Polymers Research Group Technical Report Series
This series includes technical reports prepared by faculty, students and staff who are affiliated with the Polymers Research Group in the Department of Chemical Engineering at Queen’s University. These reports are intended to furnish rapid communication to persons who have an active interest in the subject matter and to stimulate comment, including corrections of possible errors.
Recent Submissions

Degradation in ConePlate Rheometry
(201807)We analyze quantitatively the oxidative degradation of a sample in a coneplate rheometer, as oxygen diffuses inward, radially, from the free boundary. We examine rheometer error mitigation by means of nitrogen blanketing, ... 
Exact Solutions for Oscillatory Shear Sweep Behaviors of Complex Fluids from the Oldroyd 8constant Framework
(201705)Largeamplitude oscillatory shear flow (LAOS) is a popular for studying the nonlinear physics of complex fluids. Specifically, the strain rate sweep (also called the strain sweep) is used routinely to identify the onset ... 
Exactsolution for Coneplate Viscometry
(201708)The viscosity of a Newtonian fluid is often measured by confining the fluid to the gap between a rotating cone that is perpendicular to a fixed disk. We call this experiment coneplate viscometry. When the cone angle ... 
Fluid Elasticity in Plastic Pipe Extrusion: Loads on Die Barrel
(201707)In large thick plastic pipe extrusion, the residence in the cooling chamber is long, and the melt inside the pipe sags under its own weight, causing the product to thicken on the bottom (and to thin on the top). To compensate ... 
Elastomers in LargeAmplitude Oscillatory Uniaxial Extension Revisited
(201707)In this work, we subject elastomers to a fixed prestretch in uniaxial extension, ε p , upon which a largeamplitude, ε 0 , oscillatory uniaxial extensional (LAOE) deformation is superposed. We find that if both ε p and ε ... 
Elastomers in Oscillatory Uniaxial Extension
(201602)In this work, we subject elastomers to a fixed prestretch in uniaxial extension, ε p , upon which a largeamplitude, ε 0 , oscillatory uniaxial extensional (LAOE) deformation is superposed. We find that if both ε p and ε ... 
Normal Stress Differences from Oldroyd 8Constant Framework: Exact Analytical Solution for LargeAmplitude Oscillatory Shear Flow
(201703)The Oldroyd 8constant framework for continuum constitutive theory contains a rich diversity of popular special cases for polymeric liquids. In this paper, we use part of our exact solution for shear stress to arrive at ... 
Exact Analytical Solution for LargeAmplitude Oscillatory Shear Flow from Oldroyd 8Constant Framework: Shear Stress
(201701)The Oldroyd 8constant model is a continuum framework containing, as special cases, many important constitutive equations for elastic liquids. When polymeric liquids undergo largeamplitude oscillatory shear flow, the shear ... 
Polymer Processing Partitioning Approach: Extruding Plastic Pipe
(201601)The proposed thesis research aims at deepening our understanding of the flow of polymer melts through eccentric plastic pipe extrusion dies. Specifically, the proposed thesis research will explore how viscoelasticity affects ... 
Knuckle Formation From Melt Elasticity in Plastic Pipe Extrusion
(201607)When plastic pipe is solidified, it proceeds through a long cooling chamber. Inside the chamber, inside the extrudate, the plastic is molten, and this inner surface solidifies last. Sag then happens inside this cooling ... 
Complex Polymer Orientation
(201507)Previously, we explored the dynamics of a dilute suspension of rigid dumbbells as a model for polymeric liquids in largeamplitude oscillatory shear (LAOS) flow. We derived the expression for the polymer orientation ... 
Plastic Pipe Solidification: Exact Solutions in Cylindrical Coordinates
(201512)For polymer melt solidification in plastic pipe extrusion, we perform an energy balance on the pipe extrudate in cylindrical coordinates to arrive at exact solutions for the temperature, and for the solidification rate. ... 
Transport Phenomena in Eccentric Cylindrical Coordinates
(201609)Studies in transport phenomena have been limited to a select few coordinate systems. Specifically, Cartesian, cylindrical, spherical, Dijksman toroidal, and bipolar cylindrical coordinates have been the primary focus of ... 
Macromolecular Origins of Fifth ShearStress Harmonic in LargeAmplitude Oscillatory Shear Flow
(201608)This study examines the simplest relevant molecular model of a polymeric liquid in largeamplitude oscillatory shear (LAOS) flow: the suspension of rigid dumbbells in a Newtonian solvent. For such suspensions, the viscoelastic ... 
Molecular Origins of Higher Harmonics in LargeAmplitude Oscillatory Shear Flow: Shear Stress Response
(20161101)Recent work has focused on deepening our understanding of the molecular origins of the higher harmonics that arise in the shear stress response of polymeric liquids in largeamplitude oscillatory shear flow. For instance, ... 
Bubble Growth From First Principles
(20160705)We consider the simplest relevant problem in the foaming of molten plastics, the growth of a single bubble in a sea of highly viscous Newtonian fluid, and without interference from other bubbles. This simplest problem has ... 
Polymer Fluid Dynamics: Continuum and Molecular Approaches
(20160620)To solve problems in polymer fluid dynamics, one needs the equation of continuity, motion, and energy. The last two equations contain the stress tensor and the heatflux vector for the material. There are two ways to ... 
Temperature Rise in a Verging Annular Die
(20151207)Plastic pipes, tubes or catheters are extruded by pressure‑driven flows through annular dies. Whereas die lands are straight, the section connecting the die land to the extruder either converges or diverges, converging ... 
Reflections on Inflections
(20151111)In plastics processing, the single most important rheological property is the steady shear viscosity curve: the logarithm of the steady shear viscosity versus the logarithm of the shear rate. This curve governs the volumetric ... 
Chain Extended Poly(3—hydroxybutyrate) With Improved Rheological Properties and Thermal Stability, Through Reactive Modification in the Melt State
(20151004)Branching and crosslinking of polyhydroxybutyrate (PHB) is accomplished for the first time through reactive modification in the melt state, using dicumyl peroxide (DCP) as the freeradical initiator and a trifunctional ...