J Biomed Mater Res B Appl Biomater
October 2019
The creep and recovery and the stress relaxation behaviors of poly(butylene adipate-co-terephthalate) (PBAT) and polyhydroxyalkanoates (PHA) binary blends incorporating 30 wt % of a mixture of trisilanolisobutyl polyhedral oligomeric silsesquioxanes (POSS) and calcium phosphate glass (CaP-g) were investigated under simulated physiological and human body temperature conditions. The synergistic effect of PHA and CaP-g/POSS filler remarkably improved the creep behavior of the PBAT matrix and decreased its residual strain, consequently enhancing its elastic recovery. A considerable increase of the relaxation modulus of the hybrid materials was also observed upon incorporation of PHA and CaP-g/POSS.
View Article and Find Full Text PDFPoly(butylene adipate-co-terephthalate) (PBAT) was first chemically modified via free radical grafting with maleic anhydride (MA) and the MA-g-PBAT graft copolymer was then used as a matrix material to obtain cellulose nanocrystal (CNC)-reinforced MA-g-PBAT bionanocomposites via reactive extrusion process to accelerate efforts to develop functional bioabsorbable polymer nanocomposites with improved properties. The molecular structure of the PBAT after chemical modification with maleic anhydride was confirmed by H NMR and FTIR spectroscopy. The morphological observation of the nanocomposites revealed that the CNCs were finely dispersed in the matrix.
View Article and Find Full Text PDFThe physical modification of glass transition temperature (T(g)) and properties of materials via blending is a common practice in industry and academia and has a large economic advantage. In this context, simple production of hitherto unattainable new inorganic glass blends from already existing glass compositions via blending raises much hope with the potential to provide new glasses with new and improved properties, that cannot be achieved with classical glass synthesis, for a plethora of applications such as computers screens, glass-to-metal seals, and storage materials for nuclear wastes. Here, we demonstrate that blends of the specific glass compositions studied are miscible in all proportions, an unreported phenomenon in hard condensed matter like glass.
View Article and Find Full Text PDFIncorporation of polyhedral oligomeric silsesquioxanes (POSS) into poly(ester urethanes) (PEU) as a building block results in a PEU/POSS hybrid polymer with increased mechanical strength and thermostability. An attractive feature of the new polymer is that it forms a porous matrix when cast in the form of a thin film, making it potentially useful in tissue engineering. In this study, we present detailed microscopic analysis of the PEU/POSS matrix and demonstrate its biocompatibility with cell culture.
View Article and Find Full Text PDFThis study was aimed at enhancing the physical stability of the drug clotrimazole (CT) and the polymer contained within hot-melt extrusion (HME) films using polymer blends of hydroxypropyl cellulose (HPC) and poly(ethylene oxide) (PEO). The HME films were investigated for solid-state characteristics, moisture sorption, bioadhesivity, mechanical properties, glass transition temperature, release characteristics, and physical and chemical stability of the drug and the polymer within the HME films. The solid-state characterization of the drug and the polymer was performed using differential scanning calorimetry, x-ray diffractometry, and dynamic mechanical analysis.
View Article and Find Full Text PDFThe interfacial tension of hybrids composed of a tin-based phosphate glass (Pglass) and thermoplastic polymers, low-density polyethylene (LDPE), polystyrene (PS), and polypropylene (PP) was investigated using pendant drop and droplet deformation methods. High surface tension values were determined for the pure Pglass and subsequently used to obtain interfacial tension values that were found to be greater than that of most polymer blends reported in the literature. Small amplitude oscillatory shear data were fitted to the Choi-Schowalter and Palierne emulsion models in order to estimate the interfacial tension and to validate the accuracy (or lack thereof) of using a polymer emulsion model on the special Pglass-polymer systems.
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