@article{56e0bdbb97ca497f90896f96df400125,
title = "Fabrication and Deformation of Mechanochromic Nanocomposite Elastomers Based on Rubbery and Glassy Block Copolymer-Grafted Silica Nanoparticles",
abstract = "The strength of silica-based mechanochromic nanocomposites was improved by a novel nanocomposite synthesized by grafting poly(butyl acrylate) (PBA)-b-poly(methyl methacrylate) (PMMA) from silica nanoparticles (SiNP). Samples with different PMMA/PBA ratios were prepared to clarify the effect of the rubbery/glassy block copolymer ratios on the mechanical properties of the nanocomposites. The nanocomposites formed a face-centered cubic paracrystal-like structure and exhibited structural color. Time-resolved ultrasmall-angle X-ray scattering was carried out to investigate the structural evolution of the nanocomposites by uniaxial and biaxial mechanical deformation. Changes in color and mechanochromic properties were observed at varying distances between the particles by mechanical deformation. The nanocomposites exhibited elastic and plastic properties and became more rubber-like as the rubbery PBA weight ratio increased. The polymer brush deformed into a prolate spheroid by uniaxial stretching, and the distance between SiNP decreased in the direction perpendicular to elongation, which resulted in the color change by mechanical deformation. Moreover, the distance between SiNP increased isotropically by biaxial stretching. The polymer brush was elongated isotropically toward the in-plane direction and deformed into an oblate spheroid.",
author = "Cheng, {Chao Hung} and Shiori Masuda and Shuhei Nozaki and Chigusa Nagano and Tomoyasu Hirai and Ken Kojio and Atsushi Takahara",
note = "Funding Information: This work was supported by the Impulsing Paradigm Change through Disruptive Technology (ImPACT) Program from the Ministry of Education Culture, Sports, Science and Technology, Japan. We are also grateful for the support from the JST-Mirai Program Grant Number JPMJMI18A2 Japan. Ultrasmall-angle X-ray scattering measurements were done at BL05XU, BL19B2 (Proposal Nos. 2015B1023, 2016A1018, 2016B1034, 2017A1028 2017B1016, 2018A1030, 2018A1036, 2019A1656, and 2019B1730), and BL20XU (Proposal Nos. 2016A1031, 2016B1035, 2017A1029, 2017B1025, 2018A1008 and 2018B1024) in the SPring-8 facility with the approval of the Japan Synchrotron Radiation Research Institute. We gratefully acknowledge Dr. Keiichi Osaka (JASRI), Dr. Taiki Hoshino (RIKEN), Dr. So Fujinami (RIKEN), and Dr. Tomotaka Nakatani (RIKEN) for their assistance on the USAXS measurement. Funding Information: This work was supported by the Impulsing Paradigm Change through Disruptive Technology (ImPACT) Program from the Ministry of Education, Culture, Sports, Science and Technology, Japan. We are also grateful for the support from the JST-Mirai Program Grant Number JPMJMI18A2, Japan. Ultrasmall-angle X-ray scattering measurements were done at BL05XU, BL19B2 (Proposal Nos. 2015B1023, 2016A1018, 2016B1034, 2017A1028, 2017B1016, 2018A1030, 2018A1036, 2019A1656, and 2019B1730), and BL20XU (Proposal Nos. 2016A1031, 2016B1035, 2017A1029, 2017B1025, 2018A1008, and 2018B1024) in the SPring-8 facility with the approval of the Japan Synchrotron Radiation Research Institute. We gratefully acknowledge Dr. Keiichi Osaka (JASRI), Dr. Taiki Hoshino (RIKEN), Dr. So Fujinami (RIKEN), and Dr. Tomotaka Nakatani (RIKEN) for their assistance on the USAXS measurement. Publisher Copyright: Copyright {\textcopyright} 2020 American Chemical Society.",
year = "2020",
month = jun,
day = "9",
doi = "10.1021/acs.macromol.9b02031",
language = "English",
volume = "53",
pages = "4541--4551",
journal = "Macromolecules",
issn = "0024-9297",
publisher = "American Chemical Society",
number = "11",
}