New Microlayer and Nanolayer Polymer Composites
Abstract
The highlights of this period are centered around the development of polymer nanolayer systems by a novel continuous coextrusion method. Nanolayers ranging in thickness between 5 rim to 500 nm have been manufactured using inexpensive polymeric materials such as polystyrene, polystryene acrylonitrile copolymers, polypropylene, polyethylene, polycarbonate and polymethylmethacrylate. Two and three component systems have been made from various combinations of these polymers. In particular, the morphology of polypropylene has been drastically changed from a routine spherilitic alpha - form structure to a discoidal meso-form structure by just decreasing the layer thickness to nano dimensions. High density polyethylene has been totally changed to a 'shish-kabab' structure due to the fact that the nano-layer thickness is less than the radius of gyration of the polymer macromolecule. When oriented, this novel crystalline morphology appeared as extended chain fibrillar crystals imbedded in polystyrene acting as the continuous phase in a nanocomposite structure. Recently, we have started to develop nano-systems with anisotropic electrical and mechanical properties. Also, gradient and vertical layer structures are being considered. In the last few weeks we have actually succeeded in creating a vertical composite with highly anisotropic mechanical properties composed of polystyrene and a styrene-butadiene block copolymer.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1999
- Accession Number
- ADA395803
Entities
People
- Anne Hiltner
- Eric Baer
Organizations
- Case Western Reserve University