Analytical techniques

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Techniques to measure Molar Mass Distributions

Size based liquid chromatography hyphenated with intelligent detection

GPC/SEC/GFC and HT-GPC Services

PSS uses GPC/SEC/GFC to measure the molar mass distribution.

Mobile Phases
Detection (Standard)*
Detection (Options)*
Hyphenation

Typical mobile phases are

Tetrahydrofuran, THF
Toluene
Choroform
Dimethylformamide, DMF
Dimethylacetamide, DMAc
Dimethylsulfoxide, DMSO
N-Methyl-2-pyrrolidone, NMF
Hexafluoroisopropanol, HFIP
Trifluoroethanol, TFE
Trichlorobenzene, TCB
Diclorobenzene, DCB
Water
PBS

If required salts or modifiers will be added to ensure for interaction free size separation.

Ambient GPC/SEC/GFC

Differential Refractive Index Detection, RI or, if possible, UV/VIS at specific wavelength

High Temperature GPC

Infrared Detection, IR (specific wavelength CH₂, CH₃ or C=O) or Differential Refractive Index Detection, RI

*without brand/manufacturer information: different brands/manufacturers available

Ambient GPC/SEC/GFC

UV/VIS detection (specific wavelength) or DAD/PDA (spectra)
Right Angle Light Scattering (Multi color), PSS SLD1000
Dual Angle Light Scattering detection, PSS SECcurity MDS
Dynamic Light Scattering detection, PSS BioSECcurity MDS
7 angle Multi Angle Light Scattering, PSS SLD7100
Viscosity detection, PSS DVD1260 viscometer
Triple plus detection, DVD1260 viscometer and SLD7100
Fluorescence detection (specific wavelength or spectra)
Thermo Fisher EXQ ESI sprectrometer

High Temperature GPC

HT-Evapoarative Light Scattering Detection, PSS GPC 220 SECcurity² ELSD
Dual Angle Light Scattering Detection
Viscosity,

*without brand/manufacturer information: different brands/manufacturers available

GPC/SEC/GFC searations can be hyphenated with:

static light scattering (right angle, dual angle, multi angle)
dynamic light scattering
triple detection
viscometry
FTIR (in solution/flow mode)
FTIR (evaporation mode/LC Transform)
Mass spectrometry - ESI
Mass spectrometry - MALDI

PSS provides GPC/SEC/HT-GPC in different mobile phases at temperatures up to 155°C to compare samples and to obtain molar mass averages and molar mass distributions. In accordance with the requirements of each individual application, we employ various instrument setups, configurations and detectors. The analysis fee for the first sample includes calibration, validation and verification of the system according to the PSS quality system.

Techniques to measure Chemical Composition

Interaction Chromatography and 2D Chromatography

IPC and 2D Services

PSS applies different Interaction Polymer Chromatography (IPC) techniques to investigate chemical composition distributions.

Techniques applied
2D Chromatography

Interaction Polymer Chromatography (IPC)
- Isocratic/Gradient Chromatography
- Chromatography under Critical Conditions
- Chromatography under Limiting Conditions
SEC-Gradient
Temperature Gradient Interaction Chromatography (TGIC)
Temperature Rising Elution Fractionation (TREF)

2-dimensional chromatography allows for in-depth characterization. PSS operates instrumentation to offer the following techniques

offline 2D setups
- Fraction collection using fraction collectors
- Fraction collection using storage loops
online 2D setups
- heart-cutting approach
- comprehensive approach with
  - < 52 transfer injections per sample
  - < 100 transfer injections per sample
  - < 250 tranfer injections per sample

In contrast to GPC/SEC Interaction Polymer Chromatography (IPC) allows for separations based on chemical composition or end groups. This service involves an initial consultation with our analytical services staff to determine the most effective analytical methods to use. In accordance with the requirements of each individual application, we employ various instrument setups, configurations and detectors. IPC techniques can be hyphenated with GPC/SEC/GFC to allow for 2-dimensional separations.

Techniques for Identification and Determination of Material Properties

Spectroscopy, Mass Spectrometry and more

Services for Identification and Material Properties Determination

NMR
Light Scattering
FTIR/ATR-IR
DSC
TGA
EA
MALDI-ToF

Nuclear Magnetic Resonance Spectroscopy (¹³C, ¹H)
NMR provides detailed structural information on macromolecules and is used to determine

Monomer types
Tacticity
M_n, number avergage molecular weight
End groups
Co-monomer ratios

Static light scattering

SLS measures the intensity of the scattered light at one or more (different) scattering angles and is used to determine

M_w, weight avergage molecular weight
A₂, Second virial coefficient
R_g,z, z-averaged radius of gyration

Dynamic light scattering

DLS measures the time dependency of the intensity of the scattered light. It is used to determine

R_h, hydrodynamic radius

Fourier Transform Infrared Spectroscopy Analysis/ Attenuated Total Reflection Infrared Spectroscopy
FTIR is mainly used to measure spectra from unknowns. The spectra are compared with reference spectra in a libary to aid identification.
ATR is a sampling technique used in conjunction with IR which enables samples to be examined directly in the solid or liquid state without further preparation.

Differential scanning calorimetry
DSC measures the difference in the amount of heat required to increase the temperature of a sample and a reference as a function of temperature. It is mainly used to determine

Melting point/range
Heat Capacity
Thermal stability
Decomposition Temperature
Glass Transition

Thermogravimetric Analysis
TGA measures changes in the weight of a sample as a function of temperature and/or time. It is used to determine

Degradation temperatures
Residual solvent
Moisture content
Amount of fillers in composite material compositions

Elemental Analysis

Matrix Assisted Laser Desorption Ionization (MALDI) - Time of flight

In contrast to fractionating (chromatographic) techniques batch techniques provide average values but no distribution information. A variety of batch methods is used to investigate macromolecules and proteins and to determine material properties such as thermal properties.