Pressure-sensitive adhesives from polyester pentablock copolymers

Abstract

Pressure sensitive adhesives (PSAs) are widely used materials in a number of applications, such as sticky notes and tapes, but for most commercial products they are derived from petrochemicals. Here, a series of pentablock polymers, with an ABABA structure featuring poly(cyclohexene oxide-alt-phthalic anhydride) ‘A’ blocks and poly(ε-decalactone) (PDL) ‘B’ blocks, are prepared as pressure-sensitive adhesives from bio-sourced monomers. The pentablock polymers are prepared by controlled polymerisation techniques, using a single catalyst, in a one-pot process. Polymer properties are tuned through varying the hard block (A) content between 16–39 wt%. Below 25 wt% hard block, the pentablock polymers show low-tack adhesive performance (0.2–0.6 N cm⁻¹) and are removed by adhesive failure. Their adhesive performance compares favourably to low-tack commercial adhesives.