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Showing 1 to 20 of 26 for “"Liquid Crystalline Polymer"”.
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Reclamation and Reprocessing of Thermotropic Liquid Crystalline Polymer from Composites of Polypropylene Reinforced with Liquid Crystalline Polymer
… considerable interest in the use of thermotropic liquid crystalline polymers (TLCPs) to reinforce thermoplastic materials. In a novel process developed by Baird and coworkers, wholly thermoplastic composites are produced via a patented, dual extrusion process. This unique process yields a fiber …
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In situ composites of compatibilized polypropylene/liquid crystalline polymer blends
Methods of processing polypropylene (PP)/ liquid crystalline polymer blends to obtain high mechanical properties from injection molded samples were investigated in this dissertation. Three liquid crystalline polymers (LCPs), two liquid crystalline (LC) copolyesters and one LC poly(ester-amide), …
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The in situ generation of liquid crystalline polymer reinforcements in thermoplastics
… properties of thermoplastics by blending with liquid crystalline polymers (LCPs). Injection molding and sheet extrusion studies of blends of poly(ethylene terephthalate) (PET) with several LCPs were conducted with an emphasis on blends containing 50 wt % or less of the LCP. It was seen that …
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Processing of composite fibers based on polypropylene and a thermotropic liquid crystalline polymer
… reinforced with Vectra B950 (VB), a thermotropic liquid crystalline polymer (TLCP), in two novel fiber spinning processes. In one process, a single VB melt stream was surrounded by a sheath of PP in a manner comparable to a wire coating process just prior to melt spinning to generate fibers …
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Generation of Recyclable Liquid Crystalline Polymer Reinforced Composites for Use in Conventional and Additive Manufacturing Processes
… with higher recyclability. Thermotropic liquid crystalline polymers (TLCPs) are high-performance engineering thermoplastics, which have comparable mechanical performance to that of glass fiber. The TLCP reinforced composites, called in situ composites, can form the reinforcing TLCP …
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Generation of Thermotropic Liquid Crystalline Polymer (TLCP)-Thermoplastic Composite Filaments and Their Processing in Fused Filament Fabrication (FFF)
… used to improve the physical properties of polymeric matrices. However, the blending methods lead to fiber breakage, preventing generation of long fiber reinforced filaments essential for printing load-bearing components. Our approach to improve tensile properties of the printed parts was to …
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Polymer blends formed by the solid state mechanical alloying process
… describes the use of the MA process to form polymer blends. Until recently there has been no published work discussing the possibility of using this technique with polymers. This research lays the ground work for using the MA process to produce polymer blends by comparing this technique to …
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Multiscale simulation of viscoelastic flows : applications to kinetic theory models of polymer melts and liquid crystalline polymers
… the dynamics and molecular configurations of polymer molecules is important for efficient process design and novel product development. Much research has been focused on combining molecular simulations and traditional fluid mechanics computations to simulate the behavior of polymeric liquids …
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The Effects of Processing Conditions on Thermoplastic Prototypes Reinforced with Thermotropic Liquid Crystalline Polymers
… strands reinforced with continuous thermotropic liquid crystalline polymer (TLCP) fibrils were generated in a novel dual extruder process. Strands were then re-extruded to form short fiber composite monofilaments that were used as feed stock in the FDM 1600 rapid prototyping system. Prototypes …
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An investigation of the effects of shearfree deformation and the role of miscibility on the structure and properties of in situ thermoplastic composites
… properties and morphology of thermotropic liquid crystalline polymer blends were investigated in this part of the work. Blends of an immiscible (Vectra A900) and partially miscible (HX1000) thermotropic liquid crystalline polymer (TLCP) with a polyetherimide (PEI) were used in the …
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Experimental studies and modeling of mechanical properties and morphologies of in situ polymer composites
… of poly(ethylene terephthalate) (PET)/ liquid crystalline polymer (LCP) blends. Simulations of the injection molded blends at various process conditions were performed using CMOLD. In order to determine the effect of the processing parameters on the deformation of the LCP domains during …
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Towards improved simulations of self-organising molecular materials
… tested for single site systems and a multipedal liquid crystalline molecule, using conventional molecular dynamics simulations. It is used also to map out an approximate phase diagram for a main chain liquid crystalline polymer as a function of the volume fraction of the mesogenic unit; and to …
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Injection Molding of Pregenerated Microcomposites
… as the matrix and HX1000 as the thermotropic liquid crystalline polymer (TLCP). Several factors were examined to maximize the mechanical properties of these composites, including injection molding temperature, matrix viscosity, and nozzle tip exit diameter. In addition, concentrated strands of …
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Liquid crystalline multi-block copolymers
Lyotropic and thermotropic high strength liquid crystalline polymers have become an important area of research and development in polymeric, high performance materials. These materials have afforded excellent high temperature stability and high strength in the oriented direction, but not in the …
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New functional polymers for sensors, smart materials and solar cells
Organic polymers can be used as the active component of sensors, smart materials, chemical-delivery systems and the active layer of solar cells. The rational design and modification of the chemical structure of polymers has enabled control over their properties and morphology, leading to the …
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Linking the Rheological Behavior to the Processing of Thermotropic Liquid Crystalline Polymers in the Super-cooled State
Thermotropic liquid crystalline polymers (TLCPs) have attracted great interest because of the combination of their promising properties, which includes high stiffness and strength, excellent processability, and outstanding chemical resistance. TLCPs exhibit inherently low viscosity relative to many …
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Textured fluids
… The first fluid considered in this work was a liquid crystalline polymer consisting of isotropic and anisotropic solutions of poly-p-phenyleneterephthalamide (PPT) in sulfuric acid. The second textured fluid considered in this work was an immiscible polymer blend consisting of poly(ethylene …
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The rheology and structure of thermotropic liquid crystalline polymers in extensional flow
… measured in order to determine the behavior of liquid crystalline polymer systems and to establish whether this behavior is different from that for isotropic flexible-chain polymer melts and isotropic systems of rodlike polymers. In order to accomplish this a rotary clamp extensional rheometer …
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Synthesis, Characterization, Membrane Fabrication and Gas Transport Behavior of Liquid Crystal Polymer Materials
A variety of liquid crystalline (LC) materials have been examined as potential membrane separation materials. The order present in the LC phases has measurable effects on solute sorption, diffusivity, permeability, and selectivity, and can thus be used to tune the transport and separation of …
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