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The physical and mechanical properties of novel bio-based polymer blends of polylactic acid (PLA), poly(butylene succinate) (PBS), and poly (butylene adipate-co-terephthalate) (PBAT) with various added amounts of nanohydroxyapatite (nHA) were investigated in this study. The formulations of PLA/PBS/PBAT/nHA blends were divided into two series, A and B, containing 70 or 80 wt% PLA, respectively. Samples of four specimens per series were prepared using a twin-screw extruder, and different amounts of nHA were added to meet the regeneration needs of bone graft materials. FTIR and XRD analyses were employed to identify the presence of each polymer and nHA in the various blends. The crystallization behavior of these blends was examined using DSC. Tensile and impact strength tests were performed on all samples to screen feasible formulations of polymer blends for bone graft material applications. Surface morphology analyses were conducted using SEM, and the dispersion of nHA particles in the blends was further tested using TEM. The added nHA also served as a nucleating agent aimed at improving the crystallinity and mechanical properties of the blends. Through the above analyses, the physical and mechanical properties of the polymer blends are reported and the most promising bone graft material formulations are suggested. All blends were tested for thermal degradation analysis using TGA and thermal stability was confirmed. The water absorption experiments carried out in this study showed that the addition of nHA could improve the hydrophilicity of the blends. [ABSTRACT FROM AUTHOR]

Nonisocyanate polyurethane (NIPU) was synthesized using different concentrations of C36‐alkylenediamine (C36DDA), hexamethylene diamine, and a cyclic carbonate monomer synthesized from bisphenol A epoxy resin and carbon dioxide. The structures, molecular weights, thermal behaviors, and stabilities of the NIPU copolymers were evaluated using 1H nuclear magnetic resonance, Fourier transform infrared spectroscopy, gel permeation chromatography, thermogravimetric analysis, and differential scanning calorimetry measurements. All synthesized NIPUs were amorphous and exhibited good Td−5% thermal stabilities above 250°C; Tg decreased from 73 to 51°C as C36DDA content increased from 0% to 10% based on dynamic mechanical analysis tests. Furthermore, ethylenediamine (EDA) as a chain extender incorporating a small amount of crosslinker 1,2,4,5‐benzenetetracarboxylic acid (PMA) can enhance the melt strength of a partially three‐dimensional network, and the attained NIPU showed elastic properties. Thus, the NIPU synthesized with 7.5% and 10% C36DDA containing small amounts of EDA and PMA were suitable choices for supercritical CO2 foaming; their morphologies and mechanical behaviors were examined by scanning electron microscopy and DMA, and the densities of foamed NIPU with 7.5% and 10% C36DDA were calculated as 432 and 215 kg m−3 with pore sizes of 10–20 μm, respectively. The maximum stresses were attained at 149.5 and 123.4 kPa, and the foamed NIPU displayed rigid foam behaviors owing to the compression behaviors of the stress–strain curves. [ABSTRACT FROM AUTHOR]