Rheological and Thermal Characterization of Thermoplastics Filled with Nano-Sized Particles

Addition of nano-sized particles (both clay and carbon nano-tubes) to thermoplastic polymers via melt processing method can improve mechanical, thermal, and electrical properties of the host polymer. It has been shown that the properties improvement is strongly related to dispersion and structure state of the nano-particles which are affected by compounding of the thermoplastic pellets and the processing of the pellets into a final product using injection or compression molding. A reliable testing method is needed to grade the quality of dispersion of the compounded pellets and structure state of the molded part.

• Rheological characterization of polycarbonate filled with carbon nano-tubes
• Rheological characterization of nylon filled with nano-clay particles

Fiber Orientation in Molded Composites

When a chopped fiber reinforced polymer is injection or compression molded, the flow during mold-filling (and packing in injection molding) stage(s) create preferred microstructure in the part.  This may lead to point-to-point variation and anisotropy in the properties of the molded material. Fiber length distribution, fiber orientation distribution, and crystallinity are the three major components of microstructure. Understanding the factors that enhance the development of desired or undesired microstructure is of prime importance to both the material supplier and the molder.  Furthermore, successful prediction of the microstructure using computer simulation can in fact reduce the development time to convert pellets of reinforced thermoplastics to successful products at a minimum time and expense.

• Measurement of fiber orientation in molded parts
• Correlation of fiber orientation to material properties and processing conditions
• Prediction o fiber orientation in molded parts
• Control of fiber orientation in molded parts

PROBLEMS STUDIED IN THE PAST

Rheology of Polymeric and Composite Materials

• Rheological characterization of suspension
• Rheokinetics characterization of thermoset systems
• Rheological characterization of paints

Application of Digital Image Processing to Analysis of Multiphase Systems

• Statistical characterization of suspensions with spherical particles
• Development of a novel technique to determine fiber orientation distribution in composites with chopped fibers
• Identification of fiber types in hybrid composites

Development of New Products and Processes

• Developed composite materials from leather scarps to be used in shoe industry
• Developed an economical process for manufacturing of the composites made of leather scarps

Transport Properties of Composite Materials

• Investigated thermal conductivity measurement techniques for composite materials
• Investigated the electromagnetic wave absorption properties of composite materials
• Investigated heat transfer issues in thermally conductive polymeric composite materials