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Articles 1 - 30 of 99
Full-Text Articles in Engineering
Effect Of Carbon Nanotube On Phase Transitions Of Nematic Liquid Crystals, Hatice Duran, Bruce Gazdecki, Atsushi Yamashita, Thein Kyu
Effect Of Carbon Nanotube On Phase Transitions Of Nematic Liquid Crystals, Hatice Duran, Bruce Gazdecki, Atsushi Yamashita, Thein Kyu
Thein Kyu
Phase diagrams of multiwall carbon nanotube (MWNT)/nematic liquid crystal (E7) and bucky ball (C60)/nematic liquid crystal binary systems were investigated by means of optical microscopy and differential scanning calorimetry (DSC). It was found that the isotropic-nematic phase transition temperature of liquid crystal component is enhanced by MWNT. A chimney type phase diagram occur over a narrow range of 0.1-0.2ball/E7 system did not showed any changes of TNI in the same concentration range. This behavior has been attributed to anisotropic alignment of carbon nanotubes and liquid crystal molecules, which is entropic in origin.
Polyolefin Composites, Thein Kyu
Conductive Behaviour In Relation To Domain Morphology And Phase Diagram Of Nafion/Poly(Vinylidene Co Triflouoroethylene) Blends, Nadzrinahamin Nazir, Namil Kim, Wilder Iglesias, Antal Jakli, Thein Kyu
Conductive Behaviour In Relation To Domain Morphology And Phase Diagram Of Nafion/Poly(Vinylidene Co Triflouoroethylene) Blends, Nadzrinahamin Nazir, Namil Kim, Wilder Iglesias, Antal Jakli, Thein Kyu
Thein Kyu
Electron and proton conductive properties of Nafion/poly(vinylidene fluroride)-co- trifluoroethylene (PVDF-TrFE) blends were investigated in relation to domain morphology guided by phase diagram using differential scanning calorimetry, polarized optical microscopy, and AC impedance analyzers. A theoretical phase diagram was established by self-consistently solving the combined free energy density of FloryeHuggins theory for liquid-liquid demixing and the phase field theory for crystal solidification. Nafion/PVDF-TrFE blends revealed an hourglass type phase diagram, consisted of single phase crystal (Cr1), liquid þ liquid (L1 þ L2) and crystal þ liquid (Cr1 þ L2) coexistence regions. Guided by the phase diagram, the co-continuous or dispersed droplet …
Influence Of Acrylate Arm Topology On Phase Diagrams Of Mixtures Of Multi-Arm Acrylate Photo-Curative Monomers And Nematic Liquid Crystals, Scott Meng, Hatice Duran, Thein Kyu
Influence Of Acrylate Arm Topology On Phase Diagrams Of Mixtures Of Multi-Arm Acrylate Photo-Curative Monomers And Nematic Liquid Crystals, Scott Meng, Hatice Duran, Thein Kyu
Thein Kyu
Phase equilibria of binary mixtures of liquid crystal and multiarm star acrylate derivatives have been established as a function of the number of acrylate arms by means of cloud point determination. Equilibrium phase diagrams of liquid crystal/multiarm acrylate derivatives have been calculated self-consistently in the framework of combined Flory−Huggins free energy of liquid−liquid demixing and Maier−Saupe free energy of nematic ordering. It was found experimentally that the phase diagram of the branched/star molecule/solvent shifts to elevated temperatures with an increasing number of acrylate arms. This movement of the coexistence line is attributed to the architectural effect contributing to the athermal …
Melt-Processable, Toughened, Transparent Blends Of Pc/Pmma, Thein Kyu
Melt-Processable, Toughened, Transparent Blends Of Pc/Pmma, Thein Kyu
Thein Kyu
No abstract provided.
