Enhancing dispersion of hydroxyapatite nanoparticles in polycaprolactone

Superior particle dispersion was achieved for PCL/Si-Zn-HAp nanocomposites leading to enhanced mechanical properties and biological performance. X-Ray μCT was used to quantify and visualise the structural makeup of the composites.

Background:  

The uniform distribution of inorganic filler particles in a polymer matrix is crucial to the final properties of polymer-based composites. Nanoscale particles tend to aggregate in polymer matrices due to size effects and polarity differences, compromising mechanical properties and biological performance. 

In this project an innovative approach to composite preparation is employed, merging novel synthesis techniques with targeted chemical functionalisation of the matrix polymer, to achieve superior dispersion of silicon, zinc co-substituted hydroxyapatite (Si-Zn-HAp) nanoparticles within a polycaprolactone (PCL) matrix. This method enhances the composite’s mechanical and other properties beyond what has been reported in existing literature. 

Support from NXCT: 

The advanced high-resolution 3D X-ray microscopy technology at NXCT was instrumental in visualizing and quantifying particle distribution in our composites. This technology allowed us to evaluate the degree of nanoparticle agglomeration across different sample conditions, providing critical validation for our novel preparation and functionalization techniques. The assistance and expertise of Tristan Lowe in X-ray µCT operation and data processing using image segmentation algorithms as well as visualization using ORS Dragonfly, proved invaluable. 

Future Research: 

The insights gained from the studies conducted at the NXCT will allow us to correlate changes in particle distribution and agglomerate size with mechanical and biological properties. This understanding is crucial for optimizing composite performance for various applications, including biomedical devices and advanced manufacturing.