Srinivasa R. Raghavan

University of Maryland

Chemical Engineer

Fellow, Elected 2023

Srinivasa (Srini) Raghavan has been a ‘rheologist’ for the past 30 years. He was introduced to rheology during his Ph.D. at NCSU in 1992-98 with Prof. Saad Khan. In his Ph.D., he made key contributions to the rheology of colloidal dispersions. Thereafter, in his postdoc at Delaware with Prof. Eric Kaler, he explored the rheology of wormlike micelles (WLMs). Srini’s Ph.D. and postdoc work have proved influential and 10 of his papers have garnered 180+ citations.

Srini began his independent academic career at the Univ. of Maryland (UMD) in 2001 and has been there for the past 22 years, during which time he has advised 36 Ph.D. students. He has published 180+ papers, which have been cited > 16,000 times, with an h-index of 73. Rheology has been a central theme in his research ⎯ more than 100 of his UMD papers have had a rheology focus, and 30 of these papers have already reached 100+ citations.

Srini is recognized as a leader in studying the rheology of self-assembled systems, especially those containing WLMs, vesicles, and amphiphilic polymers. He has published seminal studies on WLMs in water, in nonpolar oils, and in polar organic liquids like glycerol. He has also pioneered the creation of ‘smart fluids’ with tunable rheology, where the rheology can be switched by external stimuli such as temperature and light. In particular, light-responsive or photorheological (PR) fluids have been a key innovation from Srini’s lab. His first paper on PR fluids in JACS popularized this topic and his subsequent papers reported a variety of PR fluids based on WLMs, colloidal particles, and polymers. All these fluids were made using simple, widely available components, rather than by resorting to complex chemistry. The culmination of this work was the report of a PR fluid based on WLMs whose viscosity could be reversibly switched a million-fold by shining UV and visible light.

The most meaningful contribution from Srini’s lab was their discovery that a biopolymer modified with hydrophobic groups could convert liquid blood into a gel. Gelation arose because the polymer bridged blood cells into a network. The same polymer could stop bleeding from lethal injuries in animals. A startup company (Medcura) was established by Srini’s students to commercialize this technology. In 2021, a consumer product made by Medcura called “Rapid-Seal Wound Gel” became available at US pharmacies. As the name indicates, this gel rapidly stops bleeding from wounds.

Srini has been a member of SoR since 1994 and in fact his first presentation at any conference was at SoR (and his first paper in 􀀭oR). He has been the Technical Co-Chair of one SoR meeting (Madison, 2009) and the Local Arrangements Co-Chair for another (Baltimore, 2015). He co-taught a short course on ‘Surfactant Rheology’ at the ICR in Monterey in 2008. He has given invited talks at SoR and ICR meetings and has contributed more than 30 talks at these meetings over the years.