Experimental And Theoretical Investigations Of Porous Structure Formation In Electrospun Fibers, Pratyush Dayal, Jing Liu, Satish Kumar, Thein Kyu
Experimental And Theoretical Investigations Of Porous Structure Formation In Electrospun Fibers, Pratyush Dayal, Jing Liu, Satish Kumar, Thein Kyu
Thein Kyu
The development of internal microstructure in electrospun fibers has been investigated both experimentally and theoretically. Various morphologies such as tubes, beads, and porous structures have been observed experimentally during electrospinning from amorphous polymer solutions such as poly(methyl methacrylate)/methylene chloride and poly(styrene)/tetrahydrofuran. The dynamics of electrospinning is modeled based on multiple virtual strands of beads connected by Maxwell's elements in a cylindrical coordinate system. Concurrently, spatiotemporal growth of the porous structure is calculated in the framework of Cahn−Hilliard time-evolution equation under the quasi steady state assumption coupled with the solvent evaporation rate equation. The coarse-grain simulation reveals the real-time formation of …
Role Of Crystal-Amorphous Interaction On Phase Equilibria Of Crystal/Amorphous Polymer Blends, Rushikesh Matkar, Thein Kyu
Role Of Crystal-Amorphous Interaction On Phase Equilibria Of Crystal/Amorphous Polymer Blends, Rushikesh Matkar, Thein Kyu
Thein Kyu
A self-consistent theory has been developed for determination of phase diagrams of a crystalline polymer solution. Although the original Flory diluent theory captures the liquidus line, the theory is incapable of accounting for the solidus line due to the inherent assumption of complete immiscibility of solvent in the solid crystal. The present theory considers all possible interactions involving amorphous-amorphous and crystal-amorphous interactions. The self-consistent solutions predict various phase diagrams involving liquid-liquid, pure solid, and liquid-solid coexistence regions bound by liquidus and solidus lines. In the limit of complete insolubility of solvent in neat solid crystal, the original Flory diluent theory …
Single Phase Blends Of Polycarbonate And Polmethyl Methacrylate, Thein Kyu, Jeanne Saldanha
Single Phase Blends Of Polycarbonate And Polmethyl Methacrylate, Thein Kyu, Jeanne Saldanha
Thein Kyu
Clear, transparent, single phase blends of polycarbonate and a polyalkyl methacrylate in which the alkyl radical contains from 1 to about 10 carbon atoms, and in which the polycarbonate and the polyalkyl methacrylate are miscible in all proportions are obtained. Polymethyl methacrylate (PMMA) is the preferred polyalkyl methacrylate. These blends may be prepared by dissolving the two polymers in a mutual solvent having a boiling point of at least about 30° C. and evaporating the solvent at a temperature of from about 30° C. to the boiling point of the solvent. The preferred evaporation temperatures are from about 45° C. …
Morphology Development In Main-Chain Liquid Crystalline Polymer Fibers During Solvent Evaporation, Pratyush Dayal, Andrew Guenthner, Thein Kyu
Morphology Development In Main-Chain Liquid Crystalline Polymer Fibers During Solvent Evaporation, Pratyush Dayal, Andrew Guenthner, Thein Kyu
Thein Kyu
A nonequilibrium thermodynamic approach has been developed for describing the emergence of fiber morphologies from a liquid crystalline polymer solution undergoing solvent evaporation, including fibrillar structures, concentric rings, and spiral structures. We utilized Matsuyama–Kato free energy for main-chain liquid crystalline polymer (MCLCP) solutions, which is an extension of Maier–Saupe theory for nematic ordering and incorporates a chain-stiffening, combined with Flory-Huggins free energy of mixing. Temporal evolution of the concentration and nematic order parameters pertaining to the above free energy density of liquid crystalline polymer solution was simulated in the context of time-dependent Ginzburg–Landau theory coupled with the solvent evaporation rate …
Asymmetric Membranes Formed By Coagulation Induced Phase Separation Of Poly(Vinyl Pyrrolidone)/Poly(Ether Sulfone)/Genistein Blends, Teng Chang, Chandrasekaran Neelakandan, Thein Kyu, Yu-Tsan Tseng, Linda Define, Thomas Alexander
Asymmetric Membranes Formed By Coagulation Induced Phase Separation Of Poly(Vinyl Pyrrolidone)/Poly(Ether Sulfone)/Genistein Blends, Teng Chang, Chandrasekaran Neelakandan, Thein Kyu, Yu-Tsan Tseng, Linda Define, Thomas Alexander
Thein Kyu
