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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.

The use of conductive self‐healing hydrogels in electronic devices not only reduces replacement and maintenance costs but also prolongs their lifetime. Therefore, developing hydrogels with autonomous self‐healing properties and electronic conductivity is vital for the advancement of emerging fields, such as conductors, semiconductors, sensors, artificial skin, and electrodes and solar cells. However, it remains a challenge to fabricate a hydrogel with high conductivity that can be healed quickly at room temperature without any external stimulus. In this work, we report an effective and simple free radical polymerization approach to synthesizing a hydrogel using modified rGO and acrylate monomers containing abundant ion groups. The hydrogel exhibits excellent electronic conductivity, extremely fast electronic self‐healing ability, and excellent repeatable restoration performance at 25 °C. The conductivity of the hydrogel reaches 27.2 S/m, the hydrogel recovers its original shape, and scoring scratched on the surface totally disappears after holding at 25 °C for 40 s. This conductive, room‐temperature self‐healing hydrogel takes unique advantage of supramolecular chemistry and polymer nanoscience and has potential applications in various fields such as self‐healing electronics, artificial skin, soft robotics, biomimetic prostheses, and energy storage. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47379.

A series of aromatic hyperbranched polyesters (HBPEs) were synthesised through one-pot reaction of benzene-1,2,4tricarboxylic anhydride, diethylene glycol, and methanol. The molecular structure of HBPEs was characterised by 1 H-NMR, Fourier transform infrared spectroscopy, gel permeation chromatography, differential scanning calorimetry (DSC), and thermogravimetric analysis. HBPE was used as plasticiser for poly(vinyl chloride) (PVC), and compared with traditional plasticiser bis(2-ethylhexyl) phthalate (DOP). When the plasticiser concentration in PVC was below 40 wt-%, HBPE showed better plasticisation efficiency than DOP, with enhanced impact strength and ultimate elongation. Volatility and extractability tests for PVC films indicated that there was no migration if HBPE was used as plasticiser, even under very harsh conditions, while the migration in PVC films plasticised by DOP was much greater, indicating that HBPE could be used as a substitution for DOP to lower the potential health risk from migrating phthalates during the use of PVC products.

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