Near-infrared / infrared spectroscopic birefringence imaging of polymeric materials

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K21104
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Analytical chemistry; Polymer/Textile materials
• Research Institution: Kyoto University
• Principal Investigator: Hikima Yuta 京都大学, 工学研究科, 助教 (50721362)
• Research Collaborator: MUROGA Shun 京都大学, 大学院 工学研究科 ; MITSUI Ryoki 京都大学, 大学院 工学研究科
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 近赤外分光法 / 赤外分光法 / イメージング / 複屈折 / 球晶

Outline of Final Research Achievements

We developed the evaluation technique of the birefringence, which is a material property of optical anisotropy, from NIR spectrum obtained with linear polarizers. NIR transmission spectra of birefringent materials measured with two polarizers were different from the spectrum measured with the single polarizer. The retardation, which is the product of birefringence and thickness of sample, was calculated by fitting the NIR transmission spectra obtained using two polarizers with a function induced from polarization theory. The reliability of calculated retardation from the polarized NIR spectrum was confirmed by the good linearity between the calculated retardation values of the layered optical films and the number of layers. The proposed method was applied for visualizing a poly (L-lactic acid) banded spherulites. The two-dimensional images of the quantitative birefringence and IR absorption indicated the obvious band-structure and the area where crystalline PLA existed, respectively.

Free Research Field

高分子材料の分析