Development of asymmetric channel morphology driven by coagulation-induced phase separation of genistein (G) modified poly(ether sulfone)/poly(vinyl pyrrolidone) (PES/PVP) blends has been examined in relation to their miscibility phase diagram. PES/G pairs turned out to be miscible in the amorphous state, whereas solid–liquid phase separation occurred at high genistein compositions. The solid–liquid phase diagram involving the liquidus and solidus lines were computed self-consistently in the framework of the combined free energy of Flory-Huggins for liquid–liquid phase separation and phase field free energy for crystal solidification. The ternary phase diagram of PES/PVP/G blends was subsequently established that consisted of various coexistence regions. …
In Vitro Evaluation Of Anti-Oxidant And Anti Inflammatory Properties Of Genistein Modified Hemodialysis Membranes, Chandrasekaran Neelakandan, Teng Chang, Thomas Alexander, Linda Define, Michelle Evancho-Chapman, Thein Kyu
In Vitro Evaluation Of Anti-Oxidant And Anti Inflammatory Properties Of Genistein Modified Hemodialysis Membranes, Chandrasekaran Neelakandan, Teng Chang, Thomas Alexander, Linda Define, Michelle Evancho-Chapman, Thein Kyu
Thein Kyu
Genistein-modified poly(amide):poly(vinyl pyrrolidone) (PA:PVP/G) hemodialysis membranes have been fabricated by coagulation via solvent (dimethyl sulfoxide, DMSO)/nonsolvent (water) exchange. The antioxidant and anti-inflammatory properties of the unmodified PA:PVP membranes were evaluated in vitro using human blood. It was found that these unmodified PA:PVP membranes were noncytotoxic to peripheral blood mononuclear cells (PBMC) but raised intracellular reactive oxygen species (ROS) levels. Pure genistein (in DMSO solution) was not only nontoxic to PBMC, but also suppressed the ROS levels in a manner dependent on genistein dosage. A similar dose-dependent suppression of ROS was found in genistein-modified PA (i.e., PA/G) membranes. However, the PVP …
Liquid Crystalline Polymer Systems: Tech. Advances, Thein Kyu
Liquid Crystalline Polymer Systems: Tech. Advances, Thein Kyu
Thein Kyu
No abstract provided.
Preparation, Characterization, And Physical Properties Of Multiwall Carbon Nanotube/Elastomer Composites, Leon Perez, Manuel Zuluaga, Thein Kyu, James Mark, Betty Lopez
Preparation, Characterization, And Physical Properties Of Multiwall Carbon Nanotube/Elastomer Composites, Leon Perez, Manuel Zuluaga, Thein Kyu, James Mark, Betty Lopez
Thein Kyu
The present article describes preparation, characterization, and physical properties of nanoparticles-filled composites consisting of multiwall carbon nanotubes (MWCNT) and styrene-butadiene rubber and nitrile- butadiene rubber. The reinforcing MWCNT fillers were synthesized by chemical vapor deposition on iron and cobalt catalysts supported by calcium carbonate substrates. These MWCNT were further treated with nitric acid to produce hydroxyl and carbonyl functional groups on the carbon nanotubes (CNT) surfaces. Of particular importance is that these functionalized CNTs were found to exert profound influence on the elastomeric matrices, particularly the vulcanization activation energy, resistance to solvent swelling, enhanced glass transition temperature, and improved storage …
Phase Equilibria And Phase Separation Dynamics In A Polymer Composite Containing A Main-Chain Liquid Crystalline Polymer, Do Kim, Thein Kyu, Takeji Hashimoto
Phase Equilibria And Phase Separation Dynamics In A Polymer Composite Containing A Main-Chain Liquid Crystalline Polymer, Do Kim, Thein Kyu, Takeji Hashimoto
Thein Kyu
Various topological phase diagrams of blends of main-chain liquid crystalline polymer (MCLCP) and flexible polymer have been established theoretically in the framework of Matsuyama–Kato theory by combining Flory–Huggins (FH) free energy for isotropic mixing, Maier–Saupe (MS) free energy for nematic ordering in the constituent MCLCP, and free energy pertaining to polymer chain-rigidity. As a scouting study, various phase diagrams of binary flexible polymer blends have been solved self-consistently that reveal a combined lower critical solution temperature (LCST) and upper critical solution temperature (UCST), including an hourglass phase diagram. The calculated phase diagrams exhibit liquidus and solidus lines along with a …
Crystal Liquid Crystal Phase Diagrams, Thein Kyu
Eutectic Mesophase Transitions And Induced Crystalline Phase In Mixtures Of Hexagonal Columnar Liquid Crystal And Mesogenic Diacrylate, Tsang-Min Huang, Raisa Talroze, Thein Kyu
