Research subject: The use of hydroxyapatite nanoparticles (HAp) in traditional polymers as reinforcing agent has been reported. While there are a limited number of reports regarding the effect of HAp morphology on the mechanical properties of the polymeric matrix, no research on this effect on supermolecular polymers has been reported so far. This study investigates the hypothesis that incorporation of unidirectionally grown HAp nanoparticles (rod-like nanoparticles, rHAp) into supramolecular polycaprolactone (SPCL) leads to the synthesis of a new bioactive construct.
Research approach: For this, rHAp nanoparticles were first synthesized by microemulsion method and then functionalized with 2-ureido-4[1H]-pyrimidinone (UPy) groups. Moreover, PCL was functionalized and converted to supramolecular structures by reacting the hydroxyl terminal groups with UPy groups. Finally, SPCL/rHAp nanocomposites were synthesized by solution casting method and their structure and properties were examined using attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, scanning electron microscopy (SEM), universal testing machine and simulated body fluid (SBF).
Main results: According to the results, microemulsion is an efficient procedure for the synthesis of rod-like nanoparticles with high phase purity. On the other hand, based on the results, it is possible to functionalize these nanoparticles with UPy. Tensile test showed that by incorporation of these modified nanoparticles into SPCL, a significant increase in both elastic modulus and tensile strength can be observed. In fact, while the initial PCL was a waxy solid, modification with UPy and then incorporation of modified nanoparticles made it an elastic material. Finally, the obtained results indicated high bioactivity of supramolecular nanocomposites compared to the sample without filler. Therefore, supramolecular SPCL/rHAp nanocomposites with bioactive properties and dynamic character can be used as a suitable replacement for bone tissue defects.
Article Type:
Original Research |
Subject:
nano-composite Received: 2021/07/30 | Accepted: 2021/09/13 | Published: 2021/12/22