scholarly journals 1, 4 Dithiane 2, 5 Diol : An Versatile Monomer to Synthesis Aliphatic Random Copolyester with Biomedical Application

2019 ◽  
Vol 35 (2) ◽  
pp. 885-891
Author(s):  
Kalpana Balachandran ◽  
Nanthini Raveendiran ◽  
Margaret Marie John
Keyword(s):  
Biomedical Applications ◽  
Biomedical Application ◽  
Biological Properties ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Suitable Candidate ◽  
Melt Polycondensation ◽  
Direct Melt Polycondensation ◽  
Ft Ir ◽  
Antioxidant And Antimicrobial Activity

This article uses 1, 4-dithiane-2, 5-diol as a monomer to synthesize aliphatic random copolyester (PDDD).PDDD was synthesized by direct melt polycondensation method and characterized by FT-IR and 1H- NMR. The physical properties of PDDD were characterized by X-ray diffraction, differential scanning calorimetry, as well as viscosity and solubility measurements. The anticancer, antioxidant, and antimicrobial activity of PDDD were evaluated to investigate its potential biomedical applications. Generally, good results were obtained. It is evident that the copolyester exhibits favorable and tunable physical, thermal and biological properties and so is a suitable candidate for biomedical applications.

scholarly journals Advances in the Processing of UHMWPE-TiO2 to Manufacture Medical Prostheses via SPIF

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2022 ◽  
Author(s):  
Rodrigo Ortiz-Hernández ◽  
Nicolás A. Ulloa-Castillo ◽  
José M. Diabb-Zavala ◽  
Alejandro Estrada-De La Vega ◽  
Jorge Islas-Urbano ◽  
...  
Keyword(s):  
Compression Molding ◽  
Biological Properties ◽  
Dead Cell ◽  
X Ray Diffraction ◽  
Forming Process ◽  
Molding Process ◽  
Scanning Calorimetry ◽  
Ft Ir ◽  
Craniofacial Prosthesis ◽  
Ultra High Molecular Weight

This research focuses on developing a novel ultra high molecular weight polyethylene (UHMWPE) material reinforced with titanium dioxide (TiO 2 ) nanoparticles for producing craniofacial prostheses via an incremental sheet forming process (SPIF). First, UHMWPE-TiO 2 nanocomposite sheets were produced using incipient wetting and the compression molding process by considering different concentrations of TiO 2 nanoparticles. Then, the influence that the compression molding fabrication process has on the crystallinity and structural properties of the produced sample sheets was investigated. Experimental characterizations via scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier transform infrared (FT-IR), tensile mechanical testing, and live/dead cell viability assays provided data that show an enhancement of the physical, mechanical, and biological properties. Finally, modifications on the nanocomposite material properties due to the SPIF manufacturing processes of a craniofacial prosthesis are addressed.

scholarly journals Double Minerals Ions Co-substituted Nano-Hydroxyapatite Based Biocomposite Implant for Biomedical Applications

2021 ◽  
Vol 33 (6) ◽  
pp. 1409-1414
Author(s):  
R. Sangeetha ◽  
D. Madheswari ◽  
G. Priya ◽  
P. Lavanya
Keyword(s):  
Biomedical Applications ◽  
Biological Properties ◽  
Bone Tissue Regeneration ◽  
Calcium Deposition ◽  
X Ray Diffraction ◽  
Cell Transport ◽  
Transport Pathways ◽  
X Ray ◽  
High Antibacterial Activity ◽  
Ft Ir

The biocomposite of cerium(III)-copper(II) minerals co-substituted hydroxyapatite (Ce-Cu-HA)/ poly(methyl methacrylate) (PMMA) was developed using a process of solvent evaporation. The analysis of X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron microscope-energy dispersive X-Ray spectroscopy (SEM-EDX) confirmed the formation of Ce-Cu-HA in the PMMA matrix. In addition, the fabricated biocomposite demonstrated high antibacterial activity on Escherichia coli, which might be attributed to the action of Ce3+ and Cu2+ ions release on the substrate that blocks the cell transport pathways contributing to apoptosis. Biocomposites have been tested in osteoblast-like cells for their biological properties (biocompatibilty, alkaline phosphatase (ALP) activity and calcium deposition). Based on the present findings, it was proposed that Ce-Cu-HA/PMMA biocomposite could be a possible therapeutic candidate for bone tissue regeneration.

