Prabhakar, RL;
(2008)
Characterisation of novel degradable polymers and polymeric systems.
Doctoral thesis , UCL (University College London).
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Abstract
Novel polymers, composites and blends were prepared, and their properties were characterised using a variety of characterisation methods to evaluate their potential as biomaterials. Two sets of four polymer composites were created with particulate phosphate glass as the filler material, with varying calcium contents. Addition of glass reinforced the polymer as the stiffness of the composites was shown to significantly increase. PCL composites all lost a percentage of their initial weight and stiffness (depending on the calcium fraction of the glass) soon after being placed into aqueous solution. The pH of the surrounding solution was shown to become more acidic with increasing percentages of calcium content. The rate and level of ion release was also dependant on the glass composition, but the pH effects caused the 28 and 32 mol% composites cation release to overlap. A library of novel serinol polyesters was characterised. These were all amorphous polymers, whose DSC traces displayed glass transitions only. Correlations were observed between structure and the wettability of polymer surfaces. No cells were shown to attach onto the flexible pendant chain polymer surfaces, which also possessed very low glass transition values. Diphenol polymers were evaluated as homopolymers and blends. The homopolymers displayed structure-property variations, but these were not so apparent in the blends. Addition of polyacetal to PLA improved the flexibility of PLA. A correlation was observed between loss-modulus and the wettability of the blends. Finally, isothermal crystallisation was introduced as a specialised DSC characterisation tool for degradable polymers. The crystallisation properties of PCL were analysed, and the effects of blending PLA on PCL crystallisation were evaluated. Low molecular weight semi-crystalline PLA was shown to significantly affect both the crystallinity and the crystallisation processes of PCL. High molecular weight amorphous PLA did not affect the crystallinity of PCL, yet was shown to affect the crystallisation process of PCL.
| Type: | Thesis (Doctoral) |
|---|---|
| Title: | Characterisation of novel degradable polymers and polymeric systems |
| Identifier: | PQ ETD:593395 |
| Open access status: | An open access version is available from UCL Discovery |
| Language: | English |
| Additional information: | Thesis digitised by ProQuest. |
| URI: | https://discovery.ucl.ac.uk/id/eprint/1446066 |
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