The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 29, 2026
Filed:
Jul. 12, 2021
The Regents of the University of California, Oakland, CA (US);
Qibing Pei, Calabasas, CA (US);
THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, Oakland, CA (US);
Abstract
A solid state thermochromic polymer film comprising two or more separated solid phases with matched refractive indices, wherein the separated solid phases are transparent; and one of the phases undergoes a crystal melting above a threshold temperature resulting in significant reduction of its refractive index. The one of the phases undergoing the crystal melting becomes opaque when its temperature rises above said threshold temperature; and reverts to being transparent when its temperature lowers to an ambient temperature below said threshold temperature. In one example, the new thermochromic phase-changing copolymer with switchable optical transparency is fabricated via copolymerizing hydrophilic poly(hydroxyethyl acrylate) and hydrophobic poly(hexadecyl acrylate-tetradecyl acrylate). The polymer film is transparent due to matched refractive indices of the phase separated domains, but turns opaque when the long alkyl chains undergoes crystalline melting above 28-32° C. The transmittance modulation is autonomous and reversible.