About

Cécile Chazot is an Assistant Professor of Materials Science and Engineering at Northwestern University. Her research is centered on the development of sustainable manufacturing and recycling processes for polymers and composites through the Sustainable Polymer Innovation Laboratory (SPIn lab). Her work focuses on fiber-based materials, biopolymers, large-scale processing, structural colors, and green chemistry, spanning from fundamental understanding of material properties to applications and industrial deployment. Chazot's contributions to the field have been recognized with awards such as the Materials Research Society Arthur Nowick Graduate Student Award and the Materials Research Society Graduate Student Award, Silver, both in Fall 2021.

Research topics

• Materials science
• Nanotechnology
• Optoelectronics
• Composite material
• Biology
• Chemical engineering
• Physics
• Optics

Selected publications

• Photochromic Cholesteric Liquid Crystals via Arylazopyrazole Functionalization of Hydroxypropyl Cellulose

  Advanced Materials · 2026-03-06

  articleOpen accessSenior authorCorresponding

  Photochromic materials are of interest for low-power colorimetric sensors, reusable displays, and dynamic optical components. Incorporating photoswitches into cholesteric liquid crystalline mesophases can enable photo-induced shifts in structural color. While cellulose ethers, such as hydroxypropyl cellulose (HPC), constitute a promising basis for photonic functional materials, due to their abundance, water solubility, and ability to form structurally colored cholesteric liquid crystals, they do not innately respond to incident irradiation. Here, we introduce light-responsiveness into cellulosic chiral nematic mesophases to create a novel photochromic material with precise spatial control over the displayed structural color. For this purpose, we substitute HPC with varying amounts of a highly stable arylazopyrazole (AAP) side chain capable of rapid photoswitching and investigate how AAP influences the reflection wavelength. We observe that even a small AAP degree of substitution can lead to reversible and repeatable photoresponsive structural color under alternating UV and green light irradiation. By changing the number of AAP side groups, we adjust the magnitude of the wavelength shift from 20 to 130 nm, revealing the highly tunable behavior of these materials. Ultimately, the color of these AAP HPC cholesteric mesophases can be spatially patterned within 5 min of light exposure, demonstrating their applicability for dynamic photochromic displays.

  PublisherDOI

• Tailoring Architecture and Properties of Biodegradable Aliphatic-Aromatic Copolyesters via Interfacial Polymerization

  ACS Applied Materials & Interfaces · 2025-11-06 · 1 citations

  articleSenior authorCorresponding

  Aliphatic-aromatic copolyesters (AAPEs) are widely used in biodegradable packaging due to their balance of thermal stability and enzymatic degradability. However, their synthesis is often hindered by time-consuming protocols, prolonged reactions, and reliance on expensive metal catalysts. Herein, we introduce stirred interfacial polymerization as a rapid, open-air method to synthesize poly(p-phenylene adipate-co-terephthalate) (PPAT) with tunable aliphaticity. We compare the use of chloroform, a conventional organic solvent for interfacial polymerization, with ethyl acetate, a more environmentally friendly alternative. Regardless of the solvent used, we achieved reaction yields that matched or exceeded those of traditional step-growth synthesis methods. Increasing the concentration of phase transfer catalyst enhances the incorporation of the aliphatic monomer, promoting a shift from a random to a more block-like copolymer structure. PPAT powder can be readily heat-pressed into semicrystalline films with degradation onset temperatures between 263 and 310 °C and tailored elastic moduli and hardness values. Furthermore, increased aliphaticity significantly improved enzymatic degradation by PETase, with films containing ∼60% of poly(p-phenylene adipate) units showing over 50% mass loss within 400 h. This work outlines an efficient synthetic pathway for producing enzymatically degradable AAPEs with tailored backbone structures, crystallinity, and thermomechanical properties.

  PublisherDOI

• Structure and Sulfur: Tuning the Viscoelastic and Surface Properties of Natural Keratin Fibers

  Zenodo (CERN European Organization for Nuclear Research) · 2025-07-28

  datasetOpen accessSenior author

  This dataset contains the experimental data presented in the article "Structure and Sulfur: Tuning the Viscoelastic and Surface Properties of Natural Keratin Fibers" published in ACS Materials Au, 2025. DOI: https://doi.org/10.1021/acsmaterialsau.5c00130.

