Horst Henning Winter | |
---|---|
Born | Stuttgart, Germany | September 9, 1941
Relatives | Ernst R. G. Eckert (father-in-law) |
Awards | Bingham Medal |
Academic background | |
Education | Dipl-Ing., Polymer Engineering M.S., Chemical Engineering Ph.D., Polymer Rheology |
Alma mater | University of Stuttgart Stanford University |
Academic work | |
Institutions | University of Massachusetts Amherst |
Horst Henning Winter is a German American chemical engineer,educator and researcher. He is a distinguished professor at the University of Massachusetts Amherst, [1] and was the executive editor of Rheologica Acta from 1989 to 2016,where he has served as honorary editor since 2017. [2]
Winter's research focuses on the measurement and modelling of soft matter rheology. He has given special attention to gelation,glass transition and flow-induced structure in polymers. Winter and his group developed highly-specific experimental methods,as well as analysis tools and visualization methods to support this research. [3]
In 1996,Winter was awarded the Bingham Medal in recognition of his contributions to experimental rheology,as well as rheometry of gels and polymer melts. [4] He was also chosen for the National Science Foundation Creativity Award in 1997 and the Alexander von Humboldt Senior Scientist Award in 1999,during which he was a visiting professor at the Max Planck Institute of Colloids and Interfaces in Potsdam. [5] Winter is furthermore the co-founder of IRIS Development and founder of 2D Matter. [6] Winter lives with his wife Karin. They have four children.
Winter was born in Stuttgart,Germany in 1941. He obtained a Dipl-Ing. in Mechanical Engineering at the University of Stuttgart in 1967. He then received an M.S. from Stanford University in Chemical Engineering in 1968. He returned to University of Stuttgart where he completed his Ph.D. in 1973 in Polymer Rheology, [1] an interest he continued pursuing immediately after graduation through work as a DFG (German Research Foundation) fellow at the Rheology Research Center at the University of Wisconsin-Madison. In 1976,this led to a habilitation thesis on viscous dissipation in polymer flow.
Winter began his teaching career as Privatdozent for Rheology at University of Stuttgart in 1976. He transferred as associate professor to the University of Massachusetts Amherst in 1979,becoming full professor in 1984,and was named distinguished professor in 1994. At the same time,he also became the director of the Laboratory for Experimental Rheology. [7]
He was the executive editor of Rheologica Acta from 1989 to 2016,served on the editorial board of Journal of Rheology from 1989 to 2005,and of Journal of Non-Newton Fluid Mechanics from 1989 to 2018. From 2009 to 2012,he served as director of the Fluid Dynamics Program at the National Science Foundation (NSF),after which he returned to UMass. [8]
In 2007,Winter founded IRIS Development LLC,a software service company in support of experimental rheology and rheology education. The company holds the 'Amherst Rheology Courses' [9] and licenses IRIS RheoHub, [10] a software tool used for research and teaching by academic researchers,and by industrial decision makers so that they can utilize rheology efficiently. A main feature of the software is the visualization of rheology results by a direct overlay of experimental data and predictions from rheology theory. [6]
Winter founded 2D Matter LLC in 2018. It promotes the engineering of two-dimensional materials such as clay,graphene,zeolite,as generated by the exfoliation of precursors with layered structure.