Eutectic Mesophase Transitions And Induced Crystalline Phase In Mixtures Of Hexagonal Columnar Liquid Crystal And Mesogenic Diacrylate, Tsang-Min Huang, Raisa Talroze, Thein Kyu
Thein Kyu
Eutectic behavior and the induced crystalline phase in mixtures of hexagonal columnar liquid crystal, 2, 3, 6, 7, 10, 11-hexakis-(pentyloxy) triphenylene (HPTP)/reactive mesogenic diacrylate monomer, 4-(3-acryloyloxypropyloxy)-benzoic acid 2-methyl-1, 4-phenylene ester (RM257) have been investigated both experimentally and theoretically. To determine the theoretical phase boundaries, we combined the free energy of Flory−Huggins free energy for liquid−liquid demixing, Maier−Saupe free energy of nematic ordering, and Chandrasekhar−Clark free energy of hexagonal ordering. The calculated phase diagram of the HPTP/RM257 blend is essentially of a eutectic type that consists of isotropic (I), nematic (N), and hexagonal columnar (Colh) regions, and nematic + isotropic (N+I), …
Incorporation Of Hyperbranched Supramolecules Into Nafion Ionomer Domains Through Impregnation And In-Situ Photopolymerization, Nadzrinahamin Nazir, Thein Kyu, Anna Reinsel, Matthew Espe, Mami Nosaka, Hiruto Kudo, Tadatomi Nishikubo
Incorporation Of Hyperbranched Supramolecules Into Nafion Ionomer Domains Through Impregnation And In-Situ Photopolymerization, Nadzrinahamin Nazir, Thein Kyu, Anna Reinsel, Matthew Espe, Mami Nosaka, Hiruto Kudo, Tadatomi Nishikubo
Thein Kyu
Nafion membranes were impregnated with photocurable supramolecules, viz., hyperbranched polyester having pendant functional carboxylic acid groups (HBPEAc-COOH) by swelling in methanol and subsequently photocured in-situ after drying. Structure-property relationships of the HBPEAc-COOH impregnated Nafion membranes were analyzed on the basis of Fourier transform infrared (FTIR) spectroscopy, solid-state nuclear magnetic resonance (SSNMR) and dynamic mechanical analysis (DMA). FTIR and SSNMR investigations revealed that about 7 wt % of HBPEAc-COOH was actually incorporated into the ionic domains of Nafion. The FTIR study suggests possible complexation via inter-species hydrogen bonding between the carboxylic groups of HBPEAc-COOH and the sulfonate groups of Nafion. The …
Experimental And Theoretical Investigations Of Porous Structure Formation In Electrospun Fibers, Thein Kyu
Experimental And Theoretical Investigations Of Porous Structure Formation In Electrospun Fibers, Thein Kyu
Thein Kyu
The development of internal microstructure in electrospun fibers has been investigated both experimentally and theoretically. Various morphologies such as tubes, beads, and porous structures have been observed experimentally during electrospinning from amorphous polymer solutions such as poly(methyl methacrylate)/methylene chloride and poly(styrene)/tetrahydrofuran. The dynamics of electrospinning is modeled based on multiple virtual strands of beads connected by Maxwell's elements in a cylindrical coordinate system. Concurrently, spatiotemporal growth of the porous structure is calculated in the framework of Cahn−Hilliard time-evolution equation under the quasi steady state assumption coupled with the solvent evaporation rate equation. The coarse-grain simulation reveals the real-time formation of …
Effects Of Trans-Cis Photoisomerization On Phase Equilibria And Phase Transition Of Liquid Crystalline Azobenzene Chromophore And Its Blends With Mesogenic Diacrylate, N. Kim, Q. Li, Thein Kyu
Effects Of Trans-Cis Photoisomerization On Phase Equilibria And Phase Transition Of Liquid Crystalline Azobenzene Chromophore And Its Blends With Mesogenic Diacrylate, N. Kim, Q. Li, Thein Kyu
Thein Kyu
Photoisomerization-induced phase transition of neat liquid-crystalline azobenzene chromophore (LCAC) and its effect on phase diagrams of its mixtures with reactive mesogenic diacrylate monomer (RM257) have been investigated experimentally and theoretically. Upon irradiation with ultraviolet light, the nematic phase of LCAC transformed to isotropic, while the crystal phase showed corrugated textures on the surface (i.e., ripples). The phase-transition temperatures and corresponding morphologies of the blends have been investigated by means of differential scanning calorimetry and optical microscopy. A theoretical phase diagram of a binary nematic and crystalline system was constructed by self-consistently solving the combined free energies of Flory-Huggins, Maier-Saupe, and …
Experimental Observation And Phase-Field Modeling Of Interface Morphological Transition In Unidirectional Solidification, Thein Kyu
Thein Kyu
No abstract provided.
