Polylactic acid nanocomposites for biomedical applications: effects of calcium phosphate, and magnesium phosphate nanoparticles concentration

Abstract

Biodegradable polylactic acid (PLA) is synthesised from lactic acid by ring-opening polymerisation (ROP). Calcium phosphate (CaP) and magnesium phosphate (MgP) nanoparticles were incorporated into the PLA matrix to study its mechanical and rheological properties. PLA nanocomposites were prepared by the melt compounding assisted with ultrasonic vibration, and the samples were cast inside the vacuum chamber. Scanning electron microscopy photomicrographs of PLA nanocomposites show that CaP and MgP nanoparticles were well dispersed inside the matrix. The tensile strength of PLA/CaP nanocomposites increases up to 15% loading and that of PLA/MgP nanocomposites up to 2% concentration. It is also found that with respect to tensile strength, PLA/CaP and PLA/ MgP nanocomposites can be used for the human bone implant. Rheological properties show that complex viscosity decreases with angular frequency but increases with nanoparticles concentration, confirming shear thinning behaviour.Storage modulus and loss modulus of PLA nanocomposites increase with angular frequency and nanoparticles concentration.

Factors Affecting Mechanical Properties of Reinforced Bioplastics: A Review

“…The relative proportions of the filler materials in the formulation dictate the mechanical properties of the composites [68,77]. Various studies were undertaken on the effects of filler on the mechanical properties of biocomposites with different filler contents, and it can be said that aggregation phenomena are more evident for specimens at high filler loading [24].…”

“…Various studies were undertaken on the effects of filler on the mechanical properties of biocomposites with different filler contents, and it can be said that aggregation phenomena are more evident for specimens at high filler loading [24]. In the study of calcium phosphate (CaP) and magnesium phosphate (MgP) nanoparticles' impact on pure PLA by Sahu et al [77], the tensile strength of PLA nanocomposites increases linearly with the inclusion of CaP concentration up to 15 wt%, with a subsequence decrease in tensile strength at 20 wt% of fibre concentration. According to their team, this increase in tensile strength is related to the presence of a tensile stress-carrying filler in the polymer matrix.…”

Calcium Phosphate Loaded Biopolymer Composites—A Comprehensive Review on the Most Recent Progress and Promising Trends

“…The in vitro tests on the fibers confirmed the formation of apatite phases on their surface, and they were also biocompatible. Sahu et al [142] synthesized biodegradable PLA from lactic acid monomers by ring-opening polymerization (ROP). Calcium phosphate and magnesium phosphate nanoparticles were embedded into a PLA polymer to examine their mechanical and rheological characteristics.…”

An Overview of Enhancing the Performance of Medical Implants with Nanocomposites

“…In addition, CNTs can also impart electrical conductivity to the polymer, which can be useful for some implant applications. Other polymer-based nanocomposites that are being investigated for medical implant applications include polylactic acid (PLA) reinforced with nanoparticles [53,54] and hydroxyapatite nanoparticles dispersed in polyethylene glycol (PEG) [55] for bone tissue engineering.…”