Self-Standing Nanomembranes of Super-Tough Plastics

Abstract

Nanomembranes are effective coating materials for protecting substrates from external stimuli; however, they are generally not self-standing owing to their low mechanical toughness. Selfstanding nanomembranes would be an innovative development in the field of nanotechnology including miniaturized devices. In this study, self-standing nanomembranes were developed by spin-casting supertough polyamides over dimethylformamide solution. The polyamides were synthesized by the polycondensation of two derivatives of 4,4′diamino-α-truxillic acid (4ATA) with slightly bent diphenylcyclobutane in the core. Mechanical evaluation of the 4ATA polyamides having an appropriate composition of aliphatic diacids revealed a high strain-energy density of 231 MJ m −3 at its maximum, which is significantly tougher than spider silk. The nanocoats with a thickness of several hundred nanometers showing interference fringes were able to be peeled off the glass substrate without breaking, owing to its ultrahigh toughness. The selfstanding nanomembrane would be applied to flexible devices in the future. ■ EXPERIMENTAL SECTION4,4′-Diamino-α-truxillic acid dimethyl ester (M1) and 4,4′-diacetamido-α-truxillic acid (M2) were synthesized as previously described

Synthesis of biobased functional materials using photoactive cinnamate derivatives

“…To obtain high-strength biobased polyamides, various aliphatic dicarboxylic acids were copolymerized with biobased polyamides in predetermined proportions, and the changes in their thermal and mechanical properties were systematically evaluated (Fig. 4a) [64]. Consequently, biobased copolyamide showed a slight decrease in heat resistance but significant increases in strength and elongation, with a tensile strength of up to 400 MPa and an elongation at break up to 36% in the fiber state.…”

Preface to the Françoise M. Winnik Special Issue

“…This special issue celebrates her career with contributions from colleagues across the world. The included papers represent many topical areas, including microgels, elastomers, microbubbles, microemulsions, supramolecular assemblies, and thin films, with critical physical properties enabling applications as broad-ranging as carbon capture, medicine, and electronics. − Nonetheless, many of the papers are fundamental in nature, reflecting Professor Winnik’s enduring commitment to and interest in basic colloid and interfacial science.…”