14.1 INTRODUCTION

This chapter considers epoxy adhesive formulations that are rather unconventional. These include

• Epoxy adhesives that cure via radiation (ultraviolet light or electron beam energy)

• Epoxy adhesives that are available as waterborne emulsions

• Epoxy adhesives that cure via indirect thermal means (induction, dielectric, microwave, and several others)

These adhesives have found their way into several niche markets where their advantages, such as fast setting speed, are highly valued. They have not seen application in the more ordinary markets because of their materials and equipment cost. However, it is expected that these epoxy adhesive systems will grow at a faster annual rate than the average market as their advantages become more widely known.

14.2 ULTRAVIOLET AND ELECTRON BEAM CURED EPOXY ADHESIVES

Radiation curing is a production technique for polymerizing and curing of adhesives through the use of radiant energy. The source of the radiant energy is generally electron beam (EB), ultraviolet (uv) light, or visible light. These forms of radiation have the energy necessary to initiate polymerization of low-molecular-weight, unsaturated resins including various types of epoxy resins.

Polymeric inks, coatings, adhesives, or similar products can be cured with radiant energy. Examples of adhesive applications include

• Laminating and packaging adhesives

• Bonding of woven and nonwoven textiles

• Fastening (tacking and fixturing), potting, and encapsulation of electrical and electronic components

• Vehicle assembly (aerospace, automotive, recreational, mobile home, etc.)

• Glass-to-metal and glass-to-glass bonding, and jewelry assembly

• Optical-fiber connector bonding

• Plastic component bonding

• The assembly of medical components and consumer products

One of the most...