Preparation of UV‐thermal dual curable environmentally friendly polyacrylate pressure‐sensitive adhesives by bulk polymerization

Abstract

Three different acrylate monomers containing butyl acrylate, 2‐hydroxyethyl acrylate, and acrylic acid were designed to synthesize polyacrylate pressure‐sensitive adhesives (PSAs) by bulk polymerization process initiated via radical photo‐initiators under UV irradiation and UV‐thermal dual curing. Thermal crosslinker, KL‐1202, with trifunctional isocyanate groups was introduced into the prepolymer to form an intermolecular crosslinking network structure. An emphasis was placed on the effect of the KL‐1202 content on the microstructure and adhesive properties of PSAs. The viscosity and composition of prepolymer synthesized by UV initiation were tested by a rotational viscometer and Fourier transform infrared spectroscopy, respectively. The degree of crosslinking of the final PSA was evaluated by the gel content value obtained via Soxhlet extraction, while the molecular weights of the soluble parts of PSA polymers were measured by gel permeation chromatography. Dynamic mechanical analysis was used to characterize the viscoelastic performance of PSAs. Moreover, the adhesive properties of PSAs were determined through a series of tests including loop tack force, peel force, and shear resistance. It was found that the C=C double bond and the isocyanate group disappeared after UV radiation and thermal curing process. Dual‐cure acrylate PSAs compensate for limitations in UV‐induced cure of thick coatings. The Tg value, storage modulus (G′), and shear resistance of PSAs were improved while the loop tack force and peel force of PSAs decreased as the KL‐1202 content increased.

Preparation and UV‐curing properties of rosin‐based allyl phthalate oligomer

“…Due to environmental problems and the depletion of petroleum resources, the application research of environmental protection technology and renewable resources has attracted widespread attention in recent years 1–23 . UV‐curing technology has a wide range of applications in adhesives, 4,5 coatings, 6–12 dental materials, 13 3D printing, 14–16 and other fields 17,18 because of its excellent characteristics, such as environmental protection, high efficiency, energy saving, economy, and enablement. The formulations of UV curable coatings consist of the photoactive resin, reactive diluent, photoinitiator, and other additives 19 .…”

The effect of surface morphology on the peel performance of UV-induced adhesion-reducing adhesives

“…The adhesives of light/heat induced dual curing debonding are generally prepared from various acrylate polymers, reactive diluents, photoinitiators, and heat curing agents [17][18][19]. Zhu et al [20] prepared a polyacrylate pressure-sensitive adhesive by light/heat double curing. The tack force and peel strength of the adhesive decreased with the increase content of the thermal cross-linker KL-1202.…”

Preparation and UV‐curing properties of oxazolidine‐2‐one based acrylates

“…Photo‐curing technology has attracted increasing attention both in academic and in industry 1,2 due to the green technology with “5E” characteristics such as economical, efficient, energy saving, environment friendly and enabling. Currently, the technology is widely used in coatings, 3–7 adhesives, 8 3D printing 9–13 and dental materials, 14 etc. However, in the presence of oxygen, the monomer radical or polymeric radical was trapped by oxygen molecular forming lower active peroxyl radical, resulted in lower polymerization rate.…”