The development, application and understanding of structure-mechanical property relationships associated with the synthesis of CANs using various reversible chemistry systems

Grantham Scholar Jennifer Hughes’ project addresses the need in various industries for reusable composite materials in order to reduce waste.

The project

My project focuses on the structure-mechanical property relationships associated with different types of covalent adaptable polymer networks (CANs). I will look at how these can be applied in industrial applications, such as thermally reversible adhesives, coatings and elastomers.

CAN structure will be analysed using techniques including 1H NMR, GPC, FTIR. Mechanical properties will be evaluated using Rheology, Differential Scanning Calorimetry (DSC), Tensile strength etc.

Sustainability problems this project addresses

A key problem with current recycling systems is that they are designed for mono materials rather than composites. Consequently, for many years, and in the UK in particular, tons of non-biodegradable composite waste has been incinerated or sent to landfill. Further, the use of composite materials is rapidly growing, because their applications span many industrial sectors, e.g. automotive, aerospace, and renewable energy.

In order to make composites more sustainable, one goal of my project is to design and develop an adhesive, coating or elastomer that can be triggered by external stimulus such as heat to debond (i.e. thermally reversible).

A potential strategy to reverse the adhesion process is to join the individual layers of a composite with an adhesive that can be debonded at the end of service life. This would facilitate separation of constituent materials and so enable recovery of the separate raw materials for re-use or recycling. Both re-use and recycling would be environmentally beneficial as they reduce the impact of the materials.

Recently, there has been a growing interest in adhesives which possess thermally reversible crosslinking networks. Such systems aim to provide strong mechanical properties during use due to high crosslinking densities. But they can undergo a significant loss in modulus at specified temperatures due to the breaking of crosslinks to facilitate separation.


Free sustainability webinars. Jennifer was part of a group who organised the Rewilding: Plant it and They Will Come webinar. Created as part of our ongoing public engagement, it is on of a playlist of Grantham Scholar webinars available on YouTube.

Social media

You can find Jennifer Hughes on LinkedIn.

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