We begin this new year with a continuation of the discussion of microgels, i.e., “nanogels,” introduced in the previous issue of UV+EB Technology.1 Recall from that previous discussion that in UV/EB polymerization processes, particularly those involving free radical addition polymerization of (meth)acrylate-functional monomers and oligomers, a large number of amorphous nanogels … [Read more...] about Special Topic: Microgels – Part 2
Photopolymerization
Photopolymerization of Methylene Malonates
By J. Taylor Goodrich, Alexander Y. Polykarpov and Anushree Deshpande, Sirrus, Inc. Introduction It could be said that the modern era of commercial photopolymerization began in 1964 with the installation of the first electron beam cure unit at Boise Cascade for wood finishing. Fifty-five years later, the field of photopolymerization continues to expand: A simple search on … [Read more...] about Photopolymerization of Methylene Malonates
Special Topic: Microgels – Part 1
The first seven editions of “Professor’s Corner” focused on the fundamentals of polymer chemistry as they apply to the field of UV/EB polymerization. In this eighth edition, a special topic is introduced. It is probably not well known that a typical UV/EB polymerization process produces films that contain vast numbers of particles or domains or phases known as “microgels.” This … [Read more...] about Special Topic: Microgels – Part 1
Counting Radicals: Methods to Measure Radiation Yields of Monomers in EB Polymerization
By Nicole L. K. Thiher and Julie L. P. Jessop, University of Iowa, and Sage M. Schissel, PCT Ebeam and Integration, LLC Introduction For photopolymerization, many methods exist to determine kinetic parameters, such as quantum yield of photoinitiators and rate of photoinitiation. However, due to the harsh conditions of the electron beam, relatively few studies have examined … [Read more...] about Counting Radicals: Methods to Measure Radiation Yields of Monomers in EB Polymerization
Photopolymerization Fundamentals Event Convenes in Colorado
By Darryl Boyd, US Naval Research Laboratory, and Mike Idacavage, Colorado Photopolymer Solutions The Photopolymerization Fundamentals Meeting convened September 17 through 20 in scenic Boulder, Colorado, at the elegant St. Julien Hotel & Spa. The biennial occasion once again began with a series of Short Courses that were taught by leaders from various focus areas … [Read more...] about Photopolymerization Fundamentals Event Convenes in Colorado