“…Similar results were presented by samples E-A/ ZrP (0.5:1 and 1:1). Only thermal curve of E-A/ZrP (2:1) sample showed an endothermic peak around 100°C which was attributed to the adsorbed water similarly to reported by Mendes et al 23 .…”
“…The first around 100-200°C, the second at 400-500°C and third in the vicinity of 500-600°C were associated to the releasing of adsorbed water, α-ZrP dehydroxylation and chemical transformation from phosphate to pyrophosphate, respectively 23 . The amine initiated its degradation at 225°C and T max occurred at 299°C.…”
In order to search nanofiller for controlling release of drugs lamellar α-zirconium phosphate (α-ZrP) was modified with ether-amine oligomer (E-A). Synthesis and chemical modification followed specific reaction conditions and different EA:ZrP ratios. Infrared spectra showed strong interaction between P-OH and NH 2 groups. Thermogravimetric curves showed that ether-amine oligomer was incorporated by ZrP. Interlamellar space of α-ZrP increased at least four times indicating intercalation. The relaxometry analysis indicated that α-ZrP molecular mobility changed according to the etheramine amount. The scanning electron microscopy/energy dispersive analysis revealed the presence of octadecylamine inside the α-ZrP galleries. The results showed that P-OH group (Brønsted acid) and amine group (Brønsted base) reacted to each other, resulting in an ionic bond PO-+ 3 HN-[-(CH 2-CH 2-O) m-(CH 2-C-H(CH 3)-O) n-]. Partially intercalated nanofiller were achieved.
“…Similar results were presented by samples E-A/ ZrP (0.5:1 and 1:1). Only thermal curve of E-A/ZrP (2:1) sample showed an endothermic peak around 100°C which was attributed to the adsorbed water similarly to reported by Mendes et al 23 .…”
“…The first around 100-200°C, the second at 400-500°C and third in the vicinity of 500-600°C were associated to the releasing of adsorbed water, α-ZrP dehydroxylation and chemical transformation from phosphate to pyrophosphate, respectively 23 . The amine initiated its degradation at 225°C and T max occurred at 299°C.…”
In order to search nanofiller for controlling release of drugs lamellar α-zirconium phosphate (α-ZrP) was modified with ether-amine oligomer (E-A). Synthesis and chemical modification followed specific reaction conditions and different EA:ZrP ratios. Infrared spectra showed strong interaction between P-OH and NH 2 groups. Thermogravimetric curves showed that ether-amine oligomer was incorporated by ZrP. Interlamellar space of α-ZrP increased at least four times indicating intercalation. The relaxometry analysis indicated that α-ZrP molecular mobility changed according to the etheramine amount. The scanning electron microscopy/energy dispersive analysis revealed the presence of octadecylamine inside the α-ZrP galleries. The results showed that P-OH group (Brønsted acid) and amine group (Brønsted base) reacted to each other, resulting in an ionic bond PO-+ 3 HN-[-(CH 2-CH 2-O) m-(CH 2-C-H(CH 3)-O) n-]. Partially intercalated nanofiller were achieved.
“…PP spectrum shows multiple bands around 3000–2800 cm −1 (stretching of C-H bond in CH 3 , CH 2 and CH groups), 1500–1400 cm −1 (respectively, asymmetric bending and bending of C–H bond in CH 3 and CH2 groups), 1400–1300 cm −1 (symmetric bending of C–H bond in CH 3 group) and 1300–800 cm −1 (bending of C–H bond in CH 3 group). 18,24 Figure 2.FT-IR spectrum of nano-ZrPOct; neat PP, processed at 90 r/min; PP/nano-ZrPOct, processed at 30 r/min; PP/nano-ZrPOct, processed at 60 r/min; PP/nano-ZrPOct, processed at 90 r/min.…”
Section: Resultsmentioning
confidence: 99%
“…Experimental intercalation of zirconium phosphate with octadecylamine followed procedures described previously. 18 Amine:ZrP molar ratio of 2:1 was investigated. Ethanol/water 2:1 solution of zirconium phosphate and amine was mixed and remained in contact during 24 h, in a 40℃ system.…”
Nanocomposite based on polypropylene and octadecylamine-modified lamellar-zirconium phosphate (PP/nano-ZrPOct) was prepared by melt processing. The action of the nanofiller and screw speed on the properties were evaluated. SEM images revealed that at highest screw speed, the higher nano-ZrPOct dispersion was achieved. In WAXD diffractrograms, some nanofiller diffraction peaks disappeared and a new peak was observed at low angle. There was evidence of increase of thermal stability although only discrete increasing in initial degradation temperature has been noticed. Melting and crystallization temperatures were invariable but crystallinity degree was influenced with a decreasing behavior at highest screw speed. The results strongly evidenced that the intercalation of the PP chains inside the nano-ZrPOct galleries and some degree of delamination of the nanofiller platelets have been achieved.
“…The molecular dynamical behavior of the PVP and its nanomaterials were evaluated by NMR relaxometry, through the proton spin-lattice relaxation time, which is a parameter sensitive the small changes in the intermolecular interaction and nanoparticle dispersion [6], [18], [19]. Firstly, the commercial PVP was analyzed and relaxation behavior was used to compare with the samples after ZnO incorporation, to observe the changes in the molecular dynamics, due to intermolecular interaction and ZnO dispersion, since the nanoparticles has good dispersion and distribution in the PVP matrix.…”
Section: Figure 1: Ftir Of Pvp Pvp Film and Znomentioning
Hydrophilic polymer matrix systems (HPMSs) are a highly relevant tool for drugs delivery whose bioavailability is impaired by low hydrosolubility. Besides this, when associated with nanoparticles these systems can provide better control over release profile of the active drug, maintaining the posology. Since polyvinylpyrrolidone (PVP) and zinc oxide (ZnO) are safe materials for use in the human body, we studied the effects of ZnO nanoparticle ratios on the characteristics of PVP matrix. For that purpose, nanocomposites were prepared by solution casting method and characterized by X-ray Fluorescence (XRF), Fourier Transform Infrared (FTIR), Thermal Gravimetric Analyses (TGA), Differential Scanning Calorimetry (DSC), X-ray Diffraction (XDR) and Low-field Nuclear Magnetic Resonance (LF-NMR) technique, using relaxometry. We also analyzed the effects of the system on two broad-spectrum antimicrobial drugs. The characterization results of the new materials indicate good interaction of the nanoparticles with the polymer, and this fact suggests that these new materials may have a retarding effect on drug release. The results also showed no disruptive interaction of the matrix system important to the action of the antimicrobials.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
