Size does matter. Size does matter.
Big molecules...pose big
characterization problems. The traditional chemical methods--NMR,
IR, UV-Vis, single crystal X-ray, and mass spectroscopy--are often powerless
when it comes to structural determinations of polymers with molec
ular
masses of several tons per mole. Also, the use of polymers to make macroscopically
large structural assemblies requires special materials characterization
techniques. Most of the equipment at LSU for polymer characterization
is located in Chemistry's Polymer Analysis Laboratory (PAL) or Chemical
Engineering's Polymer Engineering & Processing Laboratory (PEP). Additional
equipment is found in the LSU's Textiles Laboratory, Peptide Facility,
Mass Spectrometry Facility and the M.D. Socolofsky Microscopy Facility.
Training manual and instructional materials are available for some of the equipment in PAL, PEP and the other facilities.
PAL (Department of Chemistry)
- Light Scattering
- Viscometry
- Gel Permeation Chromatography
- Optical Microscopy
- Thermal Analysis
- Porosimetry
- Langmuir Blodget Techniques
- Analytical Ultracentrifugation (operated by the Department of Biological Sciences' Peptide Facility)
- MALDI-TOF and Electrospray MS (operated by the Chemistry Department's Mass Spectroscopy Laboratory)
- Electron Microscopy (in the M.D. Socolofsky Microscopy Facility)
- Small angle X-ray scattering (coming soon to LSU's Synchrotron Storage Ring)
The Chemistry Department's Polymer Analysis Laboratory (PAL) serves polymer/biopolymer researchers across the LSU campus, as well as industrial clients and researchers from other Louisiana universities. PAL coordinates with other labs on campus, including especially the Mass Spectroscopy Facility, the M.D. Socolofsky Microscopy Facility, Textiles Laboratory and the Peptide Facility. Students have easy "hands-on" access to almost all PAL facilities.
For polymer analysis at the molecular level, the mass, size, and aggregation characteristics of polymers may be characterized on either of two state-of-the-art laser light scattering systems built to the specifications of the department in LSU's Scientific Instrumentation Shops. Distribution of polymer molecular weight can
be measured qualitatively or absolutely on one of two Waters-Wyatt GPC systems equipped with multiangle laser light scattering detectors. One can also use the newly arrived Viscotek TA60 triple detection system, which combines light scattering and viscometry in a
GPC system. Does your polymer have too much freedom? Try constraining it to two dimensions on the NIMA Langmuir Blodget trough, equipped for surface pressure measurement and production of thin films.
At the supramolecular level, a wide range of equipment is available. Pal's thermal analysis facility, featuring equipment from TA Systems and Seiko, includes differential scanning calorimetry
(DSC--three instruments), simultaneous thermogravimetric/differential thermal analysis (TGA/DTA--two instruments), steady state and oscillatory thermomechanical analysis (TMA), and dynamic mechanical spectroscopy (DMS). The DSC's have adequate sensitivity for many polymer solutions, as well as bulk polymers. Even more sensitive solution and titration calorimeters are available elsewhere on campus. DMS samples can be tested in tension, shear, or bending using film, fiber, or bulk samples Flow properties of melts and solutions can be studied on a soon-to-arrive Rheometrics ARES rheometer or on the Bohlin Constant Stress rheometer located in PEP.
PAL's optical microscopy facility is equipped for polarized, Normarski, transmission, and epi-fluorescence illumination, as well as confocal mode for "optical sectioning" of materials in three dimensions. A special apparatus for fluorescence photobleaching recovery combines laser illumination and computer-interfaced photometry to measure diffusion rates in solutions, gels, melts, and liquid crystals. Film and video cameras interface to two separate image processing systems. The user can print high-quality images through the ethernet on one of two Tektronix Phaser printers.
If all this isn't enough, see our friends! Velocity and equilibrium analytical ultracentrifugation studies of mass, size, shape and aggregation can be performed on a Beckman XLA, located in the LSU Peptide Facility. Try your luck at a really precise molecular weight with Matrix Assisted Laser Desorption Ionization/Time of Flight Mass Spectroscopy, located in Chemistry's Mass Spec facility. Or get an electrifying picture of what's going on in the Socolofsky Microscopy Facility, where a complementary optical microscopy facility also illuminates small features. Delicate structures, such as complex fluids, can be viewed in the freeze-fracture or cold stage microscopy facilities in yet another electron microscopy facility. Or try your "hand" on the Kawabata apparatus in the Textiles Laboratory, which is one of several places around campus where tensile and other mechanical testing can be performed.
