Work in the Cohen group was presented at the 2012 APS March Meeting in Boston, MA.
- Thu. Mar. 1, 2:03 PM - 2:15 PM, Room 157C, Boston Convention Center(Session W44)
Microtextured Omniphobic Surfaces by Solution Spraying of Fluorodecyl POSS/PMMA Blends
Siddarth Srinivasan, Gareth H. McKinley and Robert E. Cohen
- Thu. Mar. 1, 4:06 PM - 4:18 PM, Room 162B, Boston Convention Center(Session X50)
Liquid-impregnated surfaces: overcoming the limitations of superhydrophobic surfaces for robust non-wetting and anti-icing surface
J. David Smith, Rajeev Dhiman , Ernesto Reza-Garduno , Gareth H. McKinley , Robert E. Cohen , Kripa Varanasi
- Tue. Feb. 28, 9:24 AM - 9:36 AM, Room 161, Boston Convention Center(Session H48)
Hydrogen Bonding Based Layer-by-Layer Assembly of Poly(vinyl alcohol) with Weak Polyacids
Hyomin Lee, Remy Mensire , Robert E. Cohen and Michael F. Rubner
Graduate student Siddharth Srinivasan won the Grand Prize at the PPST poster session at the 2012 MIT Polymer Day featuring over 50 posters. The Polymer Day was a half-day event that featured a broad array of polymer research across the MIT polymer community, with representatives from Materials Science and Engineering, Chemical Engineering, Biological Engineering, Mechanical Engineering, and Chemistry.
Work in the Cohen group was presented at the 2011 MRS Fall Meeting in Boston, MA.
- Tue. Nov. 29, 2:00 PM, Room 203 (Hynes) (JJ4.2)
"Polymeric Backpacks for Cell-Mediated Drug Delivery"
Jonathan Gilbert, Aaron Anselmo, Albert Swiston, Nishit Doshi, Samir Mitragotri, Robert Cohen and Michael Rubner
- Mon. Nov. 28, 8:00 PM, Hynes Exhibition Hall D (MM3.15-Poster Session)
"Immune Cell Multi-Layers Assembled Using Layer-by-Layer Processing"
Girma T. Endale, Michael F. Rubner and Robert E. Cohen;
Prof. Cohen will present a series of two invited lectures as part of the 2011 Bayer Lectureship at the University of Akron, Department of Polymer Engineering.
- Exploitation of Layer-by-Layer Assembly in Bio-Inspired Materials Engineering
Thu. Sept. 22, 2:00 PM, Aggarwal Lecture Hall (Room 130)
- Designing Robust Omniphobic Surfaces
Fri. Sept. 23, 2:00 PM, Aggarwal Lecture Hall (Room 130)
Work in the Cohen group involving Hydrogen-bonded assembly of layer-by-layer films will be presented at the 2011 ACS Fall Meeting in Denver, CO. Group member Hyomin Lee, who is co-advised by Prof. Michael F. Rubner of the Materials Science Department, will present a poster of his work on "Hydrogen-bonded layer-by-layer films composed of poly(vinyl alcohol) and poly(acrylic acid)" in the Polyelectrolyte Complexes and Multilayers Poster Session (Monday, August 29 at 6:00 PM).
The Cohen group would like to bid farewell to our recent graduates: Dr. Jonathan DeRocher, Dr. Wui Siew Tan and Dr. Khek-Khiang (Gary) Chia, and wish them well in their current endeavors.
The Cohen group is pleased to welcome Rémy Mensire, a visiting scholar from Ecole Polytechnique in Paris. Rémy is undertaking a four month internship to satisfy the requirements of the French equivalent of a S.M. degree. During his stay at MIT, he will be working on superwetting textured surfaces fabricated using spray deposition of polymers.
The 18th Princeton-MIT Microsymposium on Polymers featuring the research groups of Profs. Robert Cohen and Richard Register will be held this year in Cambridge on June 1 and 2. The list of presenters can be found here.
Work in the Cohen group on tuning the wettability of mesh surfaces to facilitate fog collection was recently highlighted by MIT News and by CNN. PhDCEP student and 2010-2011 Legatum Fellow Shreerang Chhatre (jointly supervised with Gareth McKinley, Mechanical Engineering) has been working on this project both to gain a detailed and fundamental understanding of wettability and also to further the Legatum Center's mission to spur the deployment of innovative technologies in developing countries. The permeability of the mesh allows fog droplets to impact the collector's surface without completely disrupting the airflow which would drastically limit the flux of water to the surface. Experience with the wettability of surfaces allows one to make a judicious choice of surface coating such that water droplests are attracted to the mesh surface, but also roll off relatively easily, resulting in high collection efficiency.
