High Performance Macromolecular Material
Abstract
Our early work centered upon microstructure coupling with strong flows, which include fiber spinning arid general extensional flows. These remain the most successful flow-processing regimes for high-performance materials because hydrodynamics dominates the microscopic physics. In essence, most commercial high-performance polymers are processed through fiber spinning, following Nature and spider silk, which is still pound-for-pound the toughest liquid crystalline polymer. Our work has contributed toward the derivation of models, their analysis and computation, leading to quantitative models for steady, robust, and controllable microstructure alignment in extension-dominated liquid crystalline polymer flow processes 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 93. The current major efforts in materials design are toward fabricating 2 and 3 dimensional products, from thin films to solid structures. The highly successful fiber processes are not scalable: one has to weave volumes of fibers to make higher dimensional products, and then one only has homogenized averages of anisotropic fiber properties, where the averages must arise from mixing filaments. So one has to leave the 1 dimensional world of fibers and study either film flows or general mold-filling type flows. Such processes are dominated by shear components, which are weak flows marked by linear particle trajectories as opposed to exponential streamlines of extension-dominated flows.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 2002
- Accession Number
- ADA414177
Entities
People
- M. G. Forest
Organizations
- University of North Carolina at Chapel Hill