CHEM 4214 Lecture Notes - Lecture 34: Amorphous Solid, Epoxy, Elastomer
Document Summary
If probe polymer faster than fastest relaxation time, solid behavior if slower than slowest relaxation time, liquid behavior. Multiple relaxation times relaxation of whole chain takes long time relaxation of small segment takes shorter time. No hydrodynamic interactions btwn the beads they interact through the spring, but not through the fluid they"re in. Strong hydrodynamics interaction (nondraining) same tau_seg p = 1,2,,n times unentangled polymer melts (low molecular weight) concentrated polymer solutions if don"t do sum, then same as maxwell modelbut we do sum b/c now have multiple relaxation. If omega is high, then only spring reactsdashpot never participates if omega is very low, only dashpot respondsspring doesn"t participate. If have high mw polymer melt: entanglement restricts the motion of its neighbors low time plateau glassy region transition rubbery plateau terminal region (flow) =relaxation of chain in tube reptation relaxation time. Neighbors act like fixed points then we have a chain going through the objects.
