Morphology in Blends of a Thermotropic Liquid Crystalline Polymer and Polypropylene
-
E. A. Sabol
Abstract
By monitoring the development of morphology a novel dual extrusion process from the point that the thermotropic liquid crystalline polymer (TLCP) stream meets the matrix material to the final drawn strand, a clear mechanism for the development of the TLCP reinforcement is presented. It was found that under appropriate mixing configurations the fibrillar TLCP morphology seen in strands produced from this method originate at the onset of mixing in the phase distribution system and are subsequently refined as the melt passes through the static mixing elements. The axially continuous morphology seen at the entrance of the die is maintained and further developed as the blend passes through the die and is drawn. In contrast, strands produced using the single extruder blending or the dual extrusion method with excessive mixing produce a droplet morphology prior to the die. At a very low concentration of TLCP, the droplets are too small and well dispersed to sufficiently coalesce and deform into fibrils in the elongational flow field of the die and drawing process. These phenomena result in an undesirable morphology for self reinforcement which clearly has been seen in the measured mechanical properties of the strands.
© 1995, Carl Hanser Verlag, Munich
Articles in the same Issue
- Contents
- Contents
- Editorial
- Fourteenth in a Series: Pomini SpA: Dynamic International Machinery Manufacturer
- Internal Mixers
- Non-isothermal Dispersive Flow of a Rubber Mixture Inside an Internal Rotor Mixer
- Screw Extrusion/Continuous Mixing
- Solids Conveying and Melting in a Starve Fed Self-wiping Co-rotating Twin Screw Extruder
- Modeling the Residence Time Distribution of a Non-Intermeshing Twin Screw Extruder
- Mixing Ring
- Morphology in Blends of a Thermotropic Liquid Crystalline Polymer and Polypropylene
- Die Extrusion
- Mechanical Effects in Extrusion: Slit Dies
- Fibers and Films
- Relationship of Stresses in Blown-film Processes
- Molding
- Modelling and Experiments of Squeezing Flow of Polymer Melts
- Crystallization Behavior of Carbon Fiber Reinforced Polyamides (I) Dynamic and Isothermal Crystallization
- Structures and Properties of Injection Moldings of β-Crystal Nucleator-Added Polypropylenes
- Forging
- Numerical Simulation of Polymer Forging
- Rapid Communication of Recent Advances
- Unstable Gas Penetrations in Symmetrical Rib Channels During Gas-assisted Injection Molding
Articles in the same Issue
- Contents
- Contents
- Editorial
- Fourteenth in a Series: Pomini SpA: Dynamic International Machinery Manufacturer
- Internal Mixers
- Non-isothermal Dispersive Flow of a Rubber Mixture Inside an Internal Rotor Mixer
- Screw Extrusion/Continuous Mixing
- Solids Conveying and Melting in a Starve Fed Self-wiping Co-rotating Twin Screw Extruder
- Modeling the Residence Time Distribution of a Non-Intermeshing Twin Screw Extruder
- Mixing Ring
- Morphology in Blends of a Thermotropic Liquid Crystalline Polymer and Polypropylene
- Die Extrusion
- Mechanical Effects in Extrusion: Slit Dies
- Fibers and Films
- Relationship of Stresses in Blown-film Processes
- Molding
- Modelling and Experiments of Squeezing Flow of Polymer Melts
- Crystallization Behavior of Carbon Fiber Reinforced Polyamides (I) Dynamic and Isothermal Crystallization
- Structures and Properties of Injection Moldings of β-Crystal Nucleator-Added Polypropylenes
- Forging
- Numerical Simulation of Polymer Forging
- Rapid Communication of Recent Advances
- Unstable Gas Penetrations in Symmetrical Rib Channels During Gas-assisted Injection Molding
