Development of multifunctional Polyether Ketone (PEEK) composites

Abstract

Manufacturing techniques such as injection moulding (IM) and extrusion are widely used as robust methods of producing complex parts and blends of polymers and polymer composites. Polymers generally are poor thermal conductors, due to the molecular make up and crystal structures, therefore research has been conducted to improve conduction. Polyether ether ketone (PEEK) is a polymer of significant interest due to temperature resistance and mechanical properties.

In this study nickel and iron particles were melt blended with PEEK to evaluate the properties of the metal particle reinforced polymer composites for thermal conduction. Two different particles sizes of iron and one particle size of nickel were studied. Iron at 5 µm and 45 µm and nickel at 5 µm were characterised. The changes in thermal conductivity were reported with base resin reported at 0.24W/mK and 30% of metal reinforcement values being improved to 0.36 W/mK for 5µm iron, 0.46 W/mK for 45µm iron and 0.42 W/mK for nickel. The results for nickel and larger particles iron were also reported at 35% weight loading at 0.48 W/mK and 0.68 W/mK. The dispersion of particles was studied using scanning electron microscopy (SEM), FTIR was used to analyse the chemical changes in composites.

Differential scanning calorimetry (DSC) evaluated the crystallisation properties of different composites, showing a change in the crystallisation behaviour upon different processing temperatures. Injection moulded samples were held at two different mould temperatures of: 190 °Cand 80 °C to study processing conditions. Thermal gravimetrical analysis (TGA) analysed the thermal breakdown and changes in thermal breakdown for metal particle reinforced polymers composites, with nickel showing a decrease in onset temperature. Isothermal crystallisation showed the changes in polymers crystalline regions, which was then furthered studied by hot stage microscopy and SEM. This showed crystalline changes at high loadings of metal particles.

Thesis is embargoed until 30th April 2026

Date of Award	Apr 2024
Original language	English
Sponsors	Special EU Programmes Body
Supervisor	Atefeh Golbang (Supervisor) & Edward Archer (Supervisor)