Laboratory Learning Program 2022 - Measuring the Molecular Weights and Molecular Sizes of Short-Chain Polymers by Multidetector Gel Permeation Chromatography (CBE-02)

Research Opportunity Number: CBE-02

Project Title:  Measuring the Molecular Weights and Molecular Sizes of Short-Chain Polymers by Multidetector Gel Permeation Chromatography

Project Summary: A polymer's molecular weight is one of its most basic characteristics, and its size in solution determines its ability to viscosify ("thicken") fluids ranging from shampoo to motor oil to turkey gravy. While multidetector gel permeation chromatography (GPC) is a very powerful technique for characterizing molecular weight and size, it encounters challenges for shorter-chain polymers (molecular weight from about 500-20000 g/mol), where some of the approaches used for higher-molecular-weight polymers break down. The student will use a four-detector GPC system (UV/vis, refractive index, light scattering, viscosity) to characterize molecular weight and size. Measurements will be made on series of narrow-distribution polystyrenes, as well as poly(ethylene oxides) and other polymers we may identify, to test correlations such as the so-called “universal calibration curve” which are commonly used at higher molecular weights to enable a lab to calibrate a GPC with one type of polymer, and measure another. The student may also measure polymer solution refractive indices as needed, as this is essential data for determining molecular weight from light scattering.

Student Roles and Responsibilities: Student will prepare the solutions, conduct the GPC and refractometry measurements, and analyze the results.

Additional Considerations:  Start and end dates are flexible, but the student should be available essentially full-time (at least 35 hours/week) for a minimum of 7 weeks.

Department/Institute:  Chemical and Biological Engineering

Faculty Sponsor:   Richard A. Register

Participation Dates: June 27 - September 2, 2022

Stipend Offered:  $0

Number of Internships Available: 0-1

Application Deadline: March 15, 2022, midnight eastern daylight time