Heat resistance of acrylic pressure‐sensitive adhesives based on commercial curing agents and UV/heat curing systems

ABSTRACT The development of adhesive tapes that can be applied at high temperature is a major challenge for pressure‐sensitive adhesives (PSAs). To date, the heat resistance of PSAs has not been investigated in sufficient details. In this study, based on the relationship between curing structures and properties, a series of acrylic PSAs with excellent heat resistance were prepared. Commercial zirconium acetylacetonate (ZrACA), desmodur L75 (L75), and N , N , N ′, N ′‐tetrakis(2,3‐epoxypropyl)‐ m ‐xylene‐α,α′‐diamine (GA240) were employed as heat‐curing agents. Trimethylolpropane triacrylate (TMPTA) was used as ultraviolet (UV)‐curing agent to form semi‐interpenetration polymer network structures after UV exposure. The influences of different curing agents on the thermal stability, adhesion performance, gel fraction, and viscoelastic of PSAs were explored. The results showed that the PSAs cured by L75, GA240, and TMPTA exhibited excellent heat resistance. Especially, when the content of L75 was 1.0 wt %, the PSAs could be peeled off substrate without residues on substrate surface after treatment at 170 °C for 4 h, while the nonmodified acrylic PSAs possessed residues after treatment from 110 °C. The cured PSAs adhesive performance was evaluated showing maximum 180° peel strength of 16.7 N/25 mm comparable to current PSAs. These resulting PSAs showed high heat resistance and they are suitable for a broad range of special fields. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 47310.