Hsu Research Group – People
Deepa Puthanparambil
I joined Prof. Hsu’s group in April 2008 as a Postdoctoral Research Associate. My area of research is in the formation of flexible polyurethane foams from soy based polyols and their morphological evolution characterized through spectroscopy. The most crucial aspect
of my research deals with the miscibility of water in the reactive mixtures. High field NMR and FTIR are employed to determine the miscibility behavior of the polyols in D2O at the molecular level. The phase separation during foam formation resulting in the final morphology was characterized by utilizing FTIR spectroscopy.
I obtained my PhD in Chemistry from National Institute for Interdisciplinary Science and Technology, Trivandrum, Kerala, India, where I worked on a novel melt route for the synthesis of cycloaliphatic polyurethanes and the self organization of the synthesized polymers.
Huimin Bao
I joined Prof. Hsu’s group in the end of February, 2009. My research work in Umass is mainly related with the crystallization behavior of random copolymer with low molecular weight crystalline oligomers, the latter ones havesimilar crystalline segments as the random copolymer. Study on this system can be helpful to understand more about the fundamental process in random copolymer crystallization. What’s mo
re, this work has great importance in adhesive application. Low Field NMR is used in my work, which can differentiate physical environment in random copolymers and give more information both on the interfacial phase and the chain dynamics.
I got my Ph. D in Nanjing University, China. My research work then was related with the phase transition and ferroelectric relaxor behavior in Vinylidene Fluoride based terpolymers.
Jeff Kalish:
Jeff received his undergraduate degree in Materia
ls Science and Engineering at the University of Illinois at Urbana-Champaign in 2006.An undergraduate research project sparked his curiosity and interest in structure and morphology of semi-crystalline polymers. Jeff started at UMass-Amherst in 2006, joined the Hsu group, and investigates the structure, stability, and morphology associated with semi-crystalline poly(lactic acid) and blends of ethylene-based copolymers. One theme throughout both projects is crystallization of polymers with defects, whether stereo-defects or co-mer units that hinder crystallization and overall crystallinity. Defects not only affect crystallization behavior, but also chain dynamics, viscosity, and melt properties.
Suriyakala Ramalingam:
My research is focused on study of structure and molecular properties of semicrystalline fluorinated polymers targeted for stable and controlled drug releasin
g polymer matrix. The drug release from the polymeric matrix is greatly affected by physical and chemical properties of both polymer and drug materials and also by processing conditions. My studies mainly focus on number of factors which control the drug release kinetics such as surface morphology, percolated drug-polymer structure, properties of release medium and release mechanism and so on. All these factors are connected with processing conditions such as storage temperature, solvent used in film casting and evaporation technique on material stability, crystalline structures and surface morphology which all affect drug release kinetics. In addition, I also study kinetics and thermodynamics associated with the phase behavior and miscibility of polymer blends used in hot-melt adhesives formulation.
Casey received his undergraduate degree in Chemistry in 2004 from Amherst
College and joined Professor Hsu’s group in the Polymer Science and Engineering
department in 2005. Most of his work deals with the chemistry of polyurethanes
and their physical properties. His work can be divided into two categories. Reactive
aqueous polymer isocyanate blends involving polymer latexes and dispersible
liquid multifunctional isocyanates. These polyurethane based adhesives are not only
strong and resilient, but due to their method of delivery (i.e. water based),
they are environmentally appropriate due to no VOCs (volatile organic compounds). The
second involves functionalizing polyurethane based catheter surfaces for
preventing coagulation of blood. Both projects involve the physical aspects of
miscibility and secondary forces (specifically hydrogen bonding), and
spectroscopic characterization techniques.
Dr. Howard D. Stidham stid@blackhawk.chem.umass.edu
My research interests are vibrational/spectra and spin resonance spectra: molecular spectra and structure; computation of molecular properties. My current research efforts are divided between spectroscopic and computational studies of small molecules and high polymers. Raman and infrared techniques are used to investigate molecular dimensions, conformations and order changes on phase transition. Cooperativity theory in biological systems is a recent further interest.
