Characterization Of Poly Research Articles

Preparation and characterization of poly(3-hydroxybutyrate-co-4-hydroxybutyrate)/gelatin composite nanofibrous

In order to compound gelatin (GEL) with poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P(3,4HB)) to improve the hydrophilicity and biocompatibility, a simple and convenient method for preparing P(3,4HB)/GEL composite nanofibrous (P/G-CNF) was proposed. Alkyl Polyglycoside (APG) was used as an emulsifier to prepare a stable P(3,4HB)/GEL composite solution, and novel P/G-CNF was prepared by electrospinning. The intermolecular interaction, micromorphology and porosity, crystallization and mechanical properties, hydrophilicity and cytocompatibility of P/G-CNF were characterized. The results reveal that P(3,4HB), APG and GEL form many hydrogen bonds. When the m(P(3,4HB):GEL) is 10:2, the as-prepared nanofibrous exhibit the best micromorphology with a diameter and porosity of 604 nm and 68.33%. With the increasing GEL content, the crystallization and mechanical properties of P(3,4HB)/GEL composite nanofibrous scaffold (P/G-CNS) are further enhanced and decline after reaching the maximum. The hydrophilicity of P/G-CNS is significantly improved by introducing GEL. The cell proliferation rate of P/G-CNS is higher than 100%, of which the cytotoxicity grade is 0, indicating that it is non-cytotoxic. The P/G-CNS has excellent cytocompatibility and provides better cell attachment, growth and proliferation, showing promising application prospects for tissue regeneration and biomedical materials.

Synthesis and characterization of poly (aniline-co-p-nitroaniline) (PANA) and its corrosion-resistant properties against corrosive media

The co-polymerization of aniline with p-nitroaniline has been synthesized in oxalic acid medium, here ammonium persulfate (APS) acts as an oxidant. TGA analysis was used to study the thermal stability of the copolymer, as well as FTIR, UV–Vis spectroscopy, and XRD. The synthetic poly (aniline-co-p-nitroaniline) (PANA) is used as a barrier/redox pigment for PANA coatings. The anti-corrosion study on PANA coatings was performed with a 3% NaCl solution for up to 35 days. The coating resistance of PANA coatings is three orders of magnitude more than that of pure epoxy coatings, according to the results of electrochemical impedance spectroscopy (EIS). The scanning vibrating electrode method (SVET) was used to investigate the self-healing characteristics of this PANA coating.

Synthesis and characterization of poly(hexamethylene 2,6-naphthalate)-block-poly(tetrahydrofuran) copolymers with shape memory effect

Shape memory polymers (SMPs) are able to return to their previous shape after deformation under certain conditions. Several block copolymers can exhibit shape memory behavior. The blocks in copolymers are usually immiscible, which leads to phase separation into rigid and flexible segments. For that reason, these materials combine the mechanical properties of elastomers with the processing properties of thermoplastic. Thus, a poly(hexamethylene 2,6-naphthalate) (PHN) and a series of poly(hexamethylene 2,6-naphthalate)-block-poly(tetrahydrofuran) (PHN-b-N-pTHF) copolymers were synthesized via melt polycondensation. The content of the N-pTHF flexible segment varied from 15 to 50 wt.%. The materials were characterized with the use of Fourier transformed infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), X-ray diffraction (XRD) analysis, the tensile tests (static and cyclic), and the cyclic thermo-mechanical analysis. The PHN-b-N-pTHF 50/50 was proved to be a promising thermoplastic shape memory polymer (SMP).

Synthesis and Characterization of poly (N-glycidyl-2-oxazolidone) Using a Green and Efficient Catalyst

Synthesis and Characterization of poly (N-glycidyl-2-oxazolidone) Using a Green and Efficient Catalyst

Fabrication and Characterization of Poly(vinyl alcohol)-chitosan-capped Silver Nanoparticle Hybrid Membranes for Pervaporation Dehydration of Ethanol.