PEP (Department of Chemical Engineering)
- Mixing
- Extrusion
- Co-extrusion
- Fiber Spinning
- Film manufacture
- Injection Molding
- Rheology
- Wet Scanning Electron Microscopy
The Department of Chemical Engineering's Polymer Engineering and Processing Laboratory (PEP) contains additional tools for material and process development as well as analysis:
- HAAKE RHEOMIX-600: This mixer is equipped with Roller,Cam, Sigma and Banbury rotors for evaluation of mixing variables and preparation of laboratory quantities of polymer blends that require large shearing forces.
- Berstorff Twin Co-rotating Screw Extruder-ZE 25: This 25mm diameter screw extruder features interchanging screw elements, segmented barrels and an L/D of 28/1. Typically this machine is used for preparing laboratory amounts of polymer blen ds under variable temperature and shearing conditions.
- Plastimac Co-rotating Twin Screw Extruder: This 38.1mm diameter screw extruder also features interchanging screw elements, segmented barrels but with an L/D of 12/1.
- Pilot Scale Continuous Atmospheric Reactor: This is a single screw reactor used for thermal shearing and delignification in order to obtain pilot plant quantities of fibrous materials for woven and non-woven geotextile mats and products.
- Coextrusion line that is used for obtaining pilot plant quantities of two polymer melts.
- PHI - Precision Press-TS-21-H-C(4A)-5: This is an air actuated press with independent heating/ cooling for each platen. This press provides control of the closing speed, clamping force and cooling rate. This press is used to study pr ess cycle variables of polymeric materials and blends.
- Arburg Allrounder Injection Molding Machine-170 CMD 150-45: This reciprocating unit is used to study injection moulding variables using laboratory quantities of materials for low-scale production.
- Hi Tech reaction injection molding machine: This molder is used for studying the processing variables associated with production of laboratory quanties of molded parts derived from a reaction injection molding process. The current sy stem is set up to produce polyurethanes that are reinforces with different types of fibers.
- A fiber coating line equipped with a special coating die along with chemical baths and take-up device. Currently this line is currently set up for modifying the surface characteristics of nylon fibers.
- Kruss Processor Tensiometer and Single Fiber Measuring System-K14/K141: This machine is used for characterizations of contact angle, surface tension, surface energy, liquid densities as well as absorption properites and diameters of fibers.
- Bohlin VOR Rheometer: Characterize rheological properties of polymer and polymer blends under a variety of stess, strain and flow conditions.
PAL Facility Directors
- Dr. Ioan I. Negulescu, (225) 578-4468: ioan.negulescu@chem.lsu.edu
- Dr. Paul S. Russo, (225) 578-5729: paul.russo@chem.lsu.edu
- Dr. William H. Daly, (225) 578-3237: bill.daly@chem.lsu.edu
PEP Facility Directors
- Dr. Kerry Dooley (225)578-3063: dooley@che.lsu.edu
We're Easy!
Accessibility: Of course, students and postdocs get to use all these great facilities after appropriate training. But the same is true of our industrial collaborators! If you are an industrial client, one of the best ways to avail yourself to MSG facilities is just to camp out here and let us work with you. Our students learn a lot from industrial visitors, and you can find some great future hires.
Speed: MSG employs a full-time Ph.D. technical staff to see that jobs are done in timely fashion.
Cost: MSG has adopted very flexible policies to make it possible for our industrial clients to use the facilities at low cost. Call any of the directors above for details.
Advertise! Some of the equipment in PAL and PEP was donated by vendors eager to place equipment in the hands of students and future customers. Other vendors find our site an ideal location for demos. Instead of carting equipment hither and yon, to this meeting and that, consider running a minicourse at our site near so many potential buyers . Or let us do it. In conjunction with the Baton Rouge Section of the Society of Plastics Engineers, MSG teaches minicourses on our available equipment. A typical class would include 30-40 employees from area and distant companies. These may become future customers!