Polymer networks constitute many of the most important industrial materials such as thermosets, elastomers and gels, with annual global production estimated at 65 million tons. Hydrogels are water-swollen networks of crosslinked hydrophilic polymers which are used in everyday personal care products such as superabsorbents, contact lenses or wound dressings, as well as in emerging advanced applications, e.g., controlled drug delivery systems, tissue engineering and 'smart' stimuli-responsive (bio)materials.
Similar to other polymer networks, the vast majority of hydrogels are one-component, i.e. consist of one type of polymer. This is due to the nature of the crosslinking process, which produces randomly crosslinked insoluble gels, difficult for further modification. Consequently, the range of properties accessible in conventional networks/hydrogels is limited by the choice of the polymer. Thus, in order to synthesise functional hydrogels with tuneable properties as well as the ability to independently respond to multiple stimuli such as temperature or pH, novel, unconventional network architectures need to be developed.
This project will seek to introduce a new type of hydrogels, and, more generally, polymer networks, composed of two different polymers combined within a single network, referred to as cross-copolymer networks (CCN). In CCNs, two polymers are synthesized and crosslinked in a sequential manner, allowing to independently control the parameters of each 'half' of the network. Proof-of-concept studies on the synthesis of CCN hydrogels will be undertaken to investigate their internal structure and physical properties. Model stimuli-responsive hydrogels with a CCN architecture will be synthesized to evaluate the impact of the internal structure on thermal and/or pH-induced phase transitions. The ability to precisely tune the CCN hydrogel's phase transitions will allow better control over their mesh size and transport properties resulting in new biocompatible materials for controlled drug delivery, 'smart' wound dressings, and other biomedical applications.