Butyl acrylate/4-acryloyloxy benzophenone copolymers as photoreactive UV-crosslinkable pressure-sensitive adhesives
It has previously been shown that copolymers of butyl acrylate with 4-acryloyloxy benzophenone can be used as pressure-sensitive adhesives (PSAs). This paper presents the synthesis and application of a solvent-borne polymer system for the preparation of photoreactive UV-crosslinkable acrylic pressure-sensitive adhesives. Butyl acrylate/benzophenone copolymers with molecular mass in the range 180 000 to 480 000 Dalton were prepared by carrying out free-radical solution polymerization. These copolymers were found to be tacky but in some cases to possess insufficient cohesive strength after UV-crosslinking to be useful as PSAs. The other copolymers resulted in materials with the balance of cohesive and adhesive characteristics required of good PSAs. Some of the parameters affecting the pressure-sensitive adhesive properties of the copolymers are the concentration of 4-acryloyloxy benzophenone, the molecular mass of the polymeric components, the UV-reactivity, and properties such as tack, peel adhesion, and cohesion.
UV-crosslinkable warm-melt pressure-sensitive adhesives based on acrylics
The target of this article is to show the preparation of new generation of UV-crosslinkable warm-melt acrylic pressure-sensitive adhesives (PSAs) and the experimental test of their adhesive properties in comparison with typical conventional hot-melts adhesives. New generation of UV-crosslinkable acrylic warm-melts PSAs containing unsaturated photoinitiator, incorporated during polymerization process into polymer chain, and photoreactive diluents added to PSA systems after polymerization allows producing of wide range of self-adhesive materials, such as labels, mounting tapes, masking and splicing tapes, and sign and marking films.
Development of photoreactive UV-crosslinkable solvent-free acrylic pressure-sensitive adhesives coated at room temperature and used for removable and repositionable self-adhesive materials
The goal of this article is to review the development of photoreactive UV-crosslinkable acrylic pressure-sensitive adhesives (PSAs) characterized by low viscosity, which can be coated at room temperature in the form of adhesive layers and are characterized by removable properties after UV-crosslinking. Surfactants and stearic acid have been used to improve the performance of the acrylic PSA, too. They are used for the manufacturing of removable and repositionable self-adhesive products, such as easy peel-able decorative films and wide range version of post-it articles.
Zbigniew Czech, Roland Milker, Agnieszka Butwin and Ewa Herko
Removal of organic solvents for the purpose of manufacturing of solvent-free pressure-sensitive adhesives
The present report reports on the process of the removal of organic solvents in the polymerisation reactor, thin-layer evaporator, and twin-screw extruder for the production of the solvent-free acrylic pressure-sensitive adhesives (PSA). New applications and technical specifications stimulate the continuous development of new methods of manufacturing of non-solvent self-adhesives. The new synthesis of 100% acrylic systems includes solvent polymerisation and finally a removal of volatile organic compounds in a special extruder, polymerisation vessel or an industrial evaporator. The removal process requires controlling such relevant parameters as temperature, pressure and volatile organic compounds concentration.