Tetra-detection GPC/SEC unlocks the secrets of branched copolymers

A new applications poster entitled 'Characterisation of branched copolymers by tetra detection GPC/SEC' is now available by contacting Viscotek.

Using samples provided by Unilever Research and Strathclyde University, UK, the authors discuss characterisation of polymers that are complex both in terms of structure and composition which present many difficulties for conventional GPC/SEC techniques.

In the report the analysis of 4 copolymers samples (1 linear and 3 branched) on a Viscotek Tetra Detector system with OmniSEC software is discussed. Results are presented showing how molecular weight, intrinsic viscosity and molecular size data was obtained directly and how using the OmniSEC software the amount of branching was determined in the 3 samples relative to the linear reference. Ratioing the response from the two concentration detectors (RI and UV) the authors were also able to determine chemical composition differences in the branched samples.

Combining the power of RI, UV, Viscometry and Low Angle Light Scattering (LALS) detectors acting together, with each detector providing complimentary but different information, the Tetra Detector from Viscotek is the most powerful GPC/SEC system available today. When integrated with the GPCmax (pump, autosampler, degasser) and OmniSEC software the Tetra Detector system is able to cope with even the most demanding analyses.

By ratioing the response from the two concentration detectors the system corrects the limitations of using a single detector by delivering rapid determination of a true copolymer concentration profile. Using the viscometry and LALS detectors the Tetra Detector system enables users to obtain absolute molecular weight, molecular size (to less than 1 nm) and intrinsic viscosity as well as information on branching, conformation, aggregation and composition from their sample. Maintained in a thermostatically controlled environment the Tetra Detector system has the sensitivity and stability to repeatably characterise copolymers and conjugated proteins even at low concentrations.

Malvern Instruments acquired Viscotek in January 2008.