WLF Multi-Scale Simulation of Polymer Processing Kathryn Garnavish, David Kazmer, William Rousseau, & Yingrui Shang University of Massachusetts Lowell ACKNOWLEDGEMENT: This research has been sponsored by the National Science Foundation under DMI Research Goal: Research Tasks: Nano-Scale Investigation: Conventional (Continuum) Approach: Continuum Models Consititutive Models ◦Viscosity◦Compressibility◦Viscoelasticity◦Relaxation◦Mass ◦Momentum ◦Heat Optical Media ◦Birefringence Atomistic Modeling of Heat Transfer Atomistic Modeling of Wall Slip Atomistic Modeling of Rheology Publications: Kathryn Elise Garnavish, An Investigation into Hesitation Defects from Oscillating Flows, Univ. of Mass. Lowell, Dept. Plastics Engineering, William Rousseau, Effect of Shear Stress and Velocity Profile Development on Flow Bore Wall Slip, Univ. of Mass. Lowell, Dept. Plastics Engineering, Bingfeng Fan and David Kazmer, Low Temperature Modeling of the Time- Temperature Shift Factor for Polycarbonate, Submitted to Advances in Polymer Technology. ◦Boltzmann Transport Equation ◦Modified Bose-Einstein distribution to estimate Q=f(stress, compatibility,…) ◦Wall slip condition characterized on meso-scale ◦On atomistic level, compare molecular strain to wall adhesive forces < Structural change of the microphase of ABA tri block polymers under elongation. ◦Incorporation of MD simulation for rheological development References:  B. Fan, D. O. Kazmer, W.C. Bushko, R. P. Thierault, A. J. Poslinski, Birefringence Prediction of Optical Media, Polymer Engineering & Science, v. 44, n. 4, April, 2004, p  A.N. Smith and P. M. Norris, Microscale Heat Transfer, Chapter 18 of Heat Transfer Handbook, eds. A. Bejan and A. D., Kraus, John Wiley & Sons,  K. S. Narayan* and A. A. Alagiriswamy, R. J. Spry, DC Transport Studies of poly(benzimida-zobenzophenanthroline) a ladder-type polymer, Physical Review B, v. 59, n. 15, p ,  Fritch, L.W., ABS Cavity Flow – Surface Orientation and Appearance Phenomena Related to the Melt Front, SPE Technical Papers, Vol. 21, 1979, pp  J. S. Bergström and M. C. Boyce, Deformation of Elastomeric Networks: Relation between Molecular Level Deformation and Classical Statistical Mechanics Models of Rubber Elasticity, Macromoleclues, Vol. 32, pp ,  S. H. Anastasiadis and S. G. Hatzikiriakos, The Work of Adhesion of Polymer/Wall Interfaces and the Onset of Wall Slip, J. Rheol., v. 42, n. 4, p ,  M. Doi, Challenges in polymer physics, Pure Appl. Chem., Vol. 75, No. 10, pp. 1395–1402,        Develop and validate a multi-scale polymer processing simulation for concurrent engineering design and manufacturing process development  Develop & validate continuum polymer processing simulation with non-Newtonian, non-isothermal, compressible flow, and thermoviscoelasticity  Literature review of atomistic modeling of boundary conditions  Specification of performance measures and end-use requirements  Implement atomistic heat transfer boundary conditions (2005/06)  Implement atomistic wall slip boundary conditions (2005/06)  Implement molecular dynamic simulation for rheological development (2006/07)  Validate against molding and extrusion processes (2006/07)  Improve & define future work (2007/08)