 | Synthesis, Development, and Applications of Sensor Materials |
| Position Available in Composites |
| Moisture Effects on Resin Matrix Composites |
| Upcoming Conferences and Seminars |
| New Faculty Position |
| Instability Studies in Nonlinearly Elastic Composite Materials |
| Composite Theory Seminar Series |
| DOE Provides Solicitation for Small Business Research |
| Improving the Purity of Recycled Resin from Pop Bottles |
An internal symposium sponsored by the University Materials Advisory Committee
The University Materials Advisory Committee (UMAC) would like to invite all interested faculty, staff, undergraduate and graduate students to participate in the first internal symposium on Synthesis, Development and Applications of Sensor Materials to be held in room 136 Chemistry on Saturday, January 30, 1993. The prupose of this symposium is to encourage communication between groups interested in sensor materials and applications, coalesce strengths of campus groups working inareas related to sensors, and define new directions for MSU collaborations in this area. It is anticipated that such collaborative efforts will eventually lead to apportunities for future funding in sensor materials research. In conjunction with the event, there will be two more presentations held on January 22 and 29. Here is an agenda of the symposium events:
January 22, 1993
Speaker: E.M. Logothesis
From: Ford Research Lab
Location: Chemistry Building, Room 136
Time: 3:30 p.m.
January 29, 1993
Speaker: Francis W. Wang
From: Polymer Division, National Institute of Standards and Technology, Gaithersburg, MD
Location: Chemistry Building, Room 136
Time: 3:30 p.m.
The symposium on January 30 will run from 8:00 to 12:00, and will include four 20 minute presentations by MSU faculty members engaged in various aspects of sensor research and applications, a psoter session to familiarize symposium participants with sensor related research at MSU; and a wrap-up panel discussion to identify new directions from MSU collaborations in this area. All faculty are invited to participate in the poster session.
January 30, 1993
Synthesis, Development, and Applications of Sensor Materials
Location: Chemistry Building, Room 136
Time: 8:00 a.m. - 12:30 p.m.
8:00 - Students and Post-docs set up posters
8:30 - Development of Recognition Centers for Chemical Sensors
Speaker: Professor Dan Nocera, Department of Chemistry, MSU
9:00 - Technological Applications of Giant Magnetoresistance
Speaker: Professor Peter Schroeder, Department of Physics, MSU
9:30 - The Role and Need for Sensors for the Measurement of Chemical and Physical Properties in Materials Processing
Speaker: Professor Martin C. Hawley, Department of Chemical Engineering, MSU
10:00 - Sensors for Smart Materials Applications
Speaker: Professor Brian Thompson, Department of Mechanical Engineering, MSU
10:30 - Poster Session
11:30 - Panel Discussion
A post doctoral fellow position is available in the School of Textile & Fiber Engineering at Georgia Tech. The candidate will participate in a research project on manufacturing, testing, and theoretical modeling of composites from textile preform structures. A Ph.D. in engineering is required. Desirable experience includes manufacturing, experimental study, and numerical analysis of composites.
The preferred starting date is March 1, 1993, and the duration of the appointment is one year.
Please send full resume, abstracts of publications, copies of transcripts, and a list of three references to Professor Y. Wang, School of Textile & Fiber Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0295. The School of Textile & Fiber Engineering can be reached at (404) 894-2490, or by fax at (404) 894-8780. Georgia Tech is an equal education and empolyment opportunity institution.
By Dr. J.P. Lucas (Associate Professor, Materials Science and Mechanics), Mr. J. Zhou (Research Assistant, Materials Science and Mechanics)
Funded by the Research Excellence Fund
The absorption of liquid penetrants in resin matrix composites affects intrinsic properties of the matrix. Consequently, engineered properties of composites are also affected. Moisture absorption, primarily in the matrix, leads to physical and mechanical degradation of the compostie properties by reducing strength and stiffness of the matrix. Our research involves the determination of moisture effects on fracture processes and on delamination fracture toughness of two classes of continuous- fiber reinforced resin matrix composites, graphite/epoxy and graphite/PEEK (poly ether ketone). While the primary research focus is comprehensive discernment of moisture-induced mircrofracture behavior in composites, considerable attention is given to understanding moisture absorption rate (diffusivity) is found to be significantly higher in thermoplastic matrix composites than in thermoset matrix composites. However, the moisture saturation level (maximum solubility) was notably higher for thermoset resin matrix composites. Regarding fracture analysis, both delamination toughness and fracture energy results were determined as a function of moisture content using double-cantilever beam and modified short bar test specimen methods. Whereas moisture absorption reduced the fracture toughness of the thermoset composite, essentially no effect of moisture absorption was observed on delamination fracture toughness of the thermoplastic composite. Apparently, the reduction in fracture toughness was due to degradation in crack tip craze strength as a result of moisture-induced plasticization of the epoxy matrix. Moisture-induced plasticization of the thermoplastic material is limited. Consequently, degradation in delamination fracture toughness was nil for thermoplastic-matrix composites. Work in progress involves the asessment of sorbed moisture on the physical and mechanical integrity of the fiber/matrix interface.