Professor Cohen presented an invited lecture at the ACS Polymer Division Workshop "Silicon-Containing Polymers and Composites" that was held in San Diego, California on December 12 - 14, 2010. The title of his lecture was "The Role of Fluorodecyl POSS in the Design of Omniphobic Surfaces." In February a similar invited lecture will be presented at the "Smart Coatings Conference" (See www.smartcoatings.org) in Orlando, Florida.
Work in the Cohen group involving ice-phobic and mechanomutable surfaces will be presented at the 2010 MRS Fall Meeting in Boston, MA.
- Tue. Nov. 30, 6:45 PM, Sheraton Republic B (II6.4)
"Water Wettability and Ice Adhesion of Fluorodecyl POSS-containing Polymer Nanocomposites"
Adam J. Meuler, J. David Smith, Kripa K. Varaniasi, Joseph M. Mabry, Gareth H. McKinley, Robert E. Cohen
- Thu. Dec. 2, 8:00 PM, Hynes Exhibition Hall D (P10.16)
Lin Han, Lifeng Wang, Khek-Khiang (Gary) Chia, Robert E. Cohen, Michael F. Rubner, Mary C. Boyce, Christine Ortiz
Cohen group member Adam Meuler will be giving a number of presentations at the 2010 AIChE Annual Meeting in Salt Lake City, UT.
- Sun. Nov. 7, 2:00 PM, Hall 1 (4ab)
"Fabrication and Evaluation of Omniphobic Surfaces for Liquid Repellency and Reduced Ice Adhesion"
Adam J. Meuler
- Wed. Nov. 10, 8:50 AM, Topaz Room (429b)
"Relationships Between Water Wettability and Ice Adhesion"
Adam J. Meuler, J. David Smith, Kripa K. Varanasi, Joseph M. Mabry, Gareth H. McKinley, Robert E. Cohen
- Fri. Nov. 12, 9:20 AM, 252 A/B (744c)
"Towards Robust Hydrophobic and Oleophobic Surfaces"
Adam J. Meuler, Kyoo-Chul (Kenneth) Park, Joseph M. Mabry, Gareth H. McKinley, Robert E. Cohen
A number of Cohen group members will be giving talks at the 240th ACS National Meeting in Boston, MA. Below is a list of the presenters:
- Sun. Aug. 22, 10:10 AM, Westin Carlton (COLL 31)
"Girifalco: Good analysis of fluoroalkylated silicon-containing surfaces"
Shreerang S. Chhatre, Jesus O. Guardado, Brian M. Moore, Joseph M. Mabry, Gareth H. McKinley, Robert E. Cohen
- Mon. Aug. 23, 10:20 AM, Westin Grand Ballroom D (POLY 135)
"Injectable cellular 'Backpacks' lead to cell aggregate self-assembly"
Albert J. Swiston, Jonathan Gilbert, Darrell Irvine, Robert Cohen, Michael Rubner
- Mon. Aug. 23, 4:00 PM, Westin Carlton (COLL 152)
"Relationships between water wettability and ice adhesion"
Adam J. Meuler, J. David Smith, Kripa K. Varanasi, Joseph M. Mabry, Gareth H. McKinley, Robert E. Cohen
- Wed. Aug. 25, 4:00 PM, Westin Carlton (COLL 433)
"Fundamental studies of clathrate hydrate adhesion"
J. David Smith, Adam J. Meuler, Yuehua Cui, Robert E. Cohen, Gareth H. McKinley, Kripa K. Varanasi
A number of Cohen group members will be participating in the 7th International Symposium on Contact Angle, Wettability, and Adhesion in Danbury, CT. The presenters are:
- Wed. Jun. 23, 3:50PM
"Girifalco-Good Analysis on Perfluorinated SiOx Surfaces"
Shreerang S. Chhatre, Jesus O. Guardado, Joseph M. Mabry, Gareth H. Mckinley, Robert Cohen
- Thu. Jun. 24, 1:30AM
"Robsutness Analysis of Non-Wetting Surfaces Based on Distorted Liquid-Air Interfaces of Droplets"
Kyoo-Chul Kenneth Park, Shreerang S. Chhatre, Wonjae Choi, Robert E. Cohen, Gareth H. McKinley
- Fri. Jun. 25, 11:20AM
"Towards Practical Omniphobic Coatings"
Adam J. Meuler, Kyoo-Chul Kenneth Park, Joseph M. Mabry, Gareth H. McKinley, Robert E. Cohen
Professor Cohen has been elected to the National Academy of Engineering for research on polymer morphology and surfaces, commercial products and processes, successful entrepreneurship, and novel educational programs.
