ABSTRACT
The development of volume phase gratings written by two-wave-mixing in glass-like polymer storage materials based on poly (methylmethacrylate) and its thermostable derivative (copolymer with acrylic acid) with distributed phenanthrenequinone is investigated experimentally and theoretically. The maximal diffraction efficiency is considered in dependence on the grating period. The redistribution processes of the molecules are described with a one-dimensional diffusion model yielding the existence of a non-local response in the photopolymer layer, and the corresponding non-local response length of phenanthrenequinone is found experimentally.
Subject(s)
Computer-Aided Design , Glass/chemistry , Models, Theoretical , Phenanthrenes/chemistry , Polymers/chemistry , Polymethyl Methacrylate/chemistry , Refractometry/methods , Computer Simulation , Light , Scattering, RadiationABSTRACT
We investigated the contribution of the absorption and phase gratings to the total diffraction efficiency of volume holographic gratings written in glass-like polymer recording materials based on poly(methyl methacrylate) and its thermostable derivative (copolymer with acrylic acid) with distributed phenanthrenequinone. The typical maximal diffraction efficiency was 0.5%-2.0% for the absorption grating and 22-32% for the phase grating. The modulation of the absorption coefficient varied between 10 cm(-1) and 100 cm(-1) and the modulation of the refractive index was about 10(-4)-10(-3).
Subject(s)
Acrylic Resins/chemistry , Glass/chemistry , Holography/methods , Information Storage and Retrieval/methods , Polymethyl Methacrylate/chemistry , Refractometry/methodsABSTRACT
A possibility of poly-D,L-lactide modification by multiwall carbon nanotubes (MWCNT) has been shown. MWCNT were prepared from methane-air mixture upon atmospheric pressure without catalyst on high voltage atmospheric pressure discharge plasma set-up. According to scanning and transmission electronic microscope data carbon nanotubes diameters were within 12-60 nm. Quantities of MWCNT incorporated did not exceed 0.5%. Nanocomposites were obtained by sonification of mixture of a poly-D,L-lactide solution in chloroform and MWCNT followed by film casting on glass substrates. Tensile strength and thermomechanical properties of the dried composite films were investigated. Introduction of MWCNT into poly-D,L-lactide has been shown to cause the enhanced polymer stability to thermal oxidative destruction. Taking into account the results obtained one could anticipate that implants from nanocomposites of poly-D,L-lactide with MWCNT would be dispersed in a living organism more slowly as compared to implants from pure poly-D,L-lactide without additives.
Subject(s)
Biocompatible Materials/chemistry , Nanotubes, Carbon/chemistry , Nanotubes, Carbon/ultrastructure , Polyesters/chemistry , Materials Testing , Particle Size , TemperatureABSTRACT
A possibility to improve the thermal properties of holographic gratings in a photosensitive system based on polymethylmethacrylate (PMMA) and to enhance simultaneously the adhesion of the photopolymer to soda-lime glass is demonstrated. The modified PMMA was prepared by radical copolymerisation of methylmethacrylate (MMA) with acrylic acid (AA). Polymer films deposited from samples of the copolymer of MMA with AA containing 9,10-phenanthrenequinone additives were used as a photosensitive material for the recording of holographic gratings. It is possible to generate gratings that are thermally stable up to 200 masculineC using this modified PMMA. Dynamic thermogravimetry, differential thermal analysis and thermal mechanic analyses were used to determine the dependence of the thermal stability of the modified PMMA on the composition and the structure of its macromolecules.
