Pickering emulsions as enabling platforms for designer polymer-based hybrid materials

Pickering emulsion templates provide highly promising alternatives to construct advanced, polymer-based, hybrid materials with new or enhanced functions. In this Thesis, Pickering emulsion templates were used to obtain polylactic acid (PLA) composites with well dispersed, fully biodegradable nanocellulose. The Pickering emulsion templating approach offers a versatile route to disperse hydrophilic CNCs, with and without surface modification, in the hydrophobic PLA matrix. The rheological, thermal, and mechanical properties of PLA/nanocellulose composites with different nanocellulose content up to 15 wt.% are elucidated in detail. Furthermore, the enzymatic degradation of PLA/nanocellulose composites was studied using the lipase from Candida rugosa and proteinase K from Tritirachium album. The application area of the PLA/CNC composites as foamed insulating materials was broadened by using a CO2 batch process with relatively mild operating conditions. In a next step, we exploited modified CNC particles to prepare functional hybrid materials with designer colors. We used dyed-nanocellulose to color polymethyl methacrylate (PMMA). PMMA was selected for its high transparency. The thermal and mechanical properties of the corresponding-colored composites were thoroughly investigated. In addition, the colored PMMA composite possessed good transparency. Finally, phase change emulsion gels consisting of two types of phase change materials were constructed using the excellent stability of Pickering emulsion templates. The gels exhibit some distinctive properties, including high stability, non-flammability, shape memory, and good mechanical properties, and have been explored as an environmentally friendly building thermal management system in model experiments. The materials synthesized and studied in this Thesis prove the great potential of the Pickering emulsion approach to obtain advanced engineering materials for the next generation “green” plastics.