Composite Material Properties of Hair - Insights from Selective Modification and Characterisation

The project will focus on characterising the nature of human hair and developing new technology to selectively modify the fibre and improve fibre performance. A key element in the project approach is to establish a range of analytical techniques such as Wet Differential Scanning Calorimetry, Scanning Electron Microscopy and the Diastron Tensile Analyser to sensitively probe the surface and bulk properties of the fibre. The hair fibre, like other keratin fibres, has microstructural features that influence the macro-physical and chemical properties of the fibre. These regions contain distinct proteins and lipids that can be degraded or lost from the fibre during washing, bleaching, perming, sunlight exposure and heat styling. By better understanding the effect of selective removal or additions the overall fibre properties can be enhanced. The project will be focused over the duration of the project on key deliverables and the timeline is:
- Removal of free and surface-bound lipids: Year 1. Develop selective lipid removal processes and evaluate surface wettability, friction and adsorption characteristics;
- Removal of free and bound lipids from the cell membrane complex: Year 1. Develop selective lipid removal processes and evaluate flex abrasion, fibre fracture and tensile strength;
- Selective removal of cuticle without changing cortex properties: Year 2. Develop selective cuticle removal processes and evaluate the penetration of dyes, oxidative and reductive chemicals into the bulk fibre without the surface cuticle "barrier" being present. Establish the greater sensitivity of the melanin granules to modification without the cuticle being present;
- Selective removal/replacement of matrix proteins in the cortex: Year 3. Chemical treatments can degrade proteins giving rise to structural damage and loss of quality. The project will develop targeted processes and protective agents that can maintain physical integrity but also evaluate the application of compatible proteins to "repair" the damage;
- Confirm and transfer developed methodologies and knowledge with Unilever: Year 4
- Write up thesis: Year 4