1、Chapter Epoxy Adhesives

two-component package. One-component epoxy adhesives are prepared and supplied by mixing all formulated components in advance including epoxy. resin and curing agent. One-component epoxy adhesives usually need cure at elevated temperature and store at low temperature in a refri.

2、Epoxy Adhesive Formulations

The high catalytic activity of imidazoles and particularly of 2-ethyl-4-methylimidazole (EMI) for the curing of epoxy resins and the properties of the resulting resins prompted this study concerned with the nature of the curing reaction....

3、Preparation and Properties of Epoxy Adhesives with Fast Curing at Room

This work proposes a new method to improve the room-temperature curing speed and low-temperature resistance of epoxy adhesives. Starting from the epoxy resin system, a fast-curing, low temperature-resistant epoxy resin was developed.

Preparation and Properties of Epoxy Adhesives with Fast Curing at Room

ABSTRACT: Developing a highly eficient multifunctional epoxy adhesive is still an enormous challenge, which can rapidly cure at room temperature and has excellent low-temperature resistance performance and is crucial for the epoxy adhesive and electrical sealing fields during severe cold seasons.

Epoxy Curing Agents

Amine curing agent technology for curing polyisocyanate resins. Amicure® IC series of products are specifically designed for use with polyisocyanate resins and other standard HDI trimer based polyisocyanates.

(PDF) Epoxy Adhesives

The printing is performed by a low‐cost Digital Light Processing printer, and the formulation is based on a dual‐cure mechanism, photo, and thermal process.

Curing Agent: Types & Process of Curing Agents for Epoxy Resin

Explore the main types of curing agents & various crosslinking methods which help to improve the polymerization process to select the right curing agent for coating formulation.

Resins and curing agents in epoxy system formulations

For choosing curing agents, there are a few options to consider while formulating an epoxy system, which can help in attaining the desired properties in a wide range of applications.

Formulation of Epoxy Resin Adhesive Curing Agents

Six main classifications of curing agents are commonly utilized with epoxy adhesive formulations, and these can be further divided into several subclassifications.

The epoxy resin system: function and role of curing agents

Depending on their chemical composition, curing agents can be cat-egorised as amine-type curing agents, alkali curing agents, anhydrides, or catalytic curing agents.

In modern industrial and construction fields, epoxy resin is widely utilized for its excellent properties, particularly in bonding, sealing, and protective applications. As a critical component in epoxy resin systems, the performance of epoxy curing agents directly impacts the final product's quality and characteristics. This article introduces the fundamental concepts, types, and interactions of epoxy curing agents with epoxy resin, and explores methods for formulating high-performance epoxy curing agent adhesives.

I. Basic Concepts of Epoxy Curing Agents

Epoxy curing agents are substances that chemically react with epoxy resin, enabling the transition from a liquid to a solid state. They typically contain one or more reactive groups, such as epoxy groups (-C-O-C-) or phenolic hydroxyl groups, which cross-link with the resin's cyclic structure to form a stable three-dimensional network.

II. Types of Epoxy Curing Agents

1. Amine Curing Agents: Include aliphatic amines, aromatic amines, and modified amines. Aliphatic polyamines and aromatic polyamines are most common. These offer good thermal stability and mechanical strength but are costly and produce strong odors.

2. Anhydride Curing Agents: Comprise aliphatic and aromatic anhydrides, such as o-phthalic anhydride and trimellitic anhydride. They provide excellent water and chemical resistance but are expensive and release high levels of volatile organic compounds (VOCs).

3. Imidazoline Curing Agents: Include imidazolines and imidazolones. These are low-toxicity and low-smoke options suitable for eco-sensitive applications.

4. Thioether Curing Agents: Examples include thiodiglycol and thiols. They exhibit low viscosity and good adhesion but poor thermal stability.

5. Specialty Curing Agents: Such as polyamide resins and polyether resins, which have niche applications due to their unique properties.

III. Interactions Between Epoxy Curing Agents and Resin

The interaction between curing agents and epoxy resin occurs through a curing reaction. This exothermic process involves chain growth and cross-linking, forming a robust three-dimensional network. The reactive groups in the curing agent chemically bond with the resin's epoxy rings during this reaction.

IV. Formulating High-Performance Epoxy Adhesives

To develop superior epoxy adhesives, follow these steps:

1. Select Appropriate Epoxy Resin: Choose resin types (e.g., bisphenol A, phenolic, or cycloaliphatic) based on environmental and performance requirements.

2. Determine Curing Agent Type and Dosage: Match the curing agent to the resin’s properties, with dosages typically ranging from 5% to 10% of the resin’s mass.

3. Optimize Resin-to-Curing Agent Ratio: Experiment to find the optimal ratio, considering factors like temperature, humidity, and curing conditions.

4. Ensure Uniform Mixing: Blend the resin and curing agent thoroughly using high-speed mixers to avoid sedimentation or clumping.

5. Add Accelerators and Fillers: Incorporate accelerators to speed up curing and fillers to enhance mechanical strength and wear resistance.

6. Test and Refine: Conduct viscosity, hardness, and tensile tests to evaluate performance. Adjust the formulation based on results to meet target specifications.

Formulating epoxy curing agent adhesives is an interdisciplinary technology spanning materials science, chemical engineering, and practical applications. By selecting suitable resins and curing agents and precisely controlling parameters, high-performance adhesives can be developed for diverse industrial and construction needs. With advances in material science, future innovations will likely introduce more efficient and environmentally friendly epoxy adhesives, further benefiting societal progress.