scholarly journals Medical Plant Extract Purification from Cadmium(II) Using Modified Thermoplastic Starch and Ion Exchangers

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4734
Author(s):  
Yi-Gong Chen ◽  
Qian Wang ◽  
Anna Wołowicz ◽  
Agnieszka Gładysz-Płaska ◽  
Monika Wawrzkiewicz ◽  
...  
Keyword(s):  
Gel Permeation Chromatography ◽  
Thermoplastic Starch ◽  
Point Of Zero Charge ◽  
Ion Exchangers ◽  
Toxic Heavy Metals ◽  
Cadmium Removal ◽  
Scanning Calorimetry ◽  
Butylene Succinate ◽  
Herbal Products ◽  
X Ray

Pure compounds extracted and purified from medical plants are crucial for preparation of the herbal products applied in many countries as drugs for the treatment of diseases all over the world. Such products should be free from toxic heavy metals; therefore, their elimination or removal in all steps of production is very important. Hence, the purpose of this paper was purification of an extract obtained from Dendrobium officinale Kimura et Migo and cadmium removal using thermoplastic starch (S1), modified TPS with poly (butylene succinate); 25% of TPS + 75% PBS (S2); 50% of TPS + 50% PLA (S3); and 50% of TPS + 50% PLA with 5% of hemp fibers (S4), as well as ion exchangers of different types, e.g., Lewatit SP112, Purolite S940, Amberlite IRC747, Amberlite IRC748, Amberlite IRC718, Lewatit TP207, Lewatit TP208, and Purolite S930. This extract is used in cancer treatment in traditional Chinese medicine (TCM). Attenuated total reflectance-Fourier transform infrared spectroscopy, thermogravimetric analysis with differential scanning calorimetry, X-ray powder diffraction, gel permeation chromatography, surface analysis, scanning electron microscopy with energy dispersive X-ray spectroscopy, and point of zero charge analysis were used for sorbent and adsorption process characterization, as well as for explanation of the Cd(II) sorption mechanism.

Synthesis and Crystallization of Poly(butylenes succinate-block-butylene sebacate)

2013 ◽  
Vol 750-752 ◽  
pp. 1313-1317
Author(s):  
Zong Hua Kang ◽  
Chang Lu Wang
Keyword(s):  
Crystal Structure ◽  
Gel Permeation Chromatography ◽  
Biodegradable Materials ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Butylene Succinate ◽  
X Ray ◽  
Gel Permeation ◽  
Biodegradable Poly

A series of aliphatic biodegradable poly (butylene succinate-block-butylene sebacate) (PBSuBSe) copolyesters were synthesized by incorporation of PBSe into the PBSu molecular chains. The molecular weight, crystallization behaviors and the crystal structure of the copolyesters were investigated by using gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WAXD), respectively. The copolyesters might be potentially useful as the biodegradable materials.

The Degradation of Poly (Butylene Succinate)/Natural Rubber Composites

2014 ◽  
Vol 934 ◽  
pp. 110-115
Author(s):  
Li Gao ◽  
Er Juan Zhi ◽  
Ping Li Wang ◽  
Jun Hui Ji
Keyword(s):  
Green Composites ◽  
X Ray Diffraction ◽  
Rubber Composites ◽  
Scanning Calorimetry ◽  
Butylene Succinate ◽  
X Ray ◽  
Weight Losses ◽  
Natural Rubber Composites ◽  
Degradation Test ◽  
Scanning Electron

In this study, poly (butylene succinate) (PBS)/nature rubber (NR) composites were prepared, and the effects of NR content on the biodegradability were evaluated by vermiculite-degradation test. X-ray Diffraction, differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) were used to characterize the degraded blends. The weight losses of PBS/NR composites are higher than that of pure PBS, and increased with adding NR content. The weight loss of 30% NR content composite after 120 days is 16.84%. The XRD and DSC results show that the crystallinity of PBS/NR composites increase after buried in vermiculite. These results were confirmed using SEM observations by the presence of many large holes and more cracks in the degradation surface morphology of the increasing content of NR. It was observed that PBS/NR composites are green-composites or eco-materials.