In order to increase communication between the Composite Materials and Structures Center and its various members, we would like to inform you of upcoming conferences and seminars in the composites arena. Here is a list of some conferences which might be of interest, and deadlines for papers to be presented at those conferences. Brochures on these conferences are available at the Composite Center. Please contact Margie Gray at (517) 353-5466 for any requests.
Tenth Thermoplastic Matrix and Low Cost Composites Review - (low cost processing of advanced organic matrix composites, benefits, major obstacles to applications.)
San Diego, CALIFORNIA
Dates: 2/9-11/93
Abstract due: 7/24/92
International Conference - Advance Composites - (Fabrication, Processing, Properties, Performance, Design & Application)
AUSTRALIA
Dates: 2/15-19/93
Paper due: 4/25/92
Engineering Foundation - Chemical Reaction Engineering: Its Core Components Conference (recent developments in chemical reaction with highlights in the areas: catalysis, kinetics, modeling, reactor design)
PALM SPRINGS
Dates: 2/21-26/93
Society of Automotive Engineers, Conference
DETROIT
Date: 3/1-5/93
Abstract due: 8/20/92
Paper due: 12/21/92
American Institute of Chemical Engineers
HOUSTON
Dates: 3/28-4/1/93
Abstract due: 9/1/92
Paper due: 1/93
Polymer Processing Society
Manchester, ENGLAND
Dates: 4/5-8/93
Abstract due: 9/15/92
Paper due: 1/15/93
Materials Research Society - Technical Symposia, Short Courses, Equipment Exhibit
SAN FRANCISCO
Dates: 4/12-16/93
Abstract due: 11/15/92
The Catalysis Society, 13th North American Meeting
Pittsburgh, PENNSYLVANIA
Dates: 5/2-7/93
Abstract due: 10/1/92
Society of Plastics Engineers, Inc. - ANTEC
NEW ORLEANS
Dates: 5/9-13/93
Abstract due: 8/15/92
Paper due: 11/10/92
Gelellschaft Deutscher Chemiker - 17th International Symposium on Column Liquid Chromatography (recent advances and developments in Column Liquid Chromatography)
Hamburg, GERMANY
Dates: 5/9-14/93
Abstract due: 9/30/92
Fifteenth Symposium of Biotechnology for Fuels and Chemicals
Colorado Springs, COLORADO
Dates: 5/10-14/93
Abstract due: 12/9/92
Society for the Advancement of Material and Process Engineering
Anaheim, CALIFORNIA
Dates: 5/10-13/93
Abstract due: 10/1/92
Paper due: 1/12/93
Qualitative Reasoning-93
Orcas Island, WASHINGTON
Dates: 5/16-19/93
Abstract due: 1/12/93
Paper due: 4/15/93
Third International Conference on Expert Systems for Numerical Computing
PURDUE
Dates: 5/17-19/93
Abstract due: 1/15/93
American Association for Artificial Intelligence-93
WASHINGTON, D.C.
Dates: 7/11-16/93
Abstract due: 1/13/93
9th International Conference on Composite Materials - Industrial Exhibition
Madrid, SPAIN
Dates: 7/12-16/93
American Institute of Chemical Engineers
SEATTLE
Dates: 8/15-18/93
Abstract due: 1/15/93
International Joint Conference on Artificial Intelligence-93
Chambery, FRANCE
Dates: 8/29-9/3/93
Abstract due: 11/1/92
International Conference of Coal Science - 7th Annual Conference (coals potential and environmental knowledge)
Banff, Alberta, CANADA
Dates: 9/12-17/93
Abstract due: 12/31/92
American Institute of Chemical Engineers - FALL
American Society for Composites - 8th Technical Conference of Composite Materials - (All types of composites such as polymeric composites, metal matrix composites, etc.)
