Removable Pressure-Sensitive Adhesives Based on Acrylic Telomer Syrups

Removable pressure-sensitive adhesives (PSAs) are used in the production of self-adhesive materials such as protective films, masking tapes or biomedical electrodes. This work presents a new and environmentally friendly method obtaining this type adhesive materials, i.e., photochemically induced free radical telomerization. Adhesive binders to removable PSAs, photoreactive acrylic telomer syrups (ATS) were prepared from n-butyl acrylate, acid, 4-acrylooxybenzophenone. Tetrabromomethane (CBr4) bromotrichloromethane (CBrCl3) telogens. ATS was modified with unsaturated polybutadiene resin photoinitiator. compositions coated onto carrier UV cross-linked. The effects chemical nature telomers (i.e., terminal Br Cl atoms) their molecular weight (K-value), well cross-linking degree on properties studied. It found that increase telogen content system, dynamic viscosity K-value decrease, conversion monomers increases. CBr4 turned out be more effective chain transfer agent than CBrCl3. Moreover, Br-atoms (7.5 mmol CBr4), due slightly lower weights viscosity, showed higher photocrosslinking ability (which confirmed by high cohesion results at 20 70 °C, >72 h). Generally, values temperature which failure occurred noted for PSAs based mmol), both excellent result PSA obtained case syrup Br-7.5 crosslinked 5 J/cm2 dose UV-radiation (adhesion ca.1.3 N/25 mm, > 72