Embedded Files
lwalker [at] andrew.cmu.edu
Doherty Hall 3120
412.268.3020
Scroll down for list of openings in the group!
Scroll down for list of openings in the group!
Current PhD students
Olivia Haider
Jeremy Kach (co-advised A. Khair)
Michal Roguski
Sunny Surprenant (co-advised D. Chan)
Maryam Ali (co-advised R. Tilton)
Current Postdoctoral Researchers
Dr. Jung Hung Ahn
Current MS students
PhD Alumni
Brian Priore, “Morphology Development of Immiscible Polymer Blends in Complex Flow Fields” (Ph.D. May 2001)
My Hang Truong, “Controlling Cylindrical Micellar Rheology through Intelligent Formulation” (Ph.D. May 2002)
Yenny Christanti, “The Effect of Viscoelasticity on the Jet Break-Up and Atomization of Polymer Solutions” (Ph.D. May 2002)
Michael J. Gerber, “The Characterization of Polymerized Worm-like Surfactant Micelles” (Ph.D. May 2006)
Lilo D. Pozzo, “Templating Nanoparticles Using Thermo-Reversible Soft Crystals” (Ph.D. May 2006)
Gitanjali K. Seevaratnam, “Dynamic Wetting of Non-Newtonian Fluids” (Ph.D. May 2006) – co-advised with Steve Garoff (Physics)
Eric D. Miller, “InkJet Printing of Solid-Phase Growth Factor Patterns to Direct Cell Fate” (Ph.D. Dec. 2007, Biomedical Engineering) 2003-2004 Dowd-ICES Fellow - co-advised with L. Weiss (Robotics) and P. Campbell (BME)
Daniel M. Kuntz, “Dilute and Concentrated Phase Behavior of Water-Soluble Rodlike Polyelectrolyte-Surfactant Aggregates” (Ph.D. May 2008)
Yuli Wei, “Dynamic Wetting of Viscous and Viscoelastic Fluids” (Ph.D. August 2009, Physics) – co-advised with S. Garoff (Physics)
Wingki Lee, “Microscale Thread Formation as a Mechanism to Generate Submicron Droplets” (Ph.D. May 2010) – co-advised with S. L Anna
Theresa A. LaFollette, “Block Copolymer Robustness and Stability of Templated Protein Nanocomposites,” (Ph.D. August 2010), NSF Fellow
Viet Lam, “Structure of rod-like polyelectrolyte-surfactant aggregates in solution and adsorbed layers,’’ (Ph.D. May 2011)
Nicholas Alvarez, “An Experimental and Theoretical Study of Surfactant Dynamics at Microscale Interfaces,” (Ph.D. May 2011), NSF Fellow – co-advised with S. L. Anna
Matthew Reichert, “Using Microscale Interfaces to Connect Transport Dynamics, Interfacial Mechanics, and Coalescence Behavior for a Model Oil-Dispersant-Aqueous System,” (Ph.D. May 2013)
Vicki Cheng, “Structure, Mechanics, and Transport in Block Copolymer-Nanoparticle Composites at the Macroscopic and Nanometric Lengthscales,” (Ph.D. Aug 2013), Bayer Fellow
Todd M. Moyle, “Surfactant Mediated Tipstreaming as a Tool for Designed Production of Sub-Micron Sized Droplets,” (Ph.D. May 2015), – co-advised with S. L. Anna
Javier A. Lanauze, “Transient Electrohydrodynamics of Low-Conductivity Drops,” (Ph.D. May 2016) – co-advised with A. S. Khair
Melissa M. Dao, “Impact of Dispersed Nanoparticles in Block Copolymer Soft Solids,” (Ph.D. May 2016) – co-advised with M. M. Domach
Stephanie M. Kirby, “Controlled Generation and Characterization of Multicomponent Fluid/Fluid Interfaces,” (Ph.D. May 2017) – co-advised with S. L. Anna
Blake J. Bleier, "Droplet-Based Approaches to Probe Complex Behavior in Colloidal Fluids with High Composition Resolution" (Ph.D. May 2018) - co-advised with S. L. Anna
Raj Sengupta, "Electrohydrodynamics of surfactant-laden Fluid-fluid interfaces," (Ph.D. May 2019) - co-advised with A. S. Khair
Michael L. Davidson, "Controlling Adsorption of Surfactants, Polymers and Particles to Fluid/Fluid Interfaces with Interfacial Processing" (Ph.D. May 2020)
Junchi Ma, "Impact of Interfacial Properties, Colloidal Interactions and Colloidal Structures on Coalescence of Oil/Water Interfaces" (Ph.D. June 2021)
Connor Valentine “Self-Assembled structures with crystalline order in aqueous block polymer systems: Understanding nanoscale structure and material processing to achieve desirable properties” (Ph.D. March 2022)
Deyu (Lydia) Yang “High compositional resolution characterization of multi-component macromolecular systems” (Ph.D. April 2022)
MS Alumni (MS Project)
Nisha Holla (M.S. 2013) “Characterization of Transport Processes in a Microtensiometer Device” - co-advised w/ S. L. Anna
Prashansa Desai (M.S. 2014) “Microfluidic Study of Crystallization and Phase Transitions of Concentrating Droplets” – co-advised w/ S.L.Anna
Lisa D’Costa (M.S. 2015) “Interfacial Adsorption of Surfactant-Particle Complexes,” – co-advised w/ S.L.Anna
Akshara Shetty (M.S. 2016) “Rheology of Cellulose Solutions”
Yitian Chen (M.S. 2017) - co-advised w/ J.W. Schneider
Yan Wu (M.S. 2017) - co-advised w/ J.W. Schneider
