This document describes the GPC viscometry analysis of Polydimethyl Siloxane (PDMS) using the Agilent 390-MDS Multi Detector Suite. PDMS is a non-toxic, non-flammable, silicon-based polymeric material known for its unusual rheological behavior. It behaves like a liquid with long flow times or at low temperatures. PDMS is produced in various grades, from liquids to rubbery semi-solids, depending on the molecular weight of the constituent chains. PDMS is widely used in silicone caulks, lubricants, damping fluids, heat transfer fluids, as well as breast and knuckle implants. It is also used as a food additive with the E number E900, functioning as an anti-foaming and anti-caking agent. The inclusion of a viscometer and refractive index detector in the detector array allows for analysis using the universal calibration method, providing accurate molecular weights independent of the calibration standards used. Toluene is preferred over tetrahydrofuran (THF) as the solvent for PDMS analysis due to its isorefractive nature. The 390-MDS was chosen for its ability to perform multi-detector analysis.
The document details an analytical method for characterizing Polydimethyl Siloxane (PDMS), a silicon-based polymeric material used in various applications including lubricants and implants. Due to PDMS being isorefractive with tetrahydrofuran, the analysis utilizes Toluene as the eluent.
| Columns | 2x Agilent PolyPore, 300 x 7.5 mm |
|---|---|
| Eluent | Toluene |
| Flow Rate | 1.0 mL/min |
| Injection Volume | 100 pL |
| Detector Temp | All detectors set at 60 °C |
Toluene is preferable because PDMS is isorefractive with tetrahydrofuran, making THF unsuitable for analysis.
The method requires a flow rate of 1.0 mL/min and an injection volume of 100 pL.
All detectors in the train must be set to a temperature of 60 °C.