Design and synthesis of a zero-photoelastic birefringence polymer with a high glass-transition temperature by a random copolymerization method

Abstract

We designed and synthesized a zero-photoelastic birefringence polymer that had a high glass-transition temperature (T g ) by introducing trans-stilbene units into the side chains of the copolymer by a random copolymerization method. The concentration of the trans-stilbene units required to compensate for photoelastic birefringence in the random copolymer was lower than that required in a polymer prepared by an anisotropic molecule dopant method, because the presence of an anisotropic moiety in the side chain of the polymer has a greater effect than an anisotropic molecule doped in the polymer. Furthermore, the polymer with trans-stilbene units in side chains showed a higher T g than the polymer containing an anisotropic dopant. We conclude that the introduction of an anisotropic molecule of a similar or larger size to trans-stilbene into the side chain gives a polymer with a high T g .

Photoreversible Birefringence Change of Diarylethene Single Crystals as Revealed by Change in Molecular Polarizability Anisotropy

“…Moreover, molecules are regularly aligned in crystal, and the refractive index is expressed as the sum of the polarizability . Accordingly, the molecular polarizability anisotropy (α 1 and α 2 ) can be estimated by depicting the polarizability ellipsoid similar to the refractive index ellipsoid . To depict the polarizability ellipsoid, diagonalization of the polarizability tensors as shown in eq is required.…”

“…43 Accordingly, the molecular polarizability anisotropy (α 1 and α 2 ) can be estimated by depicting the polarizability ellipsoid similar to the refractive index ellipsoid. 44 To depict the polarizability ellipsoid, diagonalization of the polarizability tensors as shown in eq 6 is required. The eigenvectors (s, k, and t) and the eigenvalues (α s , α k , and α t ) indicate the ellipsoid axes (the principal axes) and the lengths of the semi-axes of the ellipsoid (principal values), respectively.…”

Stacked polymer waveguide type fan‐in/fan‐out device for dense multi‐core fibre

“…It is speculated that the index contrasts in the y-direction were larger than those in the x-direction because the refractive index of the cladding polymer just upper and under the core was reduced because of the stress-induced photo-elastic effect which was induced during the fabrication process. It is speculated that the birefringence induced by photo-elastic effect can be improved by adopting zero-photo-elastic polymers [22]. Fig.…”

Birefringence- and Optical Distortion-Free Isotropic Polymer Lens Assisted by Photonic Microspheres

“…Polymer optical devices, by virtue of their lightweight and impact resistance, , have attracted significant interest and present a rapid development trajectory toward broad applications including electronic, − light-emitting, , and energy-saving equipment. − However, most existing polymer optical devices manufactured using the traditional method suffered from a number of intrinsic drawbacks because of the molten flow process. , Particularly, the inevitable issue of birefringence and optical distortion due to the anisotropy of the polymer molecular chain , would decrease the imaging quality to a great extent, which enormously limits the applications of polymers in precision optical devices, such as astronaut helmets and telephoto lens. However, to date, the anisotropy of polymer molecular chains has just been slightly reduced by optimizing process parameters or using auxiliary external fields , (electric field, magnetic field, vibration field, etc.…”