Cleveland, OHIO
Dates: 10/19-21/93
Abstract due: 1/15/93
Paper due: 6/15/93
Society for the Advancement of Material and Process Engineering - 14th International European Conference/Expo
Birmingham, ENGLAND
Dates: 10/19-21/93
Society for the Advancement of Material and Process Engineering - 25th International Technical Conference/Tabletops
Philadelphia, PENNSYLVANIA
Dates: 10/26-28/93
The Polymer Science and Engineering Department at the University of Massachuttes, Amherst, seeks applications for positions as Assistant Professors of Polymer Science and Engineering beginning fall 1993 or spring 1994. The Department is a materials department specializing in polymeric materials. The majority of the faculty are synthetic chemists, physical chemists, or physics orientated. The department's intent is to strengthen their engineering program, both in teaching and research, through the addition of another individual that has interests in solid state properties from a continuum, rather than a molecular, physics-engineering or thermodynamics perspective.
One position is sought in the area of polymer engineering with interests in experimental solid mechanics and the other is either in the area of polymer synthesis or the application of nuclear magnetic resonance to polymers. Exceptional candidates with established programs may be considered for appointment with tenure as Professor or Associate Professor. Candidates should send a curriculum vitae, a proposed research program, and arrange to have three letters of recommendation sent to:
William J. MacKnight
Chairman, Faculty Search
Committee
Department of Polymer Science and Engineering
University of Massachusetts
Amherst, MA 01003
The deadline for receipt of applications is February 1, 1993, but the search will continue until suitable candidates are found. All appointments are subject to final budgetary approval. The University of Massachusetts is an affirmative action/equal opportunity empolyer.
By Geoffrey Qui (Graduate Assistant, Materials Science and Mechanics), Kim S. Woo (Graduate Assistant, Materials Science and Mechanics), Dr. Thomas J. Pence (Professor, Materials Science and Mechanics)
Funded by the Research Excellence Fund
Mechanical instabilities leading to sudden structural rearrangement or collapse are of major concern for load bearing structures. The most important example is buckling, in which compressive loads cause the structure to reconfigure itself in such a fashion that it often cannot continue to preform its alloted structural task. Prediction of buckling loads is thus a critical issue for engineering design, unfortunately prediction methods based on experiment are often impractical or too costly due to the geometrical complexity of the proposed structure, as well as the inability to properly scale the response of a prototype when various structural elements display different nonlinear mechanical behavior. Consequently, analytical predictive schemes are of fundamental importance.
From the viewpoint of analysis, the governing equations of equilibrium now have to solutions: one corresponding to a buckled (failed) configuation and the other corresponding to a nonbuckled configuration. Under these circumstances, the actual configuration assumed by the structure is that which minimizes the energy of the system; typically this is the buckled configuration. The predication of buckling is complicated by the existence of these competing solutions. In particular, their coexistance confounds analytical and numerical methods of prediction which, if improperly formated, may tend to select the unstable nonbuckled solution, thus failing to warn the design engineer of a potentially hazardous condition.
Fortunately, methods of analysis have been developed which can, in many cases, accurately predict the onset of buckling in standard structural elements. Unfortunately, buckling and other types of instability, whose behavior is now understood in homogeneous, elastic materials, may drastically alter their character when incorporated in composite structures composed of nonlinearly elastic materials with different stiffness. This research project has as its goal the development of analytical and numerical methods capable of surmounting these difficulties, which in turn will generalize to robust, predictive algorithms capable of driving CAD routines for composite structures.
Recently, our theoretical modeling methods, aided by numerical and symbolic algebra methods, has verified severe changes in nonlinearly elastic plates and panels when laminated composite construction is substituted for non composite construction. In particular, it is often the case that a single ply in isolation develops plane strain buckled solutions that are either of flexural or barreling type. Here flexure is a generalization of the standard buckled solutions in linearly elastic plates whereas barreling has no natural counterpart in the linear theory. Buckled solutions of either type exist for an arbitrary integer number of wavelengths, although each different buckled solution will initiate at a different value of load. Unlike linearly elastic materials, the limit of an infinite number of wavelengths can occur at a finite value of load, so that wrinkling is predicted naturally as one possible buckled state. The critical design issue is the determination of the lowest buckling load from among all of these possibilities. In single plies, this critical instability is often simple mode 1 flexure. However, in layered materials this is not always the case, and we have now identified certain three-ply composite constructions in which wrinkling is the critical mode of failure.