scholarly journals Synthesis and Characterization of N-Substituted Polyether-Block-Amide Copolymers

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 773
Author(s):  
Jyun-Yan Ye ◽  
Kuo-Fu Peng ◽  
Yu-Ning Zhang ◽  
Szu-Yuan Huang ◽  
Mong Liang
Keyword(s):  
Titanium Isopropoxide ◽  
Decomposition Temperature ◽  
Phenyl Isocyanate ◽  
Cross Linking ◽  
Resonance Spectroscopy ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Degradation Temperature ◽  
Melt Polycondensation ◽  
Structural Regularity

A series of N-substituted polyether-block-amide (PEBA-X%) copolymers were prepared by melt polycondensation of nylon-6 prepolymer and polytetramethylene ether glycol at an elevated temperature using titanium isopropoxide as a catalyst. The structure, thermal properties, and crystallinity of PEBA-X% were investigated using nuclear magnetic resonance spectroscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, wide angle X-ray diffraction, and thermogravimetric analysis. In general, the crystallinity, melting point, and thermal degradation temperature of PEBA-X% decreased as the incorporation of N-methyl functionalized groups increased, owing to the disruption caused to the structural regularity of the copolymer. However, in N-acetyl functionalized analogues, the crystallinity first dropped and then increased because of a new γ form arrangement that developed in the microstructure. After the cross-linking reaction of the N-methyl-substituted derivative, which has electron-donating characteristics, with poly(4,4′-methylenebis(phenyl isocyanate), the decomposition temperature of the resulting polymer significantly increased, whereas no such improvements could be observed in the case of the electro-withdrawing N-acetyl-substituted derivative, because of the incompleteness of its cross-linking reaction.

Liquid crystalline polyureas with oligo(ethylene glycol) sequences

e-Polymers ◽  
2010 ◽  
Vol 10 (1) ◽  
Author(s):  
Shahram Mehdipour-Ataei ◽  
Leila Akbarian-Feizi
Keyword(s):  
Liquid Crystalline ◽  
Spectroscopic Method ◽  
Polymerization Reaction ◽  
X Ray Diffraction ◽  
Subsequent Reaction ◽  
Scanning Calorimetry ◽  
Polar Solvents ◽  
X Ray ◽  
H Nmr ◽  
Ft Ir

AbstractA diamine monomer containing ester, amide and ether functional groups was prepared and its polymerization reaction with different diisocyanates to give main chain poly(ester amide ether urea)s was investigated. The monomer was synthesized via reaction of terephthaloyl chloride with 4-hydroxybenzoic acid and subsequent reaction of the resulted diacid with 1,8-diamino-3,6-dioxaoctane. The polymers were characterized by FT-IR and 1H-NMR spectroscopic method and elemental analysis. The resulting polymers exhibited excellent solubility in polar solvents. Crystallinity of the resulted polymers was evaluated by wide-angle X-ray diffraction (WXRD) method, and they exhibited semi-crystalline patterns. The glass transition temperatures (Tg) of the polymers determined by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) were in the range of 88-112 °C. The temperatures for 10% weight loss (T10) from their thermogravimetric analysis (TGA) curves were found to be in the range of 297-312 °C in air. Also the prepared polyureas showed liquid crystalline character.

Synthesis and Properties of Thermotropic Liquid Crystalline Polyesters with Flexible Polymethylene Spacer

2010 ◽  
Vol 428-429 ◽  
pp. 126-131
Author(s):  
Wei Zhong Lu ◽  
Chun Wei ◽  
Qui Shan Gao
Keyword(s):  
Optical Microscopy ◽  
Liquid Crystalline ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Structure Morphology ◽  
Temperature Ranges ◽  
Ft Ir ◽  
Diffraction Peaks ◽  
Ubbelohde Viscometer