Chitosan-capped silver nanoparticle (CS-capped AgNPs)-incorporated Poly(vinyl alcohol) (PVA) hybrid membranes were prepared by a solution-casting technique for ethanol dehydration via pervaporation. The incorporation of CS-capped AgNPs into the PVA membrane and its influence on membrane properties and pervaporation-separation process of azeotropic water/ethanol mixture was studied. The addition of CS-capped AgNPs into the PVA membrane reduced the crystallinity, thereby increasing the hydrophilicity and swelling degree of the hybrid membrane, supported by contact angle (CA) analyzer and swelling degree experiments, respectively. Fourier transform infrared spectroscopy (FTIR) demonstrated the formation of polymeric matrix between PVA and CS and also the binding of AgNPs onto the functional group of CS and PVA, which was also reflected in the microstructure images demonstrated by scanning electron microscopy (SEM) and by 2θ angle of wide-angle X-ray diffraction (WAXD). The effect of CS-capped AgNPs on the thermal stability of the hybrid membrane was demonstrated by differential scanning calorimetry (DSC) and thermogravimetric analyzer (TGA). These characteristics of the hybrid membrane positively impact the efficiency of the dehydration of ethanol, as indicated by pervaporation experiments. The best performances in total flux (12.40 ± 0.20 × 10−2 kg/m2 h) and selectivity (3612.33 ± 6.03) at 30 °C were shown for CS-capped AgNPs PVA hybrid membrane containing 2 wt.% CS-capped AgNPs (M-4). This confirms that the developed hybrid membranes can be efficiently used to separate water from azeotropic aqueous ethanol.

Preparation and Characterization of Poly(lactide-co-glycolide-co-ε-caprolactone)- 1,4-Butanediamine-Modified Poly(lactide-co-glycolide)/Nano-Biaoactive Glass-β-Tricalcium Phosphate Composite Scaffolds

Polymer/bioceramic composite scaffolds have gained importance in treating bone defects. In this paper we described a novel degradable scaffold material for bone tissue repairing prepared by combining poly(lactide-co-glycolide-co-ε-caprolactone) (PLLGC) and 1,4-butanediamine-modified poly(lactide-co-glycolide) (BMPLGA) with nano-biaoactive glass (NBAG) and nano β-tricalcium phosphate (β-TCP). The composite scaffolds were characterized by using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. The FTIR results indicated that the inorganic fillers of NBAG and β-TCP were successfully incorporated into the PLLGC/BMPLGA matrix. The influences of the inorganic filler content and freezing temperature on the porosity and compressive strength of the composite scaffolds were studied. The composite scaffolds showed an interconnected pore structure with the pore size ranging from 20 to 100 μm depending on the freezing temperature and the inorganic fillers. The compressive strength was enhanced with increasing content of the inorganic fillers and the freezing temperature; however, the porosity decreased. We suggest the PLLGC-BMPLGA/NBAG-β-TCP composite scaffolds have great potential for application in bone tissue regeneration.

Microfluidic Synthesis of Microgel Building Blocks for Microporous Annealed Particle Scaffold

The microporous annealed particle (MAP) scaffold platform is a subclass of granular hydrogels. It is composed of an injectable slurry of microgels that can form a structurally stable scaffold with cell-scale porosity in situ following a secondary light-based chemical crosslinking step (i.e., annealing). MAP scaffold has shown success in a variety of regenerative medicine applications, including dermal wound healing, vocal fold augmentation, and stem cell delivery. This paper describes the methods for synthesis and characterization of poly(ethylene glycol) (PEG) microgels as the building blocks to form a MAP scaffold. These methods include the synthesis of a custom annealing macromer (MethMAL), determination of microgel precursor gelation kinetics, microfluidic device fabrication, microfluidic generation of microgels, microgel purification, and basic scaffold characterization, including microgel sizing and scaffold annealing. Specifically, the high-throughput microfluidic methods described herein can produce large volumes of microgels that can be used to generate MAP scaffolds for any desired application, especially in the field of regenerative medicine.

Microfluidic Synthesis of Microgel Building Blocks for Microporous Annealed Particle Scaffold.