These results underscore the need to refine and extend these predictive procedures. We are currently developing numerical protocols capable of treating systems involving several layers (the complexity of the problem increases like the square of the number of layers). Not only will this enable the prediction of the critical instability in complicated systems, but it will also allow for the assessment of criteria for determining geometrically optimal arrangement of individual laminates within preexisting design constraints.
References:
Buckling Instabilities in a Thick Elastic Three-Ply Composite Plate Under Thrust, T.J. Pence and J. Song, International Journal of Solids and Structures, 27, 1809-1828, 1991.
On the Design of Three-Ply Nonlinearly Elastic Composite Plates with Optimal Resistance to Buckling, J. Song and T.J. Pence, Optimal Design (in press).
Plain Strain Buckling of Layered Neo-Hookean Plates, G. Qui, K.S. Woo, and T.J. Pence, preprint.
The Composite Theory Seminar Series is sponsored jointly by the Composites Materials and Structures Center and the Center for Fundamental Research. The seminars are organized by Phillip Duxbury (517-353-9179) and Iwona Jasuik (517-353-3790). Seminars will begin at 4:00 pm in the Physics-Astronomy Building, room 120. Refreshments will be served at 3:45 in room 224.
Wednesday, February 10, 1993
"Effect of Atomic Scale Impurities on Bonding at the MoSi2/Mo Interface"
Speaker: John R. Smith, General Motors Research Lab
Wednesday, February 24, 1993
"Computational Aspects of Micromechanics: Application of Homogenization Methods"
Speaker: Noboru Kikuchi, University of Michigan
Wednesday, March 31, 1993
"Resonant Ultrasound and the Elastic Moduli of Solids"
Speaker: William M. Visscher, Los Alamos National Lab
Wednesday, April 14, 1993 "Title to be announced"
Speaker: S. Torquato, Princeton University
The Department of Energy (DOE) invites small business firms to submit grant applications under this eleventh annual solicitation for the Small Business Innovative Research (SBIR) program. Firms with strong research capabilities in science or engineering in the areas of basic energy sciences, health and environmental research, high energy and nuclear physics, magnetic fusion energy, conservation and renewable energy, fossil energy, and nuclear energy are encouraged to apply. DOE will support high-quality research or research and development on advanced concepts concerning important energy related scientific of engineering problems and opportunities that could lead to significant public benefit if research is successful.
Objectives of this program include stimulating technological innovation in the private sector, strengthening the role of small business in meeting Federal research and research and development needs, increasing the commercial application of DOE supported research results, and improving the return on investment from Federally funded research for economic and social benefits to the nation. The purpose of a grant application is to provide sufficient information to convince DOE and members of the research community who review the grant application that it is responsive to the subtopic under which it is submitted and that the proposed work represents a sound approach to the investigation of an important scientific or engineering question and is worthy of support under the stated criteria. Experts at institutions such as colleges, universities and DOE contractor operated national laboratories may be consulted during the preparation of the grant application. the grant application should concentrate on research that will contribute to proving scientific or technical feasibility of the approach or concept and would be a prerequesite to further DOE support in Phase II. Where the scientific or technical merit of the innovation has already been established, the work will not be considered for SBIR funding.
Grant applications must be confined to advanced concepts in energy-related scientific or engineering research which may be carried out through fabrication and evaluation of a laboratory prototype where necessary. Phase I research can include innovative design of hardware or software, and the evaluation or optimization of such design, where this is specifically invited under the subtopic description. Specifically excluded from this solicitation are grant applications principally for literature surveys, for compilations of the work of others, for technical assessments, or for technical status surveys. Grant applications principally for the development of already proven concepts should not be submitted, because such efforts are considered the responsiblity of the private sector. Commercialization is the objective of Phase III, where the research supported by DOE under Phases I and II can be continued using non-SBIR funding.
The deadline for grant applications is March 8, 1993. Questions about the DOE SBIR program may be addressed to:
Mrs. Kay Etzler, Program Spokesperson
c/o SBIR Program Manager, ER-16
US Department of Energy
Washington, DC 20585
Telephone (301)903-5867
Requests for copies of the solicitation may be addressed to the SBIR Program Office at the above address, telephone (301)903-5707.
