curing reactions of epoxy powder coatings in perspectives of chemical
The properties of the cured products of epoxy powder coatings are dominated by the curing systems. This review discusses the types, reaction principles, characteristics of curing agents and accelerators that participate in the curing reaction with different epoxy resins.
2、The epoxy resin system: function and role of curing agents
In the presence of curing agents, epoxy resins become rigid and infusible. Eco-friendliness and mechanical functionality have emerged as vulcanization properties.
3、Effect of Curing Agent Type on Curing Reaction Kinetics of Epoxy Resin
In this paper, low molecular weight polyamides, aromatic amines and anhydrides were selected as three kinds of curing agents and their isothermal viscosity-time properties were studied to...
4、A REVIEW ON DEVELOPMENTS IN CURING AGENTS FOR EPOXY RESINS
The cured epoxy resin itself is generally brittle in nature and to convert the epoxy resins to hard, fusible thermoset network, it is necessary to use chemical curing agents.
Epoxy Curing Agents
This chapter focuses on epoxy curing agents, also known as curatives, which include crosslinkers and catalysts.
Interactions and Curing Dynamics Between UV
The epoxy acrylate and curing agent were mixed in an equivalent ratio of 1:1 to ensure optimal curing. A photoinitiator was added at a concentration of 1 phr relative to the total amount of epoxy resin, as shown in Table 1.
Curing reaction of epoxy resin composed of mixed base resin and curing
In the curing experiment of epoxy resin, we used differential scanning calorimetry (DSC) to obtain the conversion by mixing curing agents and base resins.
Influence of different composite curing agents on the rapid curing
In particular, effective formulations are designed for mixing fast and slow curing agents, studying their effects on the curing behavior, curing quality, and mechanical properties of epoxy resins and elucidating their influence mechanisms.
Effect of curing conversion on the water sorption, corrosion resistance
In this work, we selected one of the most well-used epoxy systems, the diglycidyl ether of bisphenol A/diaminodiphenyl-sulfone (DGEBA/DDS), as the model to study the relationship between curing conversion and thermo-mechanical, water sorption, and corrosion resistance properties.
Curing agents for epoxy resins
In order to convert epoxy resins to hard, infusible thermoset networks it is necessary to use crosslinking agents. These crosslinkers , hardeners or curing agents as they are widely known, promote cross-linking or curing of epoxy resins.
Epoxy resin, a thermosetting plastic with high cross-linking density, is widely used in aerospace, automotive, construction, and electronics due to its exceptional performance. Its properties largely depend on the curing process, where curing agents play an indispensable role as chemical facilitators. In both the manufacture and application of epoxy resins, curing agents are critical determinants of the final product’s quality.
Epoxy curing agents come in diverse categories, classified by chemical structure into aliphatic, aromatic, and heterocyclic types. Each type has unique characteristics and suitability for specific applications, making the selection of the appropriate curing agent essential for optimizing epoxy product performance.
Aliphatic Curing Agents are among the most commonly used. They typically contain long-chain alkyl or aryl groups, offering excellent adhesive strength and mechanical properties. These agents react with epoxy at room temperature, forming a three-dimensional network structure that imparts superior temperature resistance and chemical stability. For example, dimethylbenzylamine (DMBA) is a widely used aliphatic curing agent that enables rapid curing at low temperatures.
Aromatic Curing Agents are characterized by fast reaction rates but relatively lower thermal and chemical resistance. certain aromatic agents like m-phenylenediamine (MPD) facilitate quick curing at low temperatures while delivering robust mechanical properties. These are valuable for applications requiring rapid setting, such as electronic encapsulants and high-performance composites.
Heterocyclic Curing Agents stand out for their unique structures and properties. Containing multiple heteroatoms (e.g., nitrogen, oxygen, or sulfur), they enhance chemical stability and mechanical performance. These agents excel in high-temperature environments and are frequently used in aerospace and nuclear energy applications for advanced epoxy products.
The selection of epoxy curing agents must balance chemical properties, cost, environmental impact, and processability. With stricter environmental regulations, developing low-VOC and low-toxicity curing agents has become a industry priority. Additionally, innovations in multifunctional curing agents are emerging to address complex industrial demands.
The conversion of epoxy curing agents involves scientific challenges related to reaction equilibrium constants, kinetics, and temperature control. Engineers adjust curing agent ratios based on specific processing conditions and product requirements. For instance, achieving optimal adhesive strength may require precise temperature-controlled adjustments to the curing agent dosage.
During the curing process, curing agents first react with hydroxyl groups in epoxy resins, forming solvent-insoluble networks. This exothermic reaction accelerates at higher temperatures, necessitating careful temperature management to regulate reaction rates and ensure desired outcomes.
The science and application of epoxy curing agents remain dynamic fields. Ongoing advancements promise more efficient, eco-friendly curing agents to meet modern industries’ demands for high-performance, reliable epoxy products. These innovations will drive progress in materials science and manufacturing, enabling breakthroughs across diverse sectors.