Polymethylene bis(p-hydroxybenzoates) were prepared from methyl p-hydroxybenzoate and different diols by melted transesterification reaction. Three liquid crystalline polyesters were synthesized from terephthaloyl dichloride and polymethylene bis(p-hydroxybenzoates). Its structure, morphology and properties were characterized by Ubbelohde viscometer, Fourier transform infrared spectroscopy (FT-IR), Differential scanning calorimetry (DSC), polarized optical microscopy (POM) with a hot stage, and wide-angle X-ray diffraction (WAXD). Results indicated that the intrinsic viscosities were between 0.088 and 0.210 dL/g. Optical microscopy showed that the TLCP has a highly threaded liquid crystalline texture and a high birefringent schlieren texture character of nematic phase and has wider mesophase temperature ranges for all polyesters. DSC analysis were found that the melting point (Tm), isotropic temperature (Ti) of TLCPs decreased and the temperature range of the liquid crystalline phase became wider with increased number of methylene spacers in the polyester. The WAXD results showed that TLCPs owned two strong diffraction peaks at 2θ near 19° and 23°.

scholarly journals STARCH MEDIATED SYNTHESIS OF HYDROXYAPATITE NANOPARTICLE FOR BIOMEDICAL APPLICATIONS

2015 ◽  
Vol 2 (1) ◽  
pp. 15-17
Author(s):  
Indira J
Keyword(s):  
Biomedical Applications ◽  
Soluble Starch ◽  
Morphological Properties ◽  
Spherical Nanoparticles ◽  
Hydroxyapatite Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
Average Size ◽  
Controllable Size

Hydroxyapatite (HAP) nanoparticles with uniform morphologies and controllable size have been synthesized by template directed method. The environment and eco-friendly polysaccharide soluble starch is used as a template to regulate size and shape of the nanoparticles synthesized. Structural and morphological properties of as-synthesized hydroxyapatite nanoparticles have been examined through the techniques like Fourier Transform Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD) and Scanning Electron Microscopy(SEM), respectively. The results indicate that the obtained particles are uniform discrete spherical nanoparticles. The average size of the hydroxyapatite nanoparticles were ranged from 45 to 60 nm.

scholarly journals Biobased Engineering Thermoplastics: Poly(butylene 2,5-furandicarboxylate) Blends

Polymers ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 937 ◽  
Author(s):  
Niki Poulopoulou ◽  
George Kantoutsis ◽  
Dimitrios N. Bikiaris ◽  
Dimitris S. Achilias ◽  
Maria Kapnisti ◽  
...  
Keyword(s):  
Renewable Resources ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
Reactive Blending ◽  
Scanning Calorimetry ◽  
Melt Polycondensation ◽  
Poly Ethylene Terephthalate ◽  
Furandicarboxylic Acid ◽  
Poly Ethylene ◽  
Poly Propylene

Poly(butylene 2,5-furandicarboxylate) (PBF) constitutes a new engineering polyester produced from renewable resources, as it is synthesized from 2,5-furandicarboxylic acid (2,5-FDCA) and 1,4-butanediol (1,4-BD), both formed from sugars coming from biomass. In this research, initially high-molecular-weight PBF was synthesized by applying the melt polycondensation method and using the dimethylester of FDCA as the monomer. Furthermore, five different series of PBF blends were prepared, namely poly(l-lactic acid)–poly(butylene 2,5-furandicarboxylate) (PLA–PBF), poly(ethylene terephthalate)–poly(butylene 2,5-furandicarboxylate) (PET–PBF), poly(propylene terephthalate)–poly(butylene 2,5-furandicarboxylate) (PPT–PBF), poly(butylene 2,6-naphthalenedicarboxylate)-poly(butylene 2,5-furandicarboxylate) (PBN–PBF), and polycarbonate–poly(butylene 2,5-furandicarboxylate) (PC–PBF), by dissolving the polyesters in a trifluoroacetic acid/chloroform mixture (1/4 v/v) followed by coprecipitation as a result of adding the solutions into excess of cold methanol. The wide-angle X-ray diffraction (WAXD) patterns of the as-prepared blends showed that mixtures of crystals of the blend components were formed, except for PC which did not crystallize. In general, a lower degree of crystallinity was observed at intermediate compositions. The differential scanning calorimetry (DSC) heating scans for the melt-quenched samples proved homogeneity in the case of PET–PBF blends. In the remaining cases, the blend components showed distinct Tgs. In PPT–PBF blends, there was a shift of the Tgs to intermediate values, showing some partial miscibility. Reactive blending proved to improve compatibility of the PBN–PBF blends.