Election to the National Academy of Engineering is among the highest professional distinctions accorded to an engineer. Academy membership honors those who have made outstanding contributions to "engineering research, practice, or education, including, where appropriate, significant contributions to the engineering literature," and to the "pioneering of new and developing fields of technology, making major advancements in traditional fields of engineering, or developing/implementing innovative approaches to engineering education."
Professor Cohen has been awarded a prestigious Astor Visiting Lectureship at Oxford University. In 2010 he will spend a week in residence and deliver a series of lectures in the Department of Engineering Science on dates yet to be determined. The competition for this Lectureship at Oxford is in all fields, not limited to Engineering and Science. The Astor Lectureship provides funding for visits by distinguished academics from the United States for up to one week. Funding covers travel, accommodation, subsistence and an honorarium. Last year 8 awards were made. The successful departments were The China Centre, Earth Sciences, Experimental Psychology, Geography, Medieval and Modern Languages, Pathology, Philosophy, and Statistics.
Cohen has longstanding connections with Oxford, having been a postdoc in Engineering Science in 1973 and a visiting fellow at Balliol College in 2006. He is currently a member of the advisory board of Zyoxel, Ltd. a new startup company that has been launched by Oxford faculty.
The work of Gary Chia was featured on the cover of 25 Years of Langmuir Special Issue.
Many Cohen group members delivered talks and posters at the 2009 MRS Fall Meeting in Boston. Below is a list of the presenters:
- Monday, 2:30 PM-2:45 PM
C2.4. UV Anti-reflection Coating for Large Plastic Optics. Y. Du; L.E. Luna; W. Tan; G.M. Nogueira; M.F. Rubner; R.E. Cohen
- Monday, 3:30 PM-3:45 PM
TT4.1. "Backpack" Functionalized Living Immune Cells. A.J. Swiston; D. Irvine; R.E. Cohen; M.F. Rubner
- Tuesday, 3:45 PM-4:00 PM
DD4.7. Layer-by-Layer Assembly in Nanofluidic Devices. J.P. DeRocher; P. Mao; J. Kim; J. Han; M.F. Rubner; R.E. Cohen
- Tuesday, 8:00 PM-11:00 PM
DD5.19. Formation of Nanoparticle-Containing Multilayers in Nanochannels via Layer-by-Layer Assembly. J. Kim; J.P. DeRocher; P. Mao; M.F. Rubner; R.E. Cohen; J. Han
- Wednesday, 11:30 AM-11:45 AM
WW4.9. Impact of Fiber Length Scale on the Breakthrough Pressure for Non-wetting Textured Surfaces. S.S. Chhatre; A. Tuteja; W. Choi; J.M. Mabry; G.H. McKinley; R.E. Cohen
- Wednesday, 3:30 PM-3:45 PM
QQ8.5. pH-Responsive, Reversibly Swellable Nanotube Arrays. K. Chia; M.F. Rubner; R.E. Cohen
- Thursday, 8:00 PM-11:00 PM
VV7.32. Layer-by-layer Assembled Polymer Coatings for Anti-fog Applications. N. Nuraje; G. Endale; R.E. Cohen; M.F. Rubner
The 17th annual MIT-Princeton Microsymposium on Polymers was held last year in Princeton on June 10 and 11. As usual students and postdocs from the Cohen group at MIT and the Register group at Princeton presented updates on their research projects. The Cohengroup contributions are listed below:
- Jonathan DeRocher "Polyelectrolyte Multilayers in Confined Geometries"
- Shreerang Chhatre "Design Chart for Liquid Repellency"
- Fernando Vasconcellos "Lymphocyte Adhesive Biopolymer Multilayer Films"
- Yi Du "UV Anti-reflection Coatings for PMMA Lenses"
- Adam Meuler "Network Morphologies in Multiblock Terpolymers"
- Gary Chia "pH-Responsive, Reversibly Swellable Nanotube Arrays"
- Erik Williamson "Functional Modifications of Nanoparticle Assemblies via Capillary Condensation"
- Wui Siew Tan "Triblock Copolymers for Temperature Responsive Multilayers"
- Grinia Nogueira "Nanoparticle Arrays with Near-UV and Visible Reflectivity Bands"
Professor Cohen has been active in presenting invited seminars at various universities in this Spring 2009 semester. In February he travelled to Chemical Engineering Departments at Columbia University and at the University of Florida, in March he presented a lecture to the ACS Polymer Discussion Group at North Carolina State University, and in April he visited his graduate school alma mater, Caltech, for a seminar in Chemical Engineering. Also in April he presented a two-lecture sequence at the University of Pittsburgh, Department of Chemical Engineering, where he was the Bayer Distinguished Lecturer for 2009. The abstracts for the two Bayer lectures are shown below:
Bumpy Beetles, Moth Eyes, Butterfly Wings and Patchy Immune Cells: Exploitation of Layer-by-Layer Assembly in Bio-Inspired Materials Engineering
Collaboration with colleague Professor Michael F. Rubner of the Department of Materials Science and Engineering has led to a focus on novel and useful surface/thin-film phenomena that are observed in nature. We have employed a simple and elegant water-based assembly technique to provide conformal multifunctional coatings on a wide variety of substrates. Proper selection of nanoparticles and macromolecules, along with precise control of processing conditions, has enabled us to develop materials that mimic some fascinating natural phenomena: fog harvesting by desert beetles, broadband antireflection of the moth eye, and the brilliant structural colors found in hummingbird and butterfly wings. In a recent project we have assembled payload-containing 'backpack' structures on living immune cells for possible use in in-vivo imaging, therapies and bottom-up tissue engineering.
Designing Robust Omniphobic Surfaces
Superhydrophobic surfaces that display water contact angles greater than 150° with low contact angle hysteresis are becoming commonplace in the materials community. Microscopic pockets of air trapped beneath the high surface tension (glv = 72mN/m) water droplets lead to a composite solid-liquid-air interface in thermodynamic equilibrium. Previous experimental and theoretical work suggests that it should not be possible to form similar fully-equilibrated composite interfaces with drops of low surface tension liquids such as alcohols or alkanes (e.g. pentane: glv = 16 mN/m). In this lecture I will discuss novel surfaces that possess the required re-entrant topographical texture and surface chemistry to support strongly metastable composite solid-liquid-air interfaces for any liquid. Quantitative design parameters will be introduced to guide the development of these novel omniphobic surfaces. Examples that have been realized to date will be demonstrated: these embodiments include lithographically fabricated microhoodoos in silicon, randomly deposited electrospun fiber mats and dip-coated textiles.
PhDCEP student Zekeriyya Gemici (below, third from left, jointly supervised with Michael Rubner, DMSE) has been named one of the 2008 Graduate Student Gold Medal Awardees at the Materials Research Society (MRS) meeting. To achieve this status, Zek had to apply earlier in the fall and be selected to participate in an oral-presentation final competition that took place on Tuesday December 2 at the Hynes Auditorium, site of the MRS meeting.
Zek joins good company. Another Cohen/Rubner ChemE PhD student, Daeyeon Lee, won this prestigious award in 2006. Daeyeon recently finished a postdoc at Harvard and has moved to Philadelphia where he is now an assistant professor in the Chemical Engineering Department at the University of Pennsylvania.
During the Spring term of 2006, Professor Cohen was on leave at Balliol College, Oxford University. He was hosted by Dr. Paul Buckley in the Department of Engineering Science, the site of Professor Cohen's period of postdoctoral study in 1972-73. The sabbatical leave was sponsored in part by the following program:
MIT-Balliol College Exchange Program: Administered by the office of the Dean of Humanities, Arts, and Social Sciences at MIT, this program began in 1986 following a commitment made by William A. Coolidge to fund an exchange program for faculty at MIT and Balliol College at Oxford. The program provides for extended visits at each university. The financial administrator in the Dean's Office coordinates logistics and financial arrangements. All regular members of the MIT faculty are eligible to participate.
- Priority is given to visiting faculty with the greatest potential for professional interaction with the host's faculty.
- Host institutions should avoid imposing any standard "obligations" (e.g. lecturing) on visiting faculty to allow flexibility in arranging the activities of each visit according to the specific needs of the participants.
- The program covers all travel and housing expenses for exchange participants, including one round-trip airfare for their spouse or partner. Visitors to Balliol may participate in a meal plan at the college.
- Visitors to Balliol are provided with an apartment on campus.