  PublisherDOI

• Structure and Sulfur: Tuning the Viscoelastic and Surface Properties of Natural Keratin Fibers

  ACS Materials Au · 2025-10-30 · 1 citations

  articleOpen accessSenior authorCorresponding

  Natural keratin fibers, such as wool, possess a complex hierarchical structure that governs their mechanical properties and surface energy. However, the extent to which these characteristics are influenced by combined contributions of structural variations (e.g., fiber diameter, intermediate filament (IF) packing) and chemical composition (e.g., disulfide bond density) remains poorly understood. In this study, we investigate wool fibers from five sheep breeds (Merino, Polwarth, Cheviot, Eider, and Devon) to elucidate how these factors influence viscoelasticity and surface interactions. Using a multimodal approach integrating interfacial and bulk characterization methods, including inverse gas chromatography (IGC), atomic force microscopy-infrared spectroscopy (AFM-IR), X-ray photoelectron spectroscopy (XPS), uniaxial tensile testing, and synchrotron small-angle X-ray scattering (SAXS), we show that the nanometer-thick 18-methyleicosanoic acid (18-MEA) layer is consistently present across all wool types and plays a key role in governing hydrophobicity and surface heterogeneity. A controlled isothermal treatment at 200 °C, designed to cleave disulfide bonds, results in a nearly 40% reduction in specific surface area across all fiber types, accompanied by a significant decrease in tensile strength and 80% reduction in elongation at break for Merino and Devon wool, but limited influence on the mechanical properties of Eider fibers. Furthermore, rate-dependent tensile testing within the elastic regime reveals distinct viscoelastic responses among the fiber types, suggesting that the sulfur-rich protein matrix surrounding IFs and its structure contribute actively to stress partitioning. Altogether, when combined with conclusions from SAXS measurements of IF spacing, our work offers compelling insights into the role of the keratin-associated protein (KAP) matrix in shaping wool fiber mechanics. Differences in mechanical behavior among wool types, despite similar IF spacing or sulfur content, highlight the importance of matrix composition and cross-linking density, suggesting that the molecular architecture of the KAP network may be a dominant factor in determining fiber performance.

  PublisherDOI

• The Hierarchical Structure of Sheep Wool and Its Impact on Physical Properties

  Advanced Functional Materials · 2025-08-13 · 5 citations

  articleOpen accessSenior authorCorresponding

  Abstract Sheep wool, the most abundant and versatile natural α‐keratinous fiber, showcases extraordinary genetic diversity due to the myriad breeds cultivated over centuries worldwide. This diversity presents a unique opportunity to explore a broad range of morphologies and textile‐relevant properties, such as mechanical strength and hydrophilicity, positioning wool as an exceptional model system for α‐keratinous fibers and materials. Despite the maturity of the science surrounding hair and wool, fundamental understanding of the structure‐property relationships across organizational levels, from chemical structure to nanoscale self‐assembly and microstructural topography, remains elusive. In this study, a comprehensive characterization of wool fibers from multiple breeds is conducted to investigate the connections between morphological structures at different length scales and their textile‐relevant mechanical and interfacial properties. Employing imaging and spectroscopy methods, the fibers' microstructure, protein conformation, and chemical composition are quantified. This thorough analysis reveals correlations between protein secondary structure, polymer crystallinity, and microstructure, bridging multiple ordering length scales. Additionally, the interfacial and mechanical properties of the wool fibers are assessed through tensiometry and uniaxial tensile testing, correlating elastic properties and surface energy with hierarchical ordering. This work provides the most detailed exploration of sheep wool's structure and properties to date, offering valuable design rules for α‐keratinous materials.

  PublisherOA PDFDOI

• Structure and Sulfur: Tuning the Viscoelastic and Surface Properties of Natural Keratin Fibers

  Zenodo (CERN European Organization for Nuclear Research) · 2025-07-28

  datasetOpen accessSenior author

  This dataset contains the experimental data presented in the article "Structure and Sulfur: Tuning the Viscoelastic and Surface Properties of Natural Keratin Fibers" published in ACS Materials Au, 2025. DOI: https://doi.org/10.1021/acsmaterialsau.5c00130.

  PublisherDOI

• 3D Printing of Poly(methyl methacrylate) by Interfacial Photopolymerization

  ACS Applied Materials & Interfaces · 2025-09-16 · 2 citations

  article

  Established light-based additive manufacturing (AM) processes, such as vat polymerization, utilize nonrecyclable thermoset polymers, posing sustainability concerns. This work presents a method for circular photopolymerization three-dimensional (3D) printing of thermoplastic parts, addressing the demand for low-waste production of complex, high-resolution polymer parts. This is achieved through interfacial photopolymerization (IPP), where linear polymer chains form layerwise into entangled networks at the interface between the immiscible organic and aqueous phases. IPP has previously been demonstrated, but with limited chemistries and without 3D structural control. We demonstrate herein a chemistry to form poly(methyl methacrylate) (PMMA) by IPP and a process for multilayer fabrication in a modified commercial projector-based 3D printer. Layer resolution and stability are enhanced using light-absorbing dye and a water-soluble polyethylene glycol (PEG) binder. Postprocessing with controlled air drying and thermal treatment with PEG infiltration preserves geometry and reduces cracking. The resulting composite comprises 75% PEG and 25% PMMA with mechanical properties akin to those of polymer foams. Circularity of the IPP-PMMA process is demonstrated by recycling and reincorporating printed objects across several cycles without significant degradation of properties. Although enhancements in geometric fidelity and mechanical properties are necessary, IPP 3D printing enables, for the first time, digital light processing of recyclable thermoplastic PMMA and PEG-based parts.

