Development and properties of polycaprolactone/hydroxyapatite composite biomaterials

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Materials Engineering

Background:

• Polycaprolactone (PCL) and hydroxyapatite (HA) are widely used in biomedical applications.
• Developing robust PCL/HA composites with enhanced properties is crucial for tissue engineering and drug delivery.
• Understanding the influence of processing methods on composite performance is essential.

Purpose of the Study:

• To compare two distinct methods for preparing PCL/HA composites: conventional blending and surface grafting.
• To evaluate the mechanical properties, water uptake, and degradation behavior of the prepared composites.
• To determine the optimal preparation method for reducing water susceptibility in PCL/HA composites.

Main Methods:

• Conventional blending of PCL and HA using an extruder.
• Ring-opening polymerization of caprolactone initiated by HA surface hydroxyl groups to graft PCL onto HA.
• Tensile testing in dry and wet states to assess mechanical properties.
• Scanning electron microscopy (SEM) for interface analysis.
• Water uptake and weight loss experiments for degradation studies.

Main Results:

• Both preparation methods showed an increase in modulus with higher filler content.
• Mechanical properties significantly decreased in the wet state for both composite types.
• The decrease in mechanical properties was more pronounced in conventionally blended composites compared to grafted composites.
• Grafting PCL onto HA resulted in lower water susceptibility.

Conclusions:

• Surface grafting of PCL onto HA is a superior method for producing PCL/HA composites with reduced water susceptibility.
• This approach enhances the durability and performance of PCL/HA composites in aqueous environments.
• The findings suggest that surface modification is a key strategy for optimizing PCL/HA composite applications.