Effect of substrate and tackifier on peel strength of SIS (styrene-isoprene-styrene)-based HMPSAs

SIS (styrene-isoprene-styrene)-based hot-melt pressure-sensitive adhesives (HMPSAs) have high tack, high cohesion (at ambient temperature), and good adhesion to various substrates. In this study, we investigated the effects of the properties of the substrates and tackifier on the characteristics of the SIS-based HMPSAs. SUS (stainless steel), PE, PP, PVC, Bakelite, Teflon, and glass were used as the substrates. The substrates used in this study were classified into three groups (high, medium, and low peel). A similar classification was obtained using surface tension as the distinguishing factor. The maximum peel strength of the HMPSAs made with high softening point (SP) tackifier shifts to lower tackifier content than those made with low SP tackifier. This may be due to blends made with high SP tackifiers that have higher G′ at use temperature than those made with high SP tackifiers.