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ABSTRACT Polydopamine (PDA) is a biopolymer, which can form uniform thin films on almost all solid substrates as well as at the liquid/air interface. Carbonized polydopamine possesses graphite-like structure and exhibits high electrical conductivity, which makes it a potential carbon-based thin film conductor. However, studies on mechanical behavior of PDA and its derived materials are very limited. In this study, PDA samples were synthesized through self-assembly of dopamine in aqueous solution. Elastic modulus of thin films was measured using the nanoindentation technique. It is shown that the Young’s modulus of PDA thin film increased with increasing heat treatment temperature (up to 600°C). Doping with Cu ions also increased the Young’s modulus of PDA. Furthermore, all PDA thin films, with and without Cu, exhibited creep behavior.
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This content will become publicly available on June 22, 2026
ThermAssist: Augmenting Heat Perception in Plastic Thermoforming Using Colorimetric Spray-on Diacetylene Polymer Sensors
The practice of thermoforming plastics relies on understanding the effects of temperature. Although simulations can predict these effects with precise material and equipment parameters, they often fail to communicate experiential knowledge of how different materials and processes interact. Tactile feedback and visual cues are central to determining whether a material is malleable, a skill that simulations cannot replicate. Our work explores the use of a heat-sensitive spray-on smart material made from polydiacetylene (PDA) to improve heat perception. This sensor exhibits reversible colorimetric changes in response to temperature variations from 100ºC to 200ºC, acting as a visual cue perceivable by humans. This study evaluates the sensitivity, accuracy, and practicality of PDAs in real-time temperature monitoring during vacuum forming and acrylic bending. Our findings demonstrate that PDA based sensors enhance visibility of material dispersion, provide safeguards to critical temperatures, and illustrate heat flow and conductivity, thereby improving accessibility, literacy, and relationships with materials in thermoforming practices.
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- Award ID(s):
- 2150321
- PAR ID:
- 10624059
- Publisher / Repository:
- ACM
- Date Published:
- ISBN:
- 9798400712890
- Page Range / eLocation ID:
- 517 to 526
- Format(s):
- Medium: X
- Location:
- Virtual United Kingdom
- Sponsoring Org:
- National Science Foundation
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