The microporous annealed particle (MAP) scaffold platform is a subclass of granular hydrogels. It is composed of an injectable slurry of microgels that can form a structurally stable scaffold with cell-scale porosity in situ following a secondary light-based chemical crosslinking step (i.e.,annealing). MAP scaffold has shown success in a variety of regenerative medicine applications, including dermal wound healing, vocal fold augmentation, and stem cell delivery. This paper describes the methods for synthesis and characterization of poly(ethylene glycol) (PEG) microgels as the building blocks to form a MAP scaffold. These methods include the synthesis of a custom annealing macromer (MethMAL), determination of microgel precursor gelation kinetics, microfluidic device fabrication, microfluidic generation of microgels, microgel purification, and basic scaffold characterization, including microgel sizing and scaffold annealing. Specifically, the high-throughput microfluidic methods described herein can produce large volumes of microgels that can be used to generate MAP scaffolds for any desired application, especially in the field of regenerative medicine.

Controllable Polymerization of N -Substituted β-Alanine N -Thiocarboxyanhydrides for Convenient Synthesis of Functional Poly(β-peptoid)s

Controllable Polymerization of <i>N</i> -Substituted β-Alanine <i>N</i> -Thiocarboxyanhydrides for Convenient Synthesis of Functional Poly(β-peptoid)s

Preparation and Characterization of Poly(AMPS-co-Aa-co-DEAA)/MMT Nanocomposite Hydrogels

Nanocomposite (NC) hydrogels poly (AMPS-co-AA-co-DEAA)/MMT were prepared by in situ free radical polymerization by using montmorillonite (MMT) as the inorganic cross-linking agent and 2-acrylamido-2-methylpropanesulfonic acid (AMPS), acrylic acid (AA) and N,N-diethylacrylamide (DEAA) as the monomers. Based on the confirmation of the composition and network structure of the nanocomposite hydrogels, the mechanical properties and the swelling behavior in buffers and salt solutions with different pH levels were systematically investigated. The hydrogel had good mechanical properties due to the homogeneous dispersion of MMT. Its tensile strength at break reached 0.1 MPa, and elongation at break reached 1807%. The nanocomposite hydrogel exhibited certain pH and salt-sensitive behavior. As for the structure of the synthetic hydrogel, its morphology was determined by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM).

PH-responsive phototherapeutic poly(acrylic acid)-calcium phosphate passivated TiO2 nanoparticle-based drug delivery system for cancer treatment applications

This paper reports the hydrothermal synthesis and characterization of poly(acrylic acid)-calcium phosphate passivated TiO2 nanoparticles (TiO2@PAA-CaP NPs). The efficient loading and release of doxorubicin (DOX) from the TiO2@PAA-CaP NPs was observed at pH = 7.4 and 5.2, respectively. The loading and encapsulation amount of DOX in TiO2@PAA-CaP NPs was approximately fifteen and eight times as large as that of unfunctionalized TiO2 NPs, respectively, suggesting the PAA-CaP passivation layer enhanced the interaction between DOX and TiO2@PAA-CaP NPs. The DOX-loaded TiO2@PAA-CaP (TiO2@PAA-CaP(DOX)) NPs exhibited much faster cumulative DOX release at acidic pH = 5.2 than at neutral pH = 7.4 because of the pH-responsive dissolution properties of the PAA-CaP passivation layer. TiO2@PAA-CaP(DOX) NPs showed higher cytotoxicity towards MCF-7 tumor cells than free DOX. Confocal fluorescence microscopy and flow cytometry confirmed the enhanced cellular uptake of TiO2@PAA-CaP(DOX) NPs followed by the intracellular release of DOX. Overall, TiO2@PAA-CaP(DOX) NPs demonstrated significantly higher total cytotoxicity towards MCF-7 tumor cells under UV-A irradiation, which was attributed to a synergistic effect between efficient DOX delivery and enhanced photoinduced reactive oxygen species (ROS) generation. This study provides a facile means of synthesizing TiO2-based multifunctional nanocarriers with pH-responsive drug delivery and ROS generation essential for high efficacy therapeutic applications in cancer treatments.

