Physico‐chemical, thermal, and mechanical properties of PLA‐nHA nanocomposites: Effect of glass fiber reinforcement

Abstract

In this study, tri‐layered composites were prepared by reinforcing poly‐lactic acid (PLA) nano‐hydroxyapatite (n‐HA) (1 and 5 wt%) and 20 mol% continuous phosphate glass fibers (PGF). Initially, the effect of addition of 1 and 5% n‐HA on the structural, thermal, mechanical, and thermo‐mechanical properties of 100% PLA was investigated. With 5 wt% n‐HA addition the tensile modulus (TM), flexural modulus (FM), tensile strength (TS), and flexural strength (FS) of 100% PLA was improve by 14.9, 47.4, 6, and 32.9%, respectively. Whereas, the un‐notched impact strength of the nanocomposites suffer 2% deterioration. However, T g decreased by 0.3°C and T c increased by 10°C as 5 wt% n‐HA was added to 100% PLA. Afterwards, the 5% n‐HA/PLA composite were reinforced with 20 mol% continuous PGF and the TM, FM, TS, and FS of the tri‐layered composites were 162.6, 412.5, 28.4, and 157.4% higher as compared to 100%PLA. Furthermore, the storage modulus of the 1% n‐HA‐filled composites was 500 MPa lower than 100%PLA, while 5 wt% n‐HA‐filled composites showed similar storage modulus as 100% PLA. 5 wt% n‐HA‐filled composite showed the highest peak of loss modulus which may be attribute to the chain segment of PLA matrix after the incorporation of HA. Thus, n‐HA and PGF reinforcement resulted in improved mechanical properties of the composites and have great potential as biodegradable bone fixation device with enhanced load‐bearing ability.

Synergized high‐load bearing bone replacement composite from poly(lactic acid) reinforced with hydroxyapatite/glass fiber hybrid filler—Mechanical and dynamic mechanical properties

“…Notably, good dispersion and improved interfacial interaction are among the most significant requisite for high mechanical performance composites. In fact, poor interfacial adhesion has been reported to trigger increased void formation in reinforced polymer composites 21,31 . Therefore, the impact of these factors on the mechanical performance the resulting composites is discussed in the subsequent section.…”

“…The notable peaks are highlighted in the figure, which includes the OH stretching vibration at the higher wavelength above 3200 cm −1 , the vibrational stretching of symmetric and asymmetric CH bond around 2800 to 3050 cm −1. 28 The peak at 1750 cm −1 in the PLA spectra is known to represent carbonyl (CO) stretching peak, while the peaks at 1455 and 1378 cm −1 are characteristic CC symmetric stretching and CH symmetric deformation peaks, respectively 21,29 . The CO stretching peak from the ester and carboxylic acid groups of PLA can be seen at 1166 cm −1.…”

“…The CO stretching peak from the ester and carboxylic acid groups of PLA can be seen at 1166 cm −1. 29 In the modified HA, the bands around 3400 cm −1 and at 630 cm −1 are due to vibrational OH stretching, while the peaks around 960 cm −1 and around 560 to 650 cm −1 represents vibrational stretching and deformation of , respectively 21,30 . On the other hand, the SiOSi in GF is represented by the wide band around 900 to 1200 cm −1 .…”

“…These include fiber distribution, fiber content, fiber aspect ratio, and interfacial interactions within the composite 19,20 . Notwithstanding, GF holds great potential for fabrication of high‐load bearing structural biomaterials based on their very high mechanical properties 21 . In addition, the rate of ion release and degradation of these fibers can be easily tailored.…”

“…In addition, phosphate GFs have been reported to exhibit good bioactivity and osteoinduction properties 22 . Although there are various possible techniques for the processing of PLA based medical/orthopedic materials, 21–23 fabrication of medical/biomedical biomaterials via extrusion/injection molding offers great balance between cost, material properties, and technical feasibilities. In addition, this approach is devoid of organic chemicals and they are established industrial processing methods, which makes them suitable for mass production of materials various applications including orthopedic materials 24,25 .…”