Jiachun Shi (M.S. 2018) - co-advised w/ A. S. Khair
Hanqin Zhao (M.S. 2018) - co-advised w/ J.W.Schneider
Yiqun Fu (M.S. 2018) - co-advised w/ J.W.Schneider
Qiuyang (Emma) He (M.S. 2019) - co-advised w/ J.W.Schneider
Gautham Swaminathan (M.S. 2019) - co-advised w/ J. R. Kitchin
Siddhant Meenor (M.S. 2019) - co-advised w/ J. R. Kitchin
Qianxia Zhang (M.S. 2020)
Xiyu Qin (M.S. 2020)
Miras Bakhrayev (M.S. 2020)
Soumyajit Chowdhuri (M.S. 2020)
Minji Chan (M.S. 2021)
Sanjana Polavarapu (M.S. 2022)
Sejal Vispute (M.S. 2022) - co-advised w/ R.D. Tilton
Shipica Uddigiri (M.S. CPS 2022) - co-advised w/ R.D. Tilton
Yijie Chen (M.S. 2022)
Openings in the group
Openings in the group
We are always looking for talented, enthusiastic and driven researchers to join the group. Current openings include:
MS projects
Design of multicomponent high through-put experiments for formulation, Collaboration with Robert Tilton (ChE) and input from Proctor & Gamble: Formulation of personal care products (among others) requires characterization of multicomponent mixtures. As the number of components increases, the parameter space grows rapidly and requires adaptation of well defined and existing analytical methods. As high-throughput experimentation (HTe) and fully automated laboratories are being developed, the implementation of analytical tools needs re-visiting as well as the tools to collect, organize, trouble shoot, and interpret data. In this work, two examples from an industrial collaborator at P&G will be used. Both examples represent systems that were characterized using an automated laboratory; one was effective and the other led to artifacts that hindered the use of automated approaches. Development of techniques to characterize, first, the critical micelle concentration (cmc) in mixtures of surfactants using either dye solubilization or dynamic light scattering (DLS), and second, the sedimentation rate in coacervate mixtures of oppositely charged polymers and surfactants using light scattering (DLS and SLS) will be performed. Time-dependent phenomena will be fully characterized to determine how these will impact high-throughput and automated experimentation. Results will be used to propose and potentially improve HTe and automated laboratory experiments. Skills gained in project: Experimental/Computational. Solution preparation and characterization, light scattering, and basic colloidal characterization. Data visualization and organization tools will be utilized.
Modeling of properties of polymer melts for polymer upcycling process design, Part of a collaboration with researchers at UCSB: A proposed approach to reduction in the amount of polyolefin waste is to “upcycle” the material back to a useable feedstock. This involves de-polymerization of commercial materials using several different approaches. In this work, the goal is to utilize existing polymer processing units to couple catalytic de-polymerization with mechanical chain scission to optimize the impact. In this project, we will use a software package, REPTATE, to predict the flow properties of different samples of polymers. The approach will be to start with a ideal molecular weight distribution (MWD) and branching level, then apply different depolymerization schemes (stochastic, targeted, random, etc), recalculate the MWD. For each stage of the reaction process, the flow behavior, or rheology, will be predicted and used as a tool to inform and design experimental studies. Skills gained in project: Computational. Numerical simulation of constitutive equations, development of Monte Carlo methods, combination of software packages, analysis of rheological features.
Undergraduate researchers to work as part of the Build Team or on individual projects - positions open for AY22-23
Quantify impact of excipients on liquid-liquid phase separation: PEG precipitation has been shown as an effective approach to determine phase separation in multicomponent mixtures, which varies with formulation conditions (such as pH, ionic strength, additives, etc.). The goal of this project is to systematically quantify the effects of pH and various excipients on the phase separation macroscopically, which will further be compared with microfluidic results. The project will involve tools for the separation and concentration measurement of multicomponent solutions. Fundamental fabrication and use of a droplet-based microfluidic device will be partially involved.
Please contact Prof. Lynn Walker for questions and descriptions.
Report abuse