Phosphorylation‐assisted synthesis and characterization of poly(3,4'‐oxydiphenylene furanamide) as a wholly aromatic polyamide using biomass‐derived 2,5‐furandicarboxylic acid

AbstractWe report the phosphorylation‐assisted polymerization and characterization of 2,5‐furandicarboxylic acid (FDCA)‐based wholly aromatic polyamide. For this purpose, poly(3,4′‐oxydiphenylene furanamide) (PODFA) was synthesized via solution polymerization of FDCA with 3,4′‐oxydiphenylamine (ODPA) in the presence of triphenyl phosphite and pyridine. The spectroscopic analyses and solution viscosity measurement revealed the successful synthesis of a relatively high molecular weight PODFA with good solubility in a variety of polar aprotic solvents without inorganic salts. PODFA could be thus processed into purely amorphous films with high flexibility in bending and folding deformation. The 39 μm thick PODFA film exhibited optical transparency, and the 65–100 μm thick films showed a transparent yellow or light brown color. The amorphous PODFA films were characterized to have excellent thermal and static mechanical properties in terms of a glass transition temperature of ~260°C, a thermal decomposition peak temperature of ~450°C, a residue of ~50% at 800°C under nitrogen gas condition, an initial modulus of 12.98 ± 1.84 GPa, a tensile strength of 84.6 ± 17.3 MPa, and a strain at break of 2.3 ± 1.5% at room temperature.

Preparation and characterization of poly(lactic acid)/boron oxide nanocomposites: Thermal, mechanical, crystallization, and flammability properties

AbstractIn this study, poly(lactic acid)/boron oxide nanocomposites (PLA/BONPs) were prepared by solution casting method and characterized by thermogravimetric analysis, differential scanning calorimetry analysis, limiting oxygen index (LOI) and mechanical test. The particle size of boron oxide was reduced to nanosize using SPEX ball mill and boron oxide nanoparticles (BONPs) were functionalized with oleic acid, [3‐(trimethoxylsilyl) propylmethacrylate] and triethoxyvinylsilane (VS). Obtaining of nanosized and surface functionalized BONPs enhanced the crystallinity, mechanical, and flammability properties of PLA/BONPs. Compared with the neat PLA, crystallinity increased from 13.68% to 32.55% for 5 wt% VS functionalized BONPs added nanocomposite, tensile strength increased from 41.25 ± 0.80 MPa to 51.12 ± 2.54 MPa for 2.5 wt% VS functionalized BONPs added nanocomposite and LOI increased from 21.2 to 26.8 for 5 wt% VS functionalized BONPs added nanocomposite. Functionalized BONPs increased the thermal degradation temperature of nanocomposite slightly. With the enhanced mechanical and flammability properties PLA/BONPs nanocomposites are good candidate for packaging, electronic, and automotives industries.

Hydrogen liberation from ethylenediamine bisborane hydrolysis by platinum nanoparticles

The synthesis and characterization of poly (N-vinyl-2-pyrrolidone)-protected platinum (Pt/PVP) nanoparticles with their employment as highly effective catalysts to liberate hydrogen from hydrolysis of ethylenediamine bisborane (EDAB) is reported here. The nanoparticles are easily synthesized from the reduction of platinum cations in ethanol/water mixture under refluxing. They remain stable for months without any sign of precipitation. They are characterized by fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction spectroscopy (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Pt/PVP nanoparticles provide the greatest TOF value (166.7 min−1) reported so far for the hydrolysis of EDAB. Their activation energy is 81.9 kJ mol-1 in the same reaction.

Thermally Stable Copolymers with Pendant “N-Arylimide” Groups Via Reversible Deactivation Radical Polymerization Technique

This paper reports the synthesis of copolymers of N-arylitaconimides (NAI) and methyl methacrylate (MMA) with random architecture via activator generated electron transfer atom transfer radical polymerization (AGET-ATRP) method, resulting in N-arylimide as pendant group.The AGET-ATRP is a versatile and famous reversible deactivation radical polymerization technique used to synthesize the well defined polymers. The structural characterizations of obtained copolymers were done using FT-IR, 1H-NMR spectroscopy and elemental analysis. The molecular weights of copolymers were in the range 8,000-20,000 g/ mol with a narrow polydispersity index i.e. 1.2-1.3. Thermal characterization of Poly(NAI-ran-MMA) copolymers were done using differential scanning calorimetry (DSC) and thermogravimetric analysis (TG/ DTG). DSC scans show 60-117% enhancements in the glass transition temperature (Tg), as compared to Poly(methyl methacrylate). The rate of copolymerization, molecular weight and Tg were observed to increase with increase in electron releasing nature of the substituent on aromatic ring of the pendant group.

