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Abstract BackgroundPressure-sensitive adhesives (PSAs) are integral to various industrial applications, yet a significant gap remains in accurately assessing their impact properties under dynamic conditions. This limitation hampers the optimization of PSAs for specific uses where impact resistance is critical. ObjectiveThis study aims to develop an experimental method to evaluate the impact properties of PSAs, providing a reliable and reproducible technique to assess their performance. MethodWe designed an experimental setup to simulate real-world impact conditions, incorporating high-speed cameras and an image analysis algorithm to capture the adhesive's behavior under sudden loads. The method's novelty lies in its ability to quantify maximum failure load and adhesion failure mechanisms in the dynamic loading of PSAs. ResultsThe experimental results reveal critical insights into the impact resistance of various PSA formulations, highlighting significant differences in energy dissipation and failure patterns. ConclusionThese findings offer new data not previously available in the literature, enabling a more precise evaluation of PSA performance. The developed method provides a robust framework for assessing the impact properties of PSAs, offering valuable guidance for the design and selection of adhesives in applications requiring enhanced impact resistance. This work bridges the gap between quasi-static testing and realistic dynamic performance, contributing to the advancement of PSA technology.
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Ultra Rate‐Dependent Pressure Sensitive Adhesives Enabled by Soft Elasticity of Liquid Crystal Elastomers
Abstract The fabrication of pressure sensitive adhesives (PSAs) using liquid crystal elastomers (LCEs), which are known for their excellent dissipation properties, is explored in this work. The adhesive properties of the PSAs are evaluated using the 180° peeling test at various conditions. The performance of the LCE adhesives is found to show significant rate and temperature dependence. When the adhesion energy is plotted against the rate, LCE shows an anomalously large power law exponent (n≈ 1.17) compared to existing PSAs (n≈ 0.1–0.6). The unusual rate sensitivity is hypothesized to originate from the synergy of soft elasticity and non‐linear viscoelasticity. The adhesive properties at various rates and temperatures are correlated to the results from dynamic mechanical analysis. Moreover, the large strain stiffening behavior of LCE under uniaxial tension reveals the distinctive advantages offered by LCE as adhesives. Time‐temperature superposition is used to obtain a master curve of adhesion energy that spans rates beyond typical experimental limits. The extreme rate dependence and the large strain stiffening of LCE yield a new category of adhesives that possess special properties, such as reversible adhesion and impact resistance, unlike traditional adhesives.
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- Award ID(s):
- 1752449
- PAR ID:
- 10484872
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 34
- Issue:
- 1
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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