Optical properties of polycarbonate

Structure and Crystallinity. The mechanical—optical properties of polycarbonates are those common to amorphous polymers. The polymer may be crystallized to some degree by prolonged heating at elevated temperature (8 d at 180°C) (16), or by immersion ia acetone (qv). Powdered amorphous powder appears to dissolve partially ia acetone, initially becoming sticky, then hardening and becoming much less soluble as it crystallizes. Enhanced crystallization of polycarbonate can also be caused by the presence of sodium phenoxide end groups (17). 

Gunes, l.S. and Ersoy, O.G. (2006) Effects of injection molding processing parameters on appearance related optical properties of polycarbonate. J. Polym. Eng., 26, 743. 

Structure and Crystallinity. The mechanical-optical properties of polycarbonates are those common to amorphous polymers. The polymer may be... 

The effects of replication and molecular orientation on optical properties of polycarbonates (PC) injection molded parts with microscopic v-groove features have been investigated on various injection molding conditions and different cavity shapes. For optical properties, the luminance of the injection molded parts has been characterized. The mold temperature had significant effect on the replication. The replication is closely related to the optical properties. It was found that the optical properties depended on replication in compared with molecular orientation. 

Optical Properties. The optical properties of a plastic which are important are refraction, transparency, gloss and light transfer. The reader is referred to BS 4618 1972 for precise details on these terms. Table 1.9 gives data on the optical properties of a selection of plastics. Some plastics may be optically clear (e.g. acrylic, cellulosics and ionomers) whereas others may be made transparent. These include epoxy, polycarbonate, polyethylene, polypropylene, polystyrene, polysulphone and PVC. 

A more sophisticated retardation plate is a film consisting of the perpendicular arranged combination of two optical uniaxial materials, e g., uniaxially stretched polycarbonate foil with a homeotropic oriented LC siloxane layer [18]. The purpose of such a foil is the improvement of the optical properties of LC displays, especially the viewing angle dependence of the contrast. 

Comparison of optical density of suspension containing 0.001% of nanocomposite and optical density polycarbonate sample modified with 0.01 % of nanocomposite indicates the proximity of curves character. Thus, the correlation of optical properties of suspensions of nanocomposites and film materials modified with the same nanocomposites is quite possible. 

Duan, 1., Liu, 1., Cornelius, T. W. et al. 2009. Magnetic and optical properties of cobalt nanowires fabricated in polycarbonate ion-track templates. Nuclear Instruments and Methods in Physics Research B 267 2567-2570. 

The transparent resin used commercially includes poly(methyl methacrylate) resin, polystyrene resin, SAN resin, polycarbonate resin, etc. Since these resins have both merits and demerits, their use is Umited. Although polystyrene and SAN have very low impact strength, they are often used as the inexpensive transparent resin that does not demand certain impact strength, such as for toys, stationery, etc., due to their low price. Poly(methyl methacrylate) resin has very low impact strength, as does polystyrene resin or SAN, hut can be used as the optical material for lenses, glass, CDs, etc., due to its excellent optical properties. Although polycarbonate has excellent transparency and excellent optical properties, and can be used for any purpose in view of these properties, its practical use is limited due to its high cost and poor processability. 

Jeon CH, Ryu SH, Chang YW (2003) Optical properties of plasticized polycarbonate. Polym Int 53 153-155... 

Optical properties of polymers are characterized by haze, transparency, and gloss (Villalobos et al., 2005). Transparency increases the aesthetic value of the packaging and is usually desirable as it helps in the identification of the packaged material. However, there are light sensitive products, which do not require transparency to have a longer shelf life. Hence, the level of transparency varies from product to product. Some of transparent packaging plastics are PET, PS, and polycarbonate (PC). 

Effects of Adhesive Structure on Impact Resistance and Optical Properties of Acrylic/Polycarbonate Laminates... 

We began our template synthesis work in 1985 by electrochemically synthesizing the electronically conductive polymer polypyrrole within the pores of a nanoporous polycarbonate filtration membrane [10]. Since then, we [9,11-16] and others [26-35] have explored, in some detail, the electrochemical, electronic, and optical properties of template-synthesized conductive polymers. I review this work in this chapter. Topics discussed include the membranes used to do template synthesis, the electronic properties of template-synthesized conductive polymer fibrils and tubules, and the morphology of the template-synthesized conductive polymers. 

The optical properties of nanocomposites prepared with poly(styrene-maleic anhydride) copolymer coated with alumina nanopartides and polycarbonate as matrix was evaluated by Chandra et al. [8]. The transparendes were compared for samples with 2 mm thick polycarbonate neat resin, the samples of nanocomposites containing 1 and 2 wt% of treated alumina, and a sample containing 2 wt% of untreated alumina. The samples were put on top of a pattern, as shown in Figure 6.3. The sample with 1 wt% of treated alumina was the most transparent among the samples containing nanopartides, even though some haziness could be observed. 

Xing C, Zheng X, Xu L, Jia J, Ren J, Li Y (2014) Toward an optically transparent, antielec-trostatic, and robust polymer composite morphology and properties of polycarbonate/ionic liquid composites. Ind Eng Chem Res 53(11) 4304 311. doi 10.1021/ie404096b... 

Nouh, S. A. and Abutalib, M. M., Effect of fast neutron irradiation on the structural and optical properties of Makrofol DE 1-1 CC polycarbonate, Radiation Effects and Defects in Solids Incorporating Plasma Science and Plasma Technology, 165 (11), 845-856 (2010) DOI 10.1080/10420150.2010.481672. 

The optical properties of DMX2415 are comparable to those of conventional polycarbonate BPA homopolymer. Overall transmission and haze... 

Polycarbonates are an unusual and extremely useful class of polymers. The vast majority of polycarbonates are based on bisphenol A [80-05-7] (BPA) and sold under the trade names Lexan (GE), Makrolon (Bayer), CaUbre (Dow), and Panlite (Idemitsu). BPA polycarbonates [25037-45-0] having glass-transition temperatures in the range of 145—155°C, are widely regarded for optical clarity and exceptional impact resistance and ductiUty at room temperature and below. Other properties, such as modulus, dielectric strength, or tensile strength are comparable to other amorphous thermoplastics at similar temperatures below their respective glass-transition temperatures, T. Whereas below their Ts most amorphous polymers are stiff and britde, polycarbonates retain their ductiUty. 

The pace of development has increased with the commercialization of more engineering plastics and high performance plastics that were developed for load-bearing applications, functional products, and products with tailored property distributions. Polycarbonate compact discs, for example, are molded into a very simple shape, but upon characterization reveal a distribution of highly complex optical properties requiring extremely tight dimension and tolerance controls (3,223). 

J. Katajisto, M. Linnolahti, and T.A. Pakkanen, Effect of branching of cyclo-olefin copolymers and polycarbonate polymers on mechanical and optical properties Ab initio and molecular simulation study, /. Mol. Struct., 758(2-3) 189-194, 2006. 

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