Light‐activated tissue adhesives are limited to low light doses (50 J) and intensities (<1 W cm−2) due to photo‐to‐thermal heat generation. Low intensities have the disadvantage of limited penetration depths with retarded crosslinking kinetics, which impairs carbene‐based crosslinking strategies that compete with nitrogen evolution and gas nucleation. These limitations are circumvented by a trade‐off between high‐intensity activation while reducing the exposure surface area. Continuous or pulsed activation by line scanning the carbene precursor adhesive allows curing a higher surface area/volume ratio while preventing localized heat generation. By optimizing irradiation with a pulsed laser scan, the adhesion strength is improved by 17‐fold over ultraviolet A (UVA) light emitting diodes (LEDs) and is on par with bioadhesive gold standard of topical cyanoacrylates. Overall, this improved method of photo‐activation applies to other industrial and clinical photocuring adhesives where limits on UVA dose constrain exposure intensities.

Poly (vinylidene fluoride) (PVDF) is widely utilized for its unique pyro and piezoelectric properties related to its electro-active β-PVDF. In the past few decades, methods of producing β-PVDF by mechanical stretching of non-polar α-PVDF have been extensively documented. The aim of the present study is to understand the correlation between phase and mechanical behavior of β-PVDF obtained directly from spin-coating, and its stretch-induced transformation from α-PVDF. The effect of thermal annealing and in-plane anisotropy on mechanical properties of spin-coated PVDF freestanding thin films is investigated, under in-situ tensile loading, in conjunction with digital image correlation, to measure the full-field deformation. Stress-strain behavior of spin-coated β-PVDF and α-PVDF are correlated with mechanical stretchinduced phase transformation in α-PVDF. The mechanical strength and failure strain exhibited by spin-coated and annealed α-PVDF

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