In this study, vinyltrimethoxysilane-treated hydroxyapatite (vHAP) and PMMA-grafted HAP (gHAP) were successfully prepared from original HAP (oHAP). Three kinds of HAP (oHAP, vHAP and g HAP) were used as additives for the preparation of three groups of HAP-modified PMMA bone cements (oHAP-BC, vHAP-BC and gHAP-BC). The setting, bending and compression properties of the bone cements were conducted according to ISO 5833:2002. The obtained results showed that the maximum temperature while curing the HAP-modified bone cements (HAP-BCs) decreased from 64.9 to 60.8 °C and the setting time increased from 8.1 to 14.0 min, respectively, with increasing HAP loading from 0 to 15 wt.%. The vHAP-BC and gHAP-BC groups exhibited higher mechanical properties than the required values in ISO 5833. Electron microscopy images showed that the vHAP and gHAP nanoparticles were dispersed better in the polymerized PMMA matrix than the oHAP nanoparticles. FTIR analysis indicated the polar interaction between the PO4 groups of the HAP nanoparticles and the ester groups of the polymerized PMMA matrix. Thermal gravimetric analysis indicated that mixtures of ZrO2/HAPs were not able to significantly improve the thermal stability of the HAP-BCs. DSC diagrams showed that the incorporation of gHAP to PMMA bone cement with loadings lower than 10 wt.% can increase Tg by about 2.4 °C.
Electrolyte films based on poly(methyl methacrylate) (PMMA), poly(vinyl chloride) (PVC) were prepared by using casting method with the addition 100 wt.% to 240 wt.% of dioctyl phthalate (DOP), propylene carbonate (PC) as plasticizers and Mg(ClO4)2 as an electrolytic salt. The Fourier infrared spectra (FTIR), tensile, electrical properties, surface morphology of electrolyte films were investigated. The FTIR spectra of plasticized PMMA/PVC blends indicated that there were secondary interactions between plasticizers and PMMA/PVC matrix. There were also molecular interactions between Mg(ClO4)2 and the blends, which indicated that Mg(ClO4)2 was well dissolved and solvated in the blends. Tensile results showed that Mg(ClO4)2 improved the elongation at break and the reduced tensile strength and Young’s modulus of the blends due to this salt can act as an internal lubricant for the blends. The SEM and EDX-mapping micrographs showed the wrinkled surface morphology of the electrolyte film, all raw materials were dispersed regularly into each others at molecular and ionic levels. For the electrolytes containing 10 wt.% of Mg(ClO4)2, the ionic conductivity increased with increasing plasticizer content and achieved in the range of 1.80 × 10-4 - 1.03 × 10-3 (S/cm). For the electrolyte containing 200 wt.% of the plasticizer, the ionic conductivity increased with increasing magnesium salt content and achieved in the range of 2.31 × 10-4 - 4.57 × 10-3 (S/cm).
<p class="NidungTmtt-Abstract"><strong>Abstract</strong>: According to Conference of the Parties 22 (COP22) statement, climate change adaptation is the concern of not only an individual but also the whole society. Since the climate change issue is a multidimensional problem, decision-making in climate change adaptation is a complex process. In this paper, we analyze the advantages and disadvantages of three main group of decision-support tools, namely Expert preference, Monetary valuation, and Multi-criteria analysis (MCA). The paper recommends MCA in general and AHP in particular as effective tools to compensate for the disadvantages of other techniques as well as to overcome the challenges and requirements from the climate change adaptation decision-making process.</p><p><strong>Keywords</strong>: climate change, AHP, MCA, monetary valuation, expert preference</p>
In this study, new types of gel polymer blend electrolytes (GPBEs) were prepared with the synthesized PVC-g-PMMA graft copolymer, PMMA, plasticizers (propylene carbonate (PC), dioctyl phthalate (DOP)), and different loadings of Mg(ClO4)2 via the solution casting method using tetrahydrofuran as solvent. Fourier transform infrared (FTIR) spectra of the electrolytes showed mutual molecular interactions between Mg(ClO4)2 and organic moieties. The scanning electron microscopy images of the GPBEs showed their wrinkled surface morphology due to their low elastic modulus and high flexibility. Energy-dispersive X-ray (EDX) spectroscopy and mapping technique revealed the regular distributions of all atomic elements such as Cl, Mg, O, and C in the doped GPBEs. With increasing the Mg salt concentration, Young’s modulus and tensile strength of the GPBEs strongly decreased. Interestingly, the elongation at break of the GPBEs was higher than that of neat (undoped) GPBE and achieved the highest value of 215% at the salt content of 20 wt.%. The AC conductivity and ionic conductivity, as well as dielectric permittivity of plasticized PMMA/PVC-g-PMMA/Mg(ClO4)2 GPBE,s increased with frequency and Mg(ClO4)2 doping content. Ionic conductivity of the doped GPBEs can be achieved from
5.51
×
10
−
5
to
4.42
×
10
−
4
(S.cm-1) using Mg(ClO4)2 contents in the range from 10 to 40 wt.%. The doped GPBEs are thermally stable up to 100°C with very low weight losses. The GPBE doped with 20 wt.% of Mg(ClO4)2 can be used as a new type of electrolyte for developing Mg batteries.
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