Pressure-sensitive hotmelt adhesives (HMPSA) are mainly based on synthetic rubbers (styrene-butadiene copolymers or styrene-isoprene copolymers) and they are widely used in the manufacture of items such as tapes, labels, and hygienic and medicals products.
In this work, we present some pressure-sensitive hotmelt adhesives prepared with EVA copolymers as an alternative to the rubber formulations made with styrene-butadiene copolymers (SBS) or styrene-isoprene copolymers (SIS). In general terms, the EVA copolymers show better UV radiation, oxidative and thermal resistance than the rubber copolymers as they do not include double bonds in their structure. We present some HMPSA formulations that include different EVA copolymers, rosin tackifier and different types of plasticisers. EVA copolymers with high comonomer content can improve the tack properties of these formulations due to a reduction of the crystallinity and glass transition temperature. Dynamic rheology analysis has been used to characterise these adhesives.
Co-authors: Susana Caveda Cepas, Carolina Ruiz Orta, Ana Urdiales Sánchez, José Miguel Martín-Martínez, Carmen Sierra Escudero