Kinetic Study and New Applications of UV Radiation Curing

TLDR

Highly crosslinked polymers can be synthesized by photoinitiated polymerization of multifunctional monomers or functionalized polymers. UV irradiation with radical and cationic photoinitiators, monitored by real‑time IR spectroscopy, enables rapid synthesis of interpenetrating polymer networks and crosslinking of solid polymers bearing acrylate, vinyl, or epoxy groups at ambient temperature. UV curing of acrylate resins yields long kinetic chains despite high initiation rates, and RT‑IR analysis reveals how initiation efficiency, oligomer structure, light intensity, and oxygen inhibition affect polymerization, while the technique produces weather‑resistant coatings, high‑resolution images, glass laminates, and nanocomposites within seconds. Image shows photoinitiated crosslinking polymerization.

Abstract

Abstract Highly crosslinked polymers can be readily synthesized by photoinitiated polymerization of multifunctional monomers or functionalized polymers. The reaction can be followed in situ by real‐time infrared (RT‐IR) spectroscopy, a technique that records conversion versus time curves in photosensitive resins undergoing ultrafast polymerization upon UV exposure. For acrylate‐based resins, UV‐curing proceeds with long kinetic chains (7700 mol/radical) in spite of the high initiation rate. RT‐IR spectroscopy proved very valuable in assessing the influence of various parameters, such as initiation efficiency, chemical structure of the telechelic oligomer, light intensity, inhibitory effect of oxygen, on polymerization kinetics. Interpenetrating polymer networks can be rapidly synthesized by means of UV irradiation of a mixture of difunctional acrylate and epoxy monomers in the presence of both radical and cationic‐type photoinitiators. The same UV technology can be applied to crosslink solid polymers at ambient temperature, which bear different types of reactive groups (acrylate and vinyl double bonds, epoxy ring). UV radiation curing has been successfully used to produce within seconds weathering resistant protective coatings, high‐resolution relief images, glass laminates and nanocomposites materials. Photoinitiated crosslinking polymerization. magnified image Photoinitiated crosslinking polymerization.