  PublisherDOI

• A roll-to-roll chitosan finishing strategy for elastane recovery

  RSC Applied Polymers · 2025-01-01

  articleOpen accessSenior author

  Roll-to-roll dip-coating of elastane with a dissolvable chitosan layer is introduced to enable recovery from fiber blends. This approach targets key recycling barriers, preserves elastane integrity, and may aid separation from mixed textile waste.

  PublisherOA PDFDOI

• Dynamic Structural Colors in Cholesteric Cellulose Composites: Achieving Spatial and Temporal Control

  Advanced Optical Materials · 2025-06-14

  articleOpen accessSenior authorCorresponding

  Abstract Structurally‐colored cholesteric cellulose ether materials offer a sustainable alternative to traditionally‐dyed plastics. These materials are produced by dissolving high concentrations of cellulosic polymers in a monomeric solvent, forming a liquid crystalline mesophase, and polymerizing to kinetically trap the ordered arrangement in a composite. Despite significant advancements in fabricating colorimetric films and devices using this method, the lack of critical design rules for predicting color evolution upon polymerization hinders large‐scale deployment and rational design. In this work, ethyl cellulose‐poly(acrylic acid) films are used as a model system to explore how the balance between polymer chain mobility and solvent photopolymerization kinetics affect the preservation of cholesteric texture and optical properties. These findings reveal that the observed blue‐shift in reflectivity is linked to the realignment or disruption of chiral nematic order during poly(acrylic acid) chain growth. Time‐resolved studies during UV curing, including in situ reflection spectroscopy and rheometry, demonstrate that rapid polymerization and reduced polysaccharide mobility are key to maintaining the color and angle‐dependent optical appearance in the final films. Applying these fundamental design principles, we create composites with spatially‐controlled photopatterned colors, tailored angle‐resolved reflectivity that resists photobleaching, and reversible colorimetric functions that are unattainable with pigmented plastics.

  PublisherOA PDFDOI

• SPHERES: A MATLAB Tool for Teaching Solubility Parameter Calculations in Polymer Processing and Recycling

  Journal of Chemical Education · 2025-10-14

  articleSenior authorCorresponding

  Solubility parameters are a fundamental tool in chemistry and chemical engineering for predicting and comparing the solubility of organic molecules and polymers. Group contribution (GC) theory simplifies these predictions by summing the cohesive energy contributions of functional groups within a molecule. However, as molecular complexity increases, manual calculations become cumbersome and error prone. To address this challenge, we developed Stefanis–Panayiotou and Hansen Evaluation and Reference Engine for Solubility (SPHERES), a user-friendly MATLAB application that calculates Hansen Solubility Parameters (HSPs) using both Hansen and Stefanis–Panayiotou GC frameworks. This program streamlines the calculations, enabling rapid and accurate HSP predictions for a wide range of molecular structures. We validated SPHERES against published data for common solvents and polymers. Its novel grouping feature allows users to combine moieties in custom subgroups for facile calculation of complex macromolecules, demonstrated with elastane, a copolymer widely used in textiles. While elastane’s complex molecular structure hinders recycling by traditional methods, SPHERES highlights potential selective dissolution pathways via efficient solvent selection. SPHERES was implemented in a graduate-level polymers course where students used it to understand the advantages of each GC framework, investigate polymer–solvent interactions, and apply solubility theory in practical scenarios. Students reported that SPHERES significantly reduced calculation time and minimized errors, enhancing both learning and problem-solving efficiency. SPHERES serves as a valuable resource for students, educators, and researchers, offering a practical, flexible approach to solubility parameter prediction.

  PublisherDOI

Frequent coauthors

• A. John Hart

  10 shared

• Adri C. T. van Duin

  Pennsylvania State University

  5 shared

• Behzad Damirchi

  Theravance Biopharma (United States)

  5 shared

• Jeffrey L. Gair

  4 shared

• Driffa Guerfa

  4 shared

• Matthieu Lancry

  Université Paris-Saclay

  4 shared

• John Hart

  Massachusetts Institute of Technology

  4 shared

• Pierre C. Dromel

  4 shared

Awards & honors

• Materials Research Society Arthur Nowick Graduate Student Aw…
• Materials Research Society Graduate Student Award, Silver (F…