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[Display omitted] • Pressure-sensitive adhesive (PSA) exhibiting robust underwater adhesion was developed through the synergistic integration of gallol-functionalization and microscale surface patterning. • Gallol group introduction in a smaller proportion (3.3 mol%) demonstrated more than double the underwater adhesion strength compared to the benzyl (4.3 mol%) or phenol (3.6 mol%) groups. • Surface patterning reduced adhesion loss in water from 62% to 11%. • The pattern on the PSA surface generated drainage channels, effectively reducing defect size and ensuring a uniform distribution of adhesion defects. In this study, we synthesized a gallol-functionalized PSA and generated micropatterns on its surface to improve its underwater adhesion. Compared to the adhesive-substrate interactions of benzyl and phenol-functionalized PSAs in water, Gallol PSA exhibited greater interactions with the substrate. Furthermore, the micropattern on the PSA surface provided a drainage channel for water during the bonding process so that water is not trapped at the substrate-adhesive interface. Moreover, the drainage channel allows the formation of small and uniform adhesion defects, which minimize the deterioration in adhesion caused by water. And the adhesive manufacturing process is also simple, without any gallol protection and deprotection steps, and can be achieved using the current adhesive industry infrastructure. This facile fabrication strategy and its adhesive properties could promote the commercialization of gallol-functionalized PSAs with underwater adhesion. [ABSTRACT FROM AUTHOR]

Abstract: Continuous cooling transformation (CCT) characteristics of microalloyed steels with different tungsten (W) contents (0, 0.1 and 1wt.%) were investigated to obtain the necessary information for heat treatment of these steels. The effects of W addition on the sizes of prior austenite grains and precipitates were analysed. CCT diagrams were obtained by varying the cooling rates from 0.1 to 120°C/s. Transformation characteristics were determined by using dilatometer test, microscopic observation and hardness measurement. The results showed that W had a positive effect on the refinement of prior austenite grains and precipitates. The CCT diagrams exhibited that the ranges of transformation products were shifted to the right side of the diagram when the W content increased. CCT diagram for steel with 0.1% W was similar in shape to that without W. The addition of 1% W induced two separated transformation ranges in the cooling rate range of 0.1 to 1°C/s in the diagram. Both the austenitisation starting and finishing temperatures were raised as W was added. W addition induced decreased critical cooling rates for phase transformations and obtaining complete ferrite+pearlite microstructures. The martensite transformation temperature was decreased after W addition. The addition of W caused increased hardness, and the hardness obeyed an exponential type relationship with cooling rate. [Copyright &y& Elsevier]