In a series of papers,Winter and his co-worker Fancois Chambon characterized the time-evolving rheology of polymers during gelation. They discovered that the gel point is marked by power-law relaxation over a wide range of frequencies/time-scales. Depending on the type of gel,the scaling exponent may adopt a value between -1 and 0. This behavior makes it easy to uniquely identify the gel point during both chemical and physical gelation processes. [11] The experimental findings initiated active development of theories for the rheology of gels in the physics community. The findings also had technological impact,supporting the commercial development of gels as adhesives,sealants,toners,and biological materials. The original paper continues to be the most cited publication ever in the Journal of Rheology. [12]
Winter and his co-worker Michael Baumgärtel wrote the parsimonious model,the first robust code to convert dynamic mechanical data into their relaxation time spectrum [13] and,together with Alois Schausberger,they showed that linear,flexible polymers of uniform chain length relax in a self-similar relaxation time spectrum now known as the BSW spectrum. The BSW relation provides a convenient starting condition for exploring polymer systems of more diverse molecular architecture. For generating biaxial extension in small samples,Winter invented the technique of lubricated squeeze flow and studied it jointly with Christopher Macosko. This simple technique was the first one to provide reliable step-strain biaxial extension data which is important for accurate modeling of polymer processing operations such as film blowing and blow molding. [14]
Winter,along with Miriam Siebenbürger and Matthias Ballauff,discovered rheological scaling laws that govern the glass transition. [15] This discovery led to the development of a new criterion for distinguishing gels from soft glass. [16] With Alessio Zaccone,they also developed rheological scaling laws for colloidal gels,which take into account the power-law growth kinetics in the colloidal self-assembly. [17]
Winter also contributed to the numerical modeling of polymer processing operations and his 1977 paper on viscous dissipation in flowing polymer systems is widely considered a classic in the area. [18]
Winter and his group have also worked on the efficient decomposition of solid particles into thin leaves. They have produced organo-clay sheets from clay,graphene from graphite,and 2-D zeolites from zeolite monolith particles. [19] Their novel process for graphite-to-graphene exfoliation has produced pristine graphene at substantially increased yield. [7]
Rheology is the study of the flow of matter,primarily in a fluid state,but also as "soft solids" or solids under conditions in which they respond with plastic flow rather than deforming elastically in response to an applied force. Rheology is a branch of physics,and it is the science that deals with the deformation and flow of materials,both solids and liquids.
A gel is a semi-solid that can have properties ranging from soft and weak to hard and tough. Gels are defined as a substantially dilute cross-linked system,which exhibits no flow when in the steady-state,although the liquid phase may still diffuse through this system. A gel has been defined phenomenologically as a soft,solid or solid-like material consisting of two or more components,one of which is a liquid,present in substantial quantity.
The Deborah number (De) is a dimensionless number,often used in rheology to characterize the fluidity of materials under specific flow conditions. It quantifies the observation that given enough time even a solid-like material might flow,or a fluid-like material can act solid when it is deformed rapidly enough. Materials that have low relaxation times flow easily and as such show relatively rapid stress decay.
Bubble gum is a type of chewing gum,designed to be inflated out of the mouth as a bubble.
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In materials science and continuum mechanics,viscoelasticity is the property of materials that exhibit both viscous and elastic characteristics when undergoing deformation. Viscous materials,like water,resist shear flow and strain linearly with time when a stress is applied. Elastic materials strain when stretched and immediately return to their original state once the stress is removed.
A rheometer is a laboratory device used to measure the way in which a viscous fluid flows in response to applied forces. It is used for those fluids which cannot be defined by a single value of viscosity and therefore require more parameters to be set and measured than is the case for a viscometer. It measures the rheology of the fluid.
Manfred Hermann Wagner is the author of Wagner model and the molecular stress function theory for polymer rheology. He is a Professor for Polymer engineering and Polymer physics at the Technical University of Berlin.
Wagner model is a rheological model developed for the prediction of the viscoelastic properties of polymers. It might be considered as a simplified practical form of the Bernstein-Kearsley-Zapas model. The model was developed by German rheologist Manfred Wagner.
Curing is a chemical process employed in polymer chemistry and process engineering that produces the toughening or hardening of a polymer material by cross-linking of polymer chains. Even if it is strongly associated with the production of thermosetting polymers,the term "curing" can be used for all the processes where a solid product is obtained from a liquid solution,such as with PVC plastisols.
Markus Reiner was an Israeli scientist and a major figure in rheology.
