A Self‐Healing Nanofiber‐Based Self‐Responsive Time‐Temperature Indicator for Securing a Cold‐Supply Chain. Issue 11 (5th February 2020)

• Record Type: Journal Article
• Authors: Choi, Sejin; Eom, Youngho; Kim, Seon‐Mi; Jeong, Da‐Woon; Han, Jongmin; Koo, Jun Mo; Hwang, Sung Yeon; Park, Jeyoung; Oh, Dongyeop X.
• Is Part Of: Advanced materials. Volume 32:Issue 11(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-02-05
• Subjects: foodborne illness -- self‐healing nanofibers -- thermodynamic energy -- time‐temperature indicators -- transparency; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201907064
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Perishable foods at undesired temperatures can generate foodborne illnesses that present significant societal costs. To certify refrigeration succession in a food‐supply chain, a flexible, easy‐to‐interpret, damage‐tolerant, and sensitive time‐temperature indicator (TTI) that uses a self‐healing nanofiber mat is devised. This mat is opaque when refrigerated due to nanofiber‐induced light scattering, but becomes irreversibly transparent at room temperature through self‐healing‐induced interfibrillar fusion leading to the appearance of a warning sign. The mat monitors both freezer (−20 °C) and chiller (2 °C) successions and its timer is tunable over the 0.5–22.5 h range through control of the polymer composition and film thickness. The thin mat itself serves as both a temperature sensor and display; it does not require modularization, accurately measures localized or gradient heat, and functions even after crushing, cutting, and when weight‐loaded in a manner that existing TTIs cannot. It also contains no drainable chemicals and is attachable to various shapes because it operates through an intrinsic physical response. Abstract : Innovative time–temperature indicators with superior performance and extreme stability are engineered using self‐healing nanofibers. Owing to the intrinsic response of the self‐healable elastomer, highly sensitive, reliable, and tunable operation is enabled through morphological conversion. The self‐responsive working principle is driven by thermodynamic stability and liberates these indicators from the physical limitations and chemical hazards of existing devices.