TY - JOUR

T1 - Optical Reflectance of Composites with Aligned Engineered Microplatelets

AU - Poloni, Erik

AU - Galinski, Henning

AU - Bouville, Florian

AU - Wilts, Bodo

AU - Braginsky, Leonid

AU - Bless, David

AU - Shklover, Valery

AU - Sicher, Alba

AU - Studart, André R.

N1 - The authors thank the Swiss National Science Foundation for the financial support through project number 200021_160184 and through the National Center of Competence in Research (NCCR) Bio‐Inspired Materials (Grant No. 51NF40‐182881). Prof. Dr. Eric Dufresne and Dr. Robert Style (ETH Zürich) were greatly acknowledged for their fruitful discussions. Публикация для корректировки.

PY - 2023/4/4

Y1 - 2023/4/4

N2 - The reflection of light from distributed microplatelets is an effective approach to creating color and controlling the optical properties in paints, security features, and optical filters. However, predictive tools for the design and manufacturing of such composite materials are limited due to the complex light–matter interactions that determine their optical response. Here, the optical reflectance of individual reflective microplatelets and of polymer-based composites containing these engineered platelets as an aligned, dispersed phase are experimentally studied and analytically calculated. Transfer-matrix calculations are used to interpret the effect of the platelet architecture, the number of platelets, and their size distribution on the experimentally measured reflectance of composites prepared using a previously established magnetic alignment technique. It is demonstrated that the reflectance of the composites can be understood as the averaged response of an array of Fabry–Pérot resonators, in which the microplatelets act as semi-transparent flat reflectors and the polymer as cavity medium. By using an analytical model and computer simulations to describe the interaction of light with platelets embedded in a polymer matrix, this work provides useful tools for the design and fabrication of composites with tailored optical reflectance.

AB - The reflection of light from distributed microplatelets is an effective approach to creating color and controlling the optical properties in paints, security features, and optical filters. However, predictive tools for the design and manufacturing of such composite materials are limited due to the complex light–matter interactions that determine their optical response. Here, the optical reflectance of individual reflective microplatelets and of polymer-based composites containing these engineered platelets as an aligned, dispersed phase are experimentally studied and analytically calculated. Transfer-matrix calculations are used to interpret the effect of the platelet architecture, the number of platelets, and their size distribution on the experimentally measured reflectance of composites prepared using a previously established magnetic alignment technique. It is demonstrated that the reflectance of the composites can be understood as the averaged response of an array of Fabry–Pérot resonators, in which the microplatelets act as semi-transparent flat reflectors and the polymer as cavity medium. By using an analytical model and computer simulations to describe the interaction of light with platelets embedded in a polymer matrix, this work provides useful tools for the design and fabrication of composites with tailored optical reflectance.

KW - alumina

KW - epoxy

KW - manufacturing

KW - reflective materials

KW - titania

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85146652898&origin=inward&txGid=27da624abeaa3dde4e355f7dbbbda866

UR - https://www.mendeley.com/catalogue/885e1d64-5256-372b-9694-f94f6157b279/

U2 - 10.1002/adom.202201989

DO - 10.1002/adom.202201989

M3 - Article

VL - 11

JO - Advanced Optical Materials

JF - Advanced Optical Materials

SN - 2195-1071

IS - 7

M1 - 2201989

ER -