Materials that are used for biomedical or clinical applications are known as biomaterials. The following article deals with fifth generation biomaterials that are used for bone structure replacement. For any material to be classified for biomedical applications,three requirements must be met. The first requirement is that the material must be biocompatible;it means that the organism should not treat it as a foreign object. Secondly,the material should be biodegradable;the material should harmlessly degrade or dissolve in the body of the organism to allow it to resume natural functioning. Thirdly,the material should be mechanically sound;for the replacement of load-bearing structures,the material should possess equivalent or greater mechanical stability to ensure high reliability of the graft.
Ashish Kishore Lele is an Indian chemical engineer,rheologist and the Director of the National Chemical Laboratory,Pune. He is known for his researches on micro and mesostructure of polymers and is an elected fellow of the Indian Academy of Sciences,and the Indian National Academy of Engineering. The Council of Scientific and Industrial Research,the apex agency of the Government of India for scientific research,awarded him the Shanti Swarup Bhatnagar Prize for Science and Technology,one of the highest Indian science awards for his contributions to Engineering Sciences in 2006. He received the Infosys Prize in 2012.
Yogesh Moreshwar Joshi is an Indian chemical engineer,rheologist and the Pandit Girish &Sushma Rani Pathak Chair Professor at the Indian Institute of Technology,Kanpur. He is known for his studies on metastable soft matter and is an elected fellow of the Society of Rheology,Indian National Science Academy,Indian Academy of Sciences,and Indian National Academy of Engineering. In 2015,the Council of Scientific and Industrial Research,the apex agency of the Government of India for scientific research,awarded Joshi the Shanti Swarup Bhatnagar Prize for Science and Technology for his contributions to Engineering Sciences.
Christopher Ward Macosko (1944) is an American chemical engineer and professor emeritus in the department of chemical engineering and materials science at the University of Minnesota. He is internationally known for his work in polymer science and engineering,especially in the areas of rheology and polymer processing. Macosko is an author of more than 500 academic papers,dozens of patents,and two books including the text:"Rheology:Principles,Measurements and Applications". He served as director of the Industrial Partnership for Research in Interfacial and Materials Engineering (IPRIME),a university-industry consortium at the University of Minnesota,from 1999 to 2018. Macosko and his wife Kathleen have been married since 1967 and are long-time residents of Minneapolis. They have four children and 12 grandchildren.
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Gareth Huw McKinley is Professor of Teaching Innovation in the Department of Mechanical Engineering at Massachusetts Institute of Technology (MIT).
Interfacial rheology is a branch of rheology that studies the flow of matter at the interface between a gas and a liquid or at the interface between two immiscible liquids. The measurement is done while having surfactants,nanoparticles or other surface active compounds present at the interface. Unlike in bulk rheology,the deformation of the bulk phase is not of interest in interfacial rheology and its effect is aimed to be minimized. Instead,the flow of the surface active compounds is of interest.
Ronald G. Larson is George G. Brown Professor of Chemical Engineering and Alfred H. White Distinguished University Professor at the University of Michigan,where he holds joint appointments in macromolecular science and engineering,biomedical engineering,and mechanical engineering. He is internationally recognized for his research contributions to the fields of polymer physics and complex fluid rheology,especially in the development of theory and computational simulations. Notably,Larson and collaborators discovered new types of viscoelastic instabilities for polymer molecules and developed predictive theories for their flow behavior. He has written numerous scientific papers and two books on these subjects,including a 1998 textbook,“The Structure and Rheology of Complex Fluids”.
Rachel (Raya) Takserman-Krozer [] was a theoretical physicist and professor of rheology. Takserman-Krozer worked on diverse aspects of theoretical physics ranging from theory of relativity to studies of polymers and their flow. Her scientific work includes contributions to behaviour of polymers and polymers solutions in velocity fields,theory of spinnability,problems of phenomenological rheology,and molecular-statistical theory of polymer networks. Takserman-Krozer worked across several countries including Russia,Poland,Israel,and Germany.