Unperturbed dimensions of stereoregular polymers.- Reinforcement of rubber by carbon black.- Transformations of phenolic antioxidants and the role of their products in the long-term properties of polyolefins.

Properties of polymers

We demonstrate the continuous tuning of the electronic structure of atomically thin MoS2 on flexible substrates by applying a uniaxial tensile strain. A redshift at a rate of ~70 meV per percent applied strain for direct gap transitions, and at a rate 1.6 times larger for indirect gap transitions, have been determined by absorption and photoluminescence spectroscopy. Our result, in excellent agreement with first principles calculations, demonstrates the potential of twodimensional crystals for applications in flexible electronics and optoelectronics.

Experimental demonstration of continuous electronic structure tuning via strain in atomically thin MoS2

We demonstrate the continuous tuning of the electronic structure of atomically thin MoS2 on flexible substrates by applying a uniaxial tensile strain. A redshift at a rate of ∼70 meV per percent applied strain for direct gap transitions, and at a rate 1.6 times larger for indirect gap transitions, has been determined by absorption and photoluminescence spectroscopy. Our result, in excellent agreement with first principles calculations, demonstrates the potential of two-dimensional crystals for applications in flexible electronics and optoelectronics.

Experimental Demonstration of Continuous Electronic Structure Tuning via Strain in Atomically Thin MoS2

In this report dispersion properties of dierent types of optical polymers are discussed on the base of measured refractive indices and the Cauchy‐Schott approximation. A number of dispersion curves are presented in the visible and near infrared spectral regions between 400 and 1060 nm. A comparison with some optical glasses with similar refraction is performed. The nonlinear dependence of dn=d‚ of polymer materials and test glasses on the wavelength is calculated and analyzed. Normalized dispersion curves at 550 nm and 880 nm are presented to illustrate better the dispersion of the polymers in the considered spectral regions, separately. Abbe numbers are calculated to exhibit the mean and partial dispersion.

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Dispersion Properties of Optical Polymers

Analysis of the dispersion of optical plastic materials

Possible applications of polymer materials in optical systems and devices are defined mainly by their optical properties in terms of refractive indices, transmission, dispersion and thermo-optic coefficients. We have examined more than twenty types of optical plastics including basic, commercial and some new development materials. Detailed measured refractometric data and transmission spectra in the visible and near infrared regions are presented. Variation of refractive indices with temperature is considered to obtain the thermo-optic coefficients. Discussion on dispersion of studied optical polymers and comparison to glass is included on the base of a number of dispersive characteristics and curves.

https://www.tpbin.com/Uploads/Subjects/a80f1ad6-c5be-4687-ad1b-04d721233e26.pdf

Characterization of optical properties of optical polymers

Ten types of American, Japanese, and German optical plastic (OP) materials are examined. The principal OPs are analysed: polymethyl methacrylate, polystyrene, polycarbonate, and styrene acrylonitrile. Refractive indices are measured and calculated for the principal and some new applicable OPs, namely NAS-21 Novacor, CTE-Richardson, Zeonex E48R, Optorez 1330 and Bayer for wavelengths from 435.8 to 1052 nm. A theoretical examination was made for computer modelling of OPs indices using Cauchy's dispersion formula. The dispersion coefficients and Abbe constants are calculated. The OPs indices computed for numerous laser wavelengths 442–1060 nm are presented. A more effective device and technology for the measurement of refractive index of OPs is realized with an accuracy of ±0.001.

Measuring the refractometric characteristics of optical plastics

In this study we investigate the variation of refractive characteristics of optical plastics with temperature in the range of 10 to 50 oC. We have measured the indices of several optical polymers as Optorez 1330, Zeonex E48R, Polymethyl methacrylate, S-low styrene and Bayer by means of the deviation angle method. The obtained refractive index data is presented at five standard spectral lines in the visible region. A decrease of refractive index values with increasing temperature is observed. Dependence on measuring wavelength is also noticed. We have calculated the temperature coefficients of refractive indices of the studied optical plastics. Charts of refractive index of some of the materials versus temperature are presented. Temperature dependence of dispersion curves based on Cauchy-Schott's approximation and Abbe numbers is also considered.

https://iopscience.iop.org/article/10.1088/1742-6596/253/1/012028/pdf

Nina G. Sultanova

Papers

Dispersion Properties of Optical Polymers

Analysis of the dispersion of optical plastic materials

Characterization of optical properties of optical polymers

Measuring the refractometric characteristics of optical plastics

Temperature dependence of refractive characteristics of optical plastics