Synthesis and characterization of poly (styrene-co-acrylamide)-graft-polyanilines as new sorbents for mercuric present in aqueous hydrocarbon liquids

BackgroundThe unprocessing hydrocarbon oil often contains high concentrations of mercury, which damages the metallic processing components and have health risk on workers and environment. Mercuric removal unit associated with natural gas processing plant is failed to complete mercury removal and then mercury distributed in most places of removal unit. Most of unremoved mercury are found in polar solutions.ResultsStyrene-co-acrylamide-graft-polyanilines were synthesized and characterized. The copolymer formed by free radical emulsion copolymerization of styrene-acrylamide (14:1) using ammonium persulphate (APS) at 60 °C. In addition, the grafting process was also achieved by oxidation chemical polymerization of the above copolymer with both aniline and 2-chloroaniline using APS. The synthetic polymeric samples were characterized using infrared (IR), x-ray diffraction (XRD), scan electron microscope (SEM), transition electron microscope (TEM), thermogravimetric analysis (TGA) and Brunauer–Emmett–Teller (BET) to confirm the polymerization process and investigate the polymeric samples as new sorbents for Hg (II). Both adsorption kinetics and isotherm models were checked.ConclusionsIn most cases Hg (II) was adsorbed as multi-layer on the obtained mesopores materials. The grafting process enhances the copolymer activity towards Hg (II) removal. The complete removal of mercury from water solution portion of mercuric removal unit was achieved by introduction of synthetic polymeric mesopores material based on styrene-co-acrylamide-graft-polyanilines. The removal efficiency closed to 100% in case of grafting with poly (2-chloroaniline).

Synthesis and Characterization of Poly (β-amino Ester) and Applied PEGylated and Non-PEGylated Poly (β-amino ester)/Plasmid DNA Nanoparticles for Efficient Gene Delivery.

Polymer-based nanocarriers require extensive knowledge of their chemistries to learn functionalization strategies and understand the nature of interactions that they establish with biological entities. In this research, the poly (β-amino ester) (PβAE-447) was synthesized and characterized, aimed to identify the influence of some key parameters in the formulation process. Initially; PβAE-447 was characterized for aqueous solubility, swelling capacity, proton buffering ability, and cytotoxicity study before nanoparticles formulation. Interestingly, the polymer-supported higher cell viability than the Polyethylenimine (PEI) at 100 μg/ml. PβAE-447 complexed with GFP encoded plasmid DNA (pGFP) generated nanocarriers of 184 nm hydrodynamic radius (+7.42 mV Zeta potential) for cell transfection. Transfection assays performed with PEGylated and lyophilized PβAE-447/pDNA complexes on HEK-293, BEAS-2B, and A549 cell lines showed better transfection than PEI. The outcomes toward A549 cells (above 66%) showed the highest transfection efficiency compared to the other cell lines. Altogether, these results suggested that characterizing physicochemical properties pave the way to design a new generation of PβAE-447 for gene delivery.

Fabrication and Characterisation of Poly(vinyl alcohol)/Deacetylated Crab-Shell Particles Biocomposites with Excellent Thermomechanical and Antibacterial Properties as Active Food Packaging Material

Fabrication and Characterisation of Poly(vinyl alcohol)/Deacetylated Crab-Shell Particles Biocomposites with Excellent Thermomechanical and Antibacterial Properties as Active Food Packaging Material

Formulation and Characterization of Poly (Ethylene Glycol)-Coated Core-Shell Methionine Magnetic Nanoparticles as a Carrier for Naproxen Delivery: Growth Inhibition of Cancer Cells.