By Rod Andrews (Undergraduate, Chemical Engineering)
This paper received the 1st prize $100 award in the 1992 Student Paper Contest of the Society of Plastic Engineers Student Chapter at MSU.
The accumulating amount of solid wastes generated by consumers is becoming a global problem. Due to the large amount of plastics waste generated in this country and others, the goal of recyclers must be to produce recycled resins that can be used again for their original applications. The present practice of funding alternate uses for impure recycled resins does reduce the total load of plastic entering landfills, but does not address the central problem of reducing the amount of new plastic which enters the waste stream daily.
A significant portion of this plastics waste is poly(ethylene terephthlate) (PET) pop bottles. If PET resin from pop bottles could be recycled and used to produce new pop bottles, the amount of fresh resin entering the waste stream would decline and so reduce the total amount of plastic to be landfilled. Presently, this original use recycling is not done due to the low purity of recycled resins. Manufacturers of pop bottles require PET resins of 99.5% or greater purity, and will then only use recycled resins if they can be obtained less expensively. The problem facing recyclers then is to produce pure resins at low cost. The current method of bottle recycling is a macrosorting technique which does not produce high purity resins. This method consists of sorting collected bottles by type and grinding them to produce flake. This ground flake is then air separated to remove loose label material and cleaned in a hot, mildly alkaline solution to remove any external contaminates and adhesives. The cleaned flake is then put through a hydroclone to separate the lights (HDPE,PP) from the heavies (PET, PVC).
The problem with this process is that it does not separate materials with similar specific gravities. A pop bottle consists of a bottle constructed of PET, a high density polyethylene (HDPE) end-cup, and polypropylene (PP) cap that is lined with poly(vinyl chloride) (PVC). The labeling material is usually also polypropylene. The specific gravities of PET and PVC overlap, causing PET resin produced using the present recycling process and a simple sink-float or hydrocyclone separation would result in an amount of PVC contamination unacceptable for original use recycling. The amount of PVC in the cap liner, were it to enter the PET resin stream, would constitute a contamination of 1.2%, an unacceptably high level.
Due to the relatively high value of PET resin compared to the other materials in a pop bottle, a practical method for recycling would be to discard all other components in exchange for high purity PET product. One possible method of acheiving high purity PET recycle resin is to modify the recycling process to remove the PVC liner from the bottle. A water jetcutting (water knife) stage, which would remove the entire cap, PVC liner, and thread PET bottle top before the bottles were ground is a practical way of doing this that has several advantages. Using a mechanical bottle alignment system and a water knife to remove the cap end of the bottle before grinding would make it possible for present recylcing separation procedures, either sink-float or hydrocyclone separators, to produce recycled PET resin with purity high enough for original use recycling at a low cost, as well as a side stream of reusable HDPE. Water jet cutting systems have been proven to cut both metallic and polymer materials at high rates, and do not produce solvent or oil waste. Water knives also have a higher accuracy for cutting than a mechanical knife.
In this process, some PET material is lost in the cap removal, but this loss is made up by the value of pure PET resin produced. This lost PET constituents 3.7 g, or 7.8%, of the total PET content of the bottle. By removing the cap end of the bottle, a desirable product can be produced efficiently and continuously which has no PVC impurities and which, with the recycling of PET and HDPE, reduces the volume to be landfilled from the bottle by 90.5%.
Although a water knife process does produce some scrap plastic that must be landfilled, it is only 9.5% of the total volume of plastic in the bottle. The process would more than compensate for this by eliminating the continuous feed of fresh plastic into bottles. By developing a process that allows original use recycling of bottle plastic and eliminates the present trend of continually using fresh resin for bottle manufacturing, a significant reduction in the solid wastes produced from consumer plastics can be achieved.
Attention: Amanda Hathaway, CMSCourier Editor, is now connected to the Ethernet system. My EMAIL address is hathaway@msu.edu. You can use my EMAIL to send articles, as well as voice any concerns, suggestions, or requests.
If you have concerns about something that appeared in an issue of the CMSCourier, please notify Amanda Hathaway at (517)353-5466, or by EMAIL address hathaway@msu.edu. The Composite Materials and Structures Center would like to correct any errors we might have made. Also, if you know nayone who would like to be added to our mailing list, please give us their name and address and we will be happy to do so.
Composite Materials and Structures Center
College of Engineering
Michigan State University
East Lansing, MI 48824-1326
Please send any comment or request to
web@cmscsun.egr.msu.edu
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