Synthesis and Characterization of Novel Polymer of Vinyl Carbazole Bearing Thiophene Groups

2012 ◽  
Vol 562-564 ◽  
pp. 512-515
Author(s):  
Yun Xian Yang ◽  
Ji Ping Yang ◽  
Bing Zhou ◽  
Jing Yu Zhang
Keyword(s):  
Conjugated Polymer ◽  
Suzuki Reaction ◽  
Gel Permeation Chromatography ◽  
High Glass Transition Temperature ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Infrared Spectrometer ◽  
Ft Ir ◽  
Fluorescence Spectrometer

Combination of vinyl carbazole and thiophene groups’ excellent thermal properties and optical properties, a novel polymer named poly(2,7-bi-2-thienyl-9-vinyl-9-H-carbazole) was synthesized via radical polymerization and Suzuki reaction. The polymer was characterized using Fourier transform infrared spectrometer(FT-IR), gel permeation chromatography(GPC), differential scanning calorimetry(DSC), and X-Ray fluorescence spectrometer(XRF). It was found that this π-conjugated polymer containing vinyl carbazole and thiophene groups gave a high glass transition temperature (Tg=251°C). This feature made poly(2,7-bi-2-thienyl-9-vinyl-9-H-carbazole) possessing an excellent thermal performance.

Influence of organoclay filler and dicumyl peroxide (DCP) on the properties of the low-density polyethylene (LDPE)/thermoplastic starch (TPS) blend

2020 ◽  
pp. 096739112097627
Author(s):  
Dalila Smail ◽  
Saliha Chaoui
Keyword(s):  
Thermoplastic Starch ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Dicumyl Peroxide ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
The Impact

In this study low-density polyethylene (LDPE)/thermoplastic starch (TPS)/nanoclay (O-Mt) nanocomposites were prepared by a melt blending process using a Brabender mixer. Dicumyl peroxide (DCP) and nanoclay (O-Mt) were studied to improve interfacial adhesion and to obtain the various desired properties of the nanocomposites. The structure and properties of the materials were studied by X-Ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and by tensile and Izod impact tests. X-ray diffraction analysis of the nanocomposites showed that the characteristic peaks of the clay were shifted to the lower angles, indicating an intercalated structure in the presence of dicumyl peroxide (DCP). The TGA curve indicated an improvement in the thermal stability of the materials with the amount of silicate and DCP. The mechanical properties of the materials were improved as a consequence of the increase in phase adhesion which gave an improvement in crystallinity confirmed by DSC. In addition, the impact strength of the modified materials was improved compared to the original materials. A modification of morphology as well as roughness was demonstrated by SEM and AFM.

scholarly journals Structural and Thermal Properties of Starch Plasticized with Glycerol/Urea Mixture

2021 ◽  
Author(s):  
Magdalena Paluch ◽  
Justyna Ostrowska ◽  
Piotr Tyński ◽  
Waldemar Sadurski ◽  
Marcin Konkol
Keyword(s):  
Thermal Properties ◽  
Chemical Structure ◽  
Gel Permeation Chromatography ◽  
Xrd Analysis ◽  
Thermoplastic Starch ◽  
X Ray Diffraction ◽  
Screw Extruder ◽  
X Ray ◽  
Twin Screw ◽  
Starch Retrogradation

AbstractThe paper presents the results of research on the influence of used plasticizing system on the structural and thermal properties of thermoplastic starch (TPS). The thermoplastic starch granulate was obtained by extrusion of native starch in the presence of a plasticizing system using a twin-screw extruder. Glycerol and urea were used as plasticizers in various proportions. In order to evaluate the effectiveness of the starch plasticization process, changes in its chemical structure were analyzed by infrared spectroscopy (FTIR), gel permeation chromatography (GPC) and X-ray diffraction (XRD). TPS thermal stability was determined by thermogravimetric analysis (TGA). An improvement in the efficiency of the plasticization process has been found for a urea-containing plasticizing system compared to the composition of starch plasticized only with glycerol. In addition, the XRD analysis confirms the beneficial effect of urea on the inhibition of starch retrogradation process.

scholarly journals Aromatic polyesters with photosensitive side chains: Synthesis, characterization and properties

2016 ◽  
Vol 81 (6) ◽  
pp. 673-685 ◽  
Author(s):  
Marioara Nechifor
Keyword(s):  
Gel Permeation Chromatography ◽  
Dicarboxylic Acids ◽  
Nitrogen Atmosphere ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Good Solubility ◽  
Tosyl Chloride ◽  
Fourier