Simple SummaryNaproxen was loaded onto a magnetic nanoparticle coated with polyethylene glycol. Magnetic nanoparticles (MNPs) were used in this study to develop a smart naproxen delivery system. One of the most potent COX-1 and COX-2 inhibitors is naproxen, which belongs to the NSAID family of drugs. Although this drug has a short half-life, it has considerable toxicities and side effects on gastrointestinal tissues. The significant potential of our proposed nanocarrier for biomedical applications has been widely recognized; we modified MNPs to attach to this drug via disulfide bonds, promote the selective release of naproxen in inflammatory cells, and prevent adverse effects on the digestive system. It was found that the cytotoxicity of the drug was lowered by this change, which prevented unspecific protein binding.An efficient and selective drug delivery vehicle for cancer cells can remarkably improve therapeutic approaches. In this study, we focused on the synthesis and characterization of magnetic Ni1−xCoxFe2O4 nanoparticles (NPs) coated with two layers of methionine and polyethylene glycol to increase the loading capacity and lower toxicity to serve as an efficient drug carrier. Ni1−xCoxFe2O4@Methionine@PEG NPs were synthesized by a reflux method then characterized by FTIR, XRD, FESEM, TEM, and VSM. Naproxen was used as a model drug and its loading and release in the vehicles were evaluated. The results for loading efficiency showed 1 mg of Ni1−xCoxFe2O4@Methionine@PEG NPs could load 0.51 mg of the naproxen. Interestingly, Ni1−xCoxFe2O4@Methionine@PEG showed a gradual release of the drug, achieving a time-release up to 5 days, and demonstrated that a pH 5 release of the drug was about 20% higher than Ni1−xCoxFe2O4@Methionine NPs, which could enhance the intracellular drug release following endocytosis. At pH 7.4, the release of the drug was slower than Ni1−xCoxFe2O4@Methionine NPs; demonstrating the potential to minimize the adverse effects of anticancer drugs on normal tissues. Moreover, naproxen loaded onto the Ni1−xCoxFe2O4@Methionine@PEG NPs for breast cancer cell lines MDA-MB-231 and MCF-7 showed more significant cell death than the free drug, which was measured by an MTT assay. When comparing both cancer cells, we demonstrated that naproxen loaded onto the Ni1−xCoxFe2O4@Methionine@PEG NPs exhibited greater cell death effects on the MCF-7 cells compared with the MDA-MB-231 cells. The results of the hemolysis test also showed good hemocompatibility. The results indicated that the prepared magnetic nanocarrier could be suitable for controlled anticancer drug delivery.

Synthesis and Characterization of Poly(5'-hexyloxy-1',4-biphenyl)-b-poly(2',4'-bispropoxysulfonate-1',4-biphenyl) with High Ion Exchange Capacity for Proton Exchange Membrane Fuel Cell Applications.

Proton exchange membrane (PEM) is pivotal for proton exchange membrane fuel cells (PEMFCs). In the present work, a block copolymer with hydrophilic alkyl sulfonated side groups and hydrophobic flexible alkyl ether side groups, poly(5'-hexyloxy-1',4-biphenyl)-b-poly(2',4'-bispropoxysulfonate-1',4-biphenyl) (HBP-b-xBPSBP), is designed and synthesized by copolymerization of the hydrophilic and hydrophobic oligomers. The oligomers are synthesized via a Pd-catalyzed Suzuki cross-coupling of 1,3-dibromo-5-hexyloxybenzene, and 3,3'-[(4,6-dibromo-1,3-phenylene)bis(oxy)]bis(propane-1-sulfonate) or 1,4-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzene. The good solubility and film-forming characteristics are achieved via the introduction of flexible hexyloxy side groups, and high ion exchange capacity (IEC) is achieved via the introduction of high density of alkyl sulfonated side groups. The HBP-b-0.5BPSBP has the highest IEC of 3.17 mmol/g, the highest proton conductivity of 43.5 mS/cm at 95 °C and 90% relative humidity (RH) and low methanol permeability of 6.45×10-7 cm2 /s. Meanwhile, crosslinked HBP-b-xBPSBP exhibits promising water uptake, swelling ratio and low methanol permeability. These characteristics are attributed to the crosslinked structure and the hydrophilic/hydrophobic nanophase separation morphology promoted by the poly(m-phenylene) main chains, flexible alkyl ether groups, and alkyl sulfonated side groups.