Preparation of thermoplastic polyurethane/graphene oxide composite scaffolds by thermally induced phase separation

Abstract

In this study, biomedical thermoplastic polyurethane/ graphene oxide (TPU/GO) composite scaffolds were successfully prepared using the thermally induced phase separation (TIPS) technique. The microstructure, morphology, and thermal and mechanical properties of the scaffolds were characterized by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), and compression tests. Furthermore, NIH 3T3 fibroblast cell viability on the porous scaffolds was investigated via live/dead fluorescent staining and SEM observation. FTIR and Raman results verified the presence of GO in the composites. SEM images showed that the average pore diameter of the composite scaffolds decreased as the amount of GO increased. Additionally, the surface of the specimens became rougher due to the embedded GO. The compressive modulus of composite specimens was increased by nearly 200% and 300% with the addition of 5% and 10% GO, respectively, as compared with pristine TPU. 3T3 fibroblast culture results showed that GO had no apparent cytotoxicity. However, high loading levels of GO may delay cell proliferation on the specimens.

Lightweight conductive graphene/thermoplastic polyurethane foams with ultrahigh compressibility for piezoresistive sensing

“…However, the increase of graphene loading led to wider and shallower endothermic curves and the melting enthalpy of the conductive foam with 3 wt% loading dropped to only 3.383 J g À1 , which might be due to the fact that the addition of graphene inhibited the crystallization of the TPU hard segments, leading to the decrease in the crystalline size of TPU molecules. 28,[47][48][49] As for the influence of graphene on the T g of CPC foams, it can be seen that the T g decreases with increasing graphene content, Fig. 3(b).…”

“…23 Meanwhile, lightweight and high compressibility are of great importance for piezoresistive sensors to satisfy different practical demands. Due to the merits of lightweight, large specific surface area and high porosity, porous polymer foams have been widely used in many fields, including electromagnetic interference (EMI) shielding, [24][25][26][27] biological scaffolds [28][29][30][31] and super adsorbents. [32][33][34] As for the CPC based piezoresistive sensors, the introduction of a three-dimensional porous structure must be an effective strategy for achieving promising piezoresistive performance for widespread applications.…”

“…The interaction between the N-H bond of TPU and the remaining oxygenated groups of graphene accounts for the variation of FT-IR spectra. 28 …”

In vitrocytocompatibility of one-dimensional and two-dimensional nanostructure-reinforced biodegradable polymeric nanocomposites

“…14,30,31 The in vitro cytotoxicity of other carbon nanomaterials-reinforced PPF nanocomposites (MWCNTs, SWGONRs, MWGONRs, and GONPs) and inorganic nanomaterials-reinforced PPF nanocomposites (WSNTs and MSNPs) has not been reported. Cytocompatibility of some of these nanomaterials incorporated into other polymer nanocomposites such as PLGA (nonporous CNT/ PLGA 32 and porous GONP/PLGA 33 ), and PU (porous GONP/ PU scaffolds 34 ) has been investigated.…”

Graphene‐Oxide‐Decorated Microporous Polyetheretherketone with Superior Antibacterial Capability and In Vitro Osteogenesis for Orthopedic Implant

“…MG‐63 cells were seeded on the samples at an initial density of 1 × 10 5 to study the cytocompatibility and morphology, and then we observed the morphology of the cells by SEM after culturing for 1 and 5 d. Previous studies had reported that the addition of GO on the biopolymer matrix could enhance cell attachment and proliferation via a large number of hydrophilic groups on the surface . As depicted in Figure 9 , the majority of cells are spherical at the first day on bare PEEK; however, on the sulfonate PEEK group, lamellipodia can be observed clearly.…”