Abrasion tolerant, non-stretchable and super-water-repellent conductive & ultrasensitive pattern for identifying slow, fast, weak and strong human motions under diverse conditions

Abstract

The conversion of mechanical deformation into electrical signals is a widely used principle for various relevant applications. Facile & scalable fabrication, ultrahigh-sensitivity, low-response time and uninterrupted performance at severe conditions...

Michael Addition Reaction Assisted Derivation of Functional and Durable Superhydrophobic Interfaces

“…93 In this context, Das et al exploited the facile and catalyst-free Michael addition reaction to fabricate a metal-free, low-strain assisted, ultrasensitive, durable, superhydrophobic strain sensor. 83 A chemically "reactive" conductive ink was prepared by mixing 3aminopropyltrimethoxysilane and amino-graphene oxide. The "amine" loaded conductive ink was strategically and spatially selectively deposited on a chemically "reactive" porous paper substrate following the 1,4-conjugate addition reaction as shown in Figure 11M.…”

“…Such characteristics are of utmost importance for realistic and diverse applications of the bioinspired coating. In this regard, the environment-friendly Michael addition reaction between amine and acrylate requiring mild operational conditions would provide a prospective platform to tailor the bioinspired water wettability and other relevant physical properties (Figure )including transparency, mechanical property, porosity, etc.following simple and scalable fabrication processes. − In the past, the catalyst-free Michael addition reaction was successfully extended to produce amplified “reactive” surfaces. , Ford et al studied the ability of growing different nanostructures on selected substrates following the catalyst-free aza-Michael addition reaction between branched polyethylenimine (BPEI) and dipentaerythritol penta-acrylate (5-Acl) that resulted in hyperbranched poly­(ester amines) cross-linked thin films with surface amplified functional groups . In 2012, Bechler et al capitalized on this concept of a nanostructured, “reactive” polymeric film of BPEI/5Acl to construct a relatively thick (∼750 nm) multilayer coating following the layer-by-layer deposition approach .…”

“…To overcome this challenge, the Michael addition reaction between BPEI and 5Acl was employed strategically to achieve rapid and controlled growth of chemically “reactive” nanocomplexes (CRPNCs) in solution phase, instead of on a solid surface. The research group of Manna et al introduced and extended these solution phase CRPNCs for developing porous, three-dimensional superhydrophobic monoliths and flexible polymeric superhydrophobic coatings for applications in oil/water separation, ,,− ,,− ,, drug delivery, ,, patterned interfaces, ,,, etc. The controlled growth of CRPNCs through Michael addition reaction and its strategic postcovalent modifications allowed different durable bioinspired wettabilities to be adoptedincluding controllable adhesive/nonadhesive superhydrophobicity, hydrophilic/superhydrophobic patterns, chemically “reactive” superhydrophobicity, and stimuli-responsive superhydrophobicityfollowing simple and scalable fabrications processes. − The as fabricated chemically “reactive” interfaces with tailorable water wettability exhibited impeccable durability and performance at even chemically harsh and challenging settings.…”

“…The research group of Manna et al introduced and extended these solution phase CRPNCs for developing porous, three-dimensional superhydrophobic monoliths and flexible polymeric superhydrophobic coatings for applications in oil/water separation, ,,− ,,− ,, drug delivery, ,, patterned interfaces, ,,, etc. The controlled growth of CRPNCs through Michael addition reaction and its strategic postcovalent modifications allowed different durable bioinspired wettabilities to be adoptedincluding controllable adhesive/nonadhesive superhydrophobicity, hydrophilic/superhydrophobic patterns, chemically “reactive” superhydrophobicity, and stimuli-responsive superhydrophobicityfollowing simple and scalable fabrications processes. − The as fabricated chemically “reactive” interfaces with tailorable water wettability exhibited impeccable durability and performance at even chemically harsh and challenging settings. The strategic use of the catalyst-free Michael addition reaction allowed the successful modulation of mechanical property, porosity, shrinkage, optical transparency, etc.…”

“…(O–Q) Depicting the superhydrophobic sensor, Bluetooth module, and smart phone as a data output device for wireless monitoring of different human expressions (P) and motions (Q). Reproduced with permission from ref . Copyright 2021 The Royal Society of Chemistry.…”