Size-Exclusion Chromatography
Instrument Manager: Eric Dailing; Alternate: Brett Helms
Malvern Panalytical’s OMNISEC is a Size Exclusion Chromatography (SEC) system for the measurement of absolute molecular weight, molecular size, intrinsic viscosity, branching, etc. for synthetic polymers. The Organic Facility hosts two OMNISEC systems, one employing THF as the mobile phase, and one employing DMF (with LiBr). Choice of system and associated mobile phase will depend on the chemistry of the polymer: THF is commonly used for styrenics, poly(meth)acrylates, polyesters, some polycarbonates, and some polyethers (not PEO or PEG); DMF is commonly used for poly(meth)acrylates, poly(meth)acrylamides, polyamides, polyurethanes, polyvinylpyridines, polycarbonates, polyethers, polyimides, etc. Neither system should be used with polyelectrolytes, polyionic liquids, etc.
TOSOH’s High Temperature GPC System is used to analyze molecular weight distributions in polymer samples that are only soluble at high temperature in chlorinated aromatic solvents (e.g., ODCB, TCB, etc.), such as for polyolefins, or pi-conjugated organic semiconducting polymers. The instrument is typically operated at 120–150 ˚C. The instrument features a dual pump system, dual flow RI detector, spacious column oven, total system temperature control, and autosampler.
Dynamic Scanning Calorimetry (DSC)
Instrument Manager: Steve Shelton; Alternate: Liana Klivansky
A TA Instruments Q200/RCS90 DSC (with Modulated DSC) allows for characterization of material thermal properties such as glass transition, melting and crystallization, phase changes, product stability, as well as heat capacity in the temperature range of –90 °C to 400 °C.
Spectroline XL-1500 UV Crosslinker
Instrument Manager: Eric Dailing
The crosslinker operates at 254 nm and 365 nm, and at 90W.
Rheometer
Instrument Manager: Eric Dailing
The TA DHR-2 is a rheometer equipped to measure viscosity of liquids or suspensions, and viscoelastic properties of polymers including shear modulus, creep compliance, and stress relaxation. Parallel plate and cone-plate geometries are available. The instrument has a peltier stage with a temperature range of –20 to 150 ºC.
