University of Houston, USA, researchers have recently developed and verified a new route for synthesizing superior forms of entangled or knotted polymers with pre-designed characteristics for use in applications such as drug delivery and smart coatings. Using a Viscotek 270max triple detector gel permeation chromatography (GPC) system from Malvern Instruments, the Houston team successfully confirmed the innovative synthesis of interlocking polymer rings (catenanes) by atom transfer radical polymerization (ATRP) from templated initiators. By combining refractive index (RI), viscosity and light scattering detection, the 270max provides reliable molecular weight data and easy detection of the degree of synthesis throughout the method development, as well as verifying the character of final polymers imaged using atomic force microscopy (AFM).

 “The Viscotek 270max is critical to verifying this new method of polymerization,” explained Professor Rigoberto Advincula, Department of Chemistry, University of Houston. “These are high-molecular-weight polymers, and ring closure is a thermodynamically difficult reaction that must be done under dilute conditions. Using the triple detection offered by 270max, we were able to effectively characterize the molecular weight of our sample and detect the degree of ring closure versus the amount of non-closed polymer.”

The University of Houston’s initial success implies that it will be possible to synthesize superior knotted polymers for applications in coatings, lubricants and surface modifiers, among others. In terms of polymer theory, Professor Advincula’s team also plans to make catenated and knotted block co-polymers. The project has been funded by the National Science Foundation (USA).

The Viscotek 270max from Malvern Instruments is a complete, advanced, multidetector GPC/SEC system suitable for all macromolecular applications, particularly research. Further information can be found at

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