Compatibility between Magnesium Stearate and Pharmaceutical Acidic Active Compounds/Excipients with DSC

2020 ◽  
Vol 856 ◽  
pp. 190-197
Author(s):  
Pornsit Chaiya ◽  
Thawatchai Phaechamud
Keyword(s):  
Differential Scanning Calorimetry ◽  
Magnesium Stearate ◽  
X Ray Diffraction ◽  
Salt Form ◽  
Scanning Calorimetry ◽  
Powder Mixtures ◽  
X Ray ◽  
Pharmaceutical Excipients ◽  
Drug Compounds ◽  
Ft Ir

Compatibility investigation was performed between magnesium stearate and acidic drug compounds (ibuprofen, indomethacin and valproic acid) and acidic pharmaceutical excipients (lactic acid and citric acid) using differential scanning calorimetry (DSC). DSC study indicated the possible incompatibility for the mixture between magnesium stearate and any compounds. Alteration in DSC thermogram was found in all mixtures. The eutectic phenomenon was found in the powder mixture of magnesium stearate and ibuprofen. In addition, the presence of melting endothermic peak of stearic acid in other powder mixtures except the mixture of magnesium stearate and indomethacin indicating breakage of salt form of magnesium stearate. This alteration could relate to the influence on physicochemical properties of drug compounds and pharmaceutical excipients which powder x-ray diffraction (PXRD) and Fourier Transform Infrared Spectroscopy (FT-IR) should be further analyzed to confirm the interactions between compounds.

Stress-Induced Crystal-to-Crystal Transformations in High-Density Polyethylene-Layered Silicate Nanocomposites: A Spectroscopic Study

2005 ◽  
Vol 59 (9) ◽  
pp. 1148-1154 ◽  
Author(s):  
Spiros Tzavalas ◽  
Vasilis G. Gregoriou
Keyword(s):  
High Density Polyethylene ◽  
Mechanical Strain ◽  
Layered Silicate ◽  
High Density ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Polyethylene Matrix ◽  
Dsc Measurements ◽  
Infrared Measurements ◽  
Ft Ir

High-density polyethylene (HDPE)–clay nanocomposites have been prepared using the melt intercalation technique. Organically modified montmorillonite at various loadings (0.5–7%) was used as a nanoadditive. Fourier transform infrared spectroscopy (FT-IR) was utilized for the first time to monitor the stress-induced crystal-to-crystal transformations of the polyethylene matrix with respect to the clay loading as well as to the degree of mechanical strain. In addition, polarized infrared measurements revealed information on both the orientation and the stress-induced distortion of the crystals. It was concluded that the crystal-to-crystal transformations are hindered by the presence of the clay, which also prevented the crystals from orienting even at low clay loadings (1%). Finally, X-ray diffraction (XRD) and differential scanning calorimetry (DSC) measurements confirmed the presence of the stress-induced crystalline structures in agreement with the infrared measurements.

scholarly journals Preparation and Properties of Ginger Essential Oil β-Cyclodextrin/Chitosan Inclusion Complexes

Coatings ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 305 ◽  
Author(s):  
Yan Zhang ◽  
Hui Zhang ◽  
Fang Wang ◽  
Li-Xia Wang
Keyword(s):  
Particle Size ◽  
Essential Oil ◽  
Spray Drying ◽  
Small Particle Size ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Ft Ir ◽  
Thermal Stability Of ◽  
Scanning Electron

The ginger essential oil/β-cyclodextrin (GEO/β-CD) composite, ginger essential oil/β-cyclodextrin/chitosan (GEO/β-CD/CTS) particles and ginger essential oil/β-cyclodextrin/chitosan (GEO/β-CD/CTS) microsphere were prepared with the methods of inclusion, ionic gelation and spray drying. Their properties were studied by using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermo-gravimetry analysis (TGA), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The results showed that the particle size of GEO/β-CD composite was smaller than that of β-CD and GEO/β-CD/CTS particles were loose and porous, while the microsphere obtained by spray drying had certain cohesiveness and small particle size. Besides, results also indicated that β-CD/CTS could modify properties and improve the thermal stability of GEO, which would improve its application value in food and medical industries.

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