Dynamics Of Spherulitic Growth In Blends Of Polypropylene Isomers, Rujul Mehta, Thein Kyu
Dynamics Of Spherulitic Growth In Blends Of Polypropylene Isomers, Rujul Mehta, Thein Kyu
Thein Kyu
The spatiotemporal growth of spherulites in blends of isotactic polypropylene (iPP) and atactic polypropylene (aPP) isomers has been investigated theoretically with the time-dependent Ginzburg–Landau equation, which consists of a nonconserved crystal order parameter and a conserved compositional order parameter. In the description of the total free energy, a local free energy density in the form of an asymmetrical double well, signifying the metastability and latent heat of crystallization, is combined with a nonlocal free energy term representing the interface gradient. In addition, the Flory–Huggins free energy for mixing between iPP and aPP isomers has been employed to account for blend …
Collaborative Studies Of Thermo-Oxidative Degradation Of Styrene Isoprene Diblock Copolymer, Scott Meng, S. Kuchanov, Jingli Xu, Thein Kyu
Collaborative Studies Of Thermo-Oxidative Degradation Of Styrene Isoprene Diblock Copolymer, Scott Meng, S. Kuchanov, Jingli Xu, Thein Kyu
Thein Kyu
Mechanisms and dynamics of thermo-oxidative degradation of styrene-co-isoprene (SI) diblock at a temperature above the order–disorder transition temperature, Todt, have been investigated both experimentally and theoretically. The structural development of SI during degradation was monitored by optical microscopy, and the reduction of molecular weight and molecular weight distribution during the degradation was determined by gel permeation chromatography (GPC). The degradation process was modeled in the framework of a kinetic model based on the framework of the Flory principle. The theoretical predictions were compared with the GPC results. Fourier transformed infrared spectroscopy (FTIR) experiment was conducted in situ during the thermo-oxidative …
Effects Of Genistein Modification On Miscibility And Hydrogen Bonding Interactions In Poly(Amide)/Poly(Vinyl Pyrrolidone) Blends And Morphology Development During Coagulation, Chandrasekaran Neelakandan, Thein Kyu
Effects Of Genistein Modification On Miscibility And Hydrogen Bonding Interactions In Poly(Amide)/Poly(Vinyl Pyrrolidone) Blends And Morphology Development During Coagulation, Chandrasekaran Neelakandan, Thein Kyu
Thein Kyu
Miscibility characteristics of poly(amide):poly(vinyl pyrrolidone) (PA:PVP) blends containing a soybean-derived phytochemical called “genistein” have been investigated using differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The occurrence of hydrogen bonding in the binary PA/genistein (PA/G) and PVP/genistein (PVP/G) pairs as well as their ternary blends has been confirmed by Fourier transformed infrared spectroscopy (FTIR). On the basis of DSC and POM data, the morphology phase diagram of PA:PVP/G blends is mapped out, which consisted of various coexistence regions such as isotropic, liquid + liquid, liquid + crystal, liquid + liquid + crystal, and solid crystal regions. Subsequently, PA:PVP membranes …
Reaction Induced Phase Separation In Blends Of Epoxy And Multifunctional Polybutadiene, Thein Kyu
Reaction Induced Phase Separation In Blends Of Epoxy And Multifunctional Polybutadiene, Thein Kyu
Thein Kyu
The phase behavior and separation dynamics have been investigated in blends of diglycidyl ether of bisphenol A (DGEBA), curing agent methylene dianiline (MDA), and a reactive liquid rubber (R45EPI) through application of differential scanning calorimetry (DSC), one- and two-dimensional light scattering, and optical microscopy. DSC analysis indicates that the system consists of three reactions: the self-condensations of DGEBA and R45EPI, as well as a cross-reaction between the two constituents. Observation of the dynamics of the 50/25.4/50 DGEBA/MDA/R45EPI system reveals that an initial phase separation is governed by the dominant self-curing reaction of DGEBA, followed by a phase dissolution characterized by …
Highly Conductive, Completely Amorphous Polymer Electrolyte Membranes Fabricated Through Photo-Polymerization Of Ply(Ethylene Glycoldiacrylate) Containing Solid Plasticizer And Ionic Liquid Mixtures, Thein Kyu
Thein Kyu
No abstract provided.
Miscibility Characterization In Relation To Phase Morphology Of Poly(Ether Sulfone)/Poly(Vinyl Pyrrolidone) Blends Containing A Phytochemical, Chandrasekaran Neelakandan, Thein Kyu
Miscibility Characterization In Relation To Phase Morphology Of Poly(Ether Sulfone)/Poly(Vinyl Pyrrolidone) Blends Containing A Phytochemical, Chandrasekaran Neelakandan, Thein Kyu
Thein Kyu
Miscibility and morphology of poly(ether sulfone)/poly(vinyl pyrrolidone) (PES/PVP) blends containing a crystalline phytochemical called mangiferin were investigated using differential scanning calorimetry (DSC), Fourier transformed infrared spectroscopy (FTIR), and polarized optical microscopy (POM). The binary blends of PES/PVP were found to be completely miscible. However, FTIR experiments revealed no spectral shift that is attributable to the miscibility of the PES/PVP pair, although the occurrence of hydrogen-bonding interactions can be confirmed in binary blends of both PES/mangiferin and PVP/mangiferin. The addition of mangiferin to the PES/PVP blends resulted in liquid-liquid phase separation as well as liquid-solid phase transition. However, the liquid-liquid phase …
Phase Equilibria Of A Mixture Of A Side Chain Liquid Crystalline Polymer And Its Blends With Low Molecular Mass Liquid Crystal, Namil Kim, Jaehyuck Choi, Liang-Chy Chien, Thein Kyu
Phase Equilibria Of A Mixture Of A Side Chain Liquid Crystalline Polymer And Its Blends With Low Molecular Mass Liquid Crystal, Namil Kim, Jaehyuck Choi, Liang-Chy Chien, Thein Kyu
Thein Kyu
A side-chain liquid crystalline polymer based on p-methoxyphenyl-p‘-acryloyloxy benzoate was synthesized for utilization in a polymer dispersed liquid crystal. Phase diagram of the blends of side-chain liquid crystalline polymer and low molecular mass liquid crystal (K21) was established by means of light scattering and differential scanning calorimetry. A theoretical phase diagram was established by self-consistently solving the combined free energy densities of Flory−Huggins, Maier−Saupe, and phase field theory of solidification. The theoretical phase diagram was established to compare with the observed phase diagram of the binary mesogenic mixtures, showing the isotropic, isotropic + nematic (L1 + N2), nematic + nematic …
Impregnation Of Waterwheel Supramolecules As Proton Carrier In Natin Perfluorinated Ionomer Membranes, Thein Kyu
Thein Kyu
No abstract provided.
Photochromism And Photopolymerization Induced Mesophase Transitions In Mixtures Of Spiropyran And Mesogenic Diacrylate, Namil Kim, Harris Lam, Thein Kyu
Photochromism And Photopolymerization Induced Mesophase Transitions In Mixtures Of Spiropyran And Mesogenic Diacrylate, Namil Kim, Harris Lam, Thein Kyu
Thein Kyu
A phase diagram of a binary mixture of photochromic molecule (spiropyran) and mesogenic diacrylate monomer has been established by means of differential scanning calorimetry and polarized optical microscopy. Subsequently, a theoretical phase diagram has been calculated by self-consistently solving the combined Flory−Huggins free energy for isotropic mixing, Maier−Saupe free energy for nematic ordering, and phase field free energy for crystal solidification. The phase diagram thus obtained consists of various coexistence regions involving single-phase crystals, pure nematic, crystal + liquid, crystal + nematic, and crystal + crystal coexistence gaps. Under UV irradiation, both SP and SP/RM257 mixtures showed the lowering trend …
Non-Birefringent Optical Adhesives And Films, Thein Kyu
Non-Birefringent Optical Adhesives And Films, Thein Kyu
Thein Kyu
The invention pertains generally to miscible polymer blends which can be used in optical applications, particularly in liquid crystal displays and optical adhesives, in that they are essentially birefiringence-free. The polymeric blend alloy includes a first polymer having an inherent positive birefringence and a second polymer having an inherent negative birefringence, the first and second polymers being soluble within each other to predefined limits. The polymer blend is an essentially birefringence-free film layer suitable for use in liquid crystal displays which has adequate mechanical properties, such as dimensional stability, permeability to water vapor, scratch-resistance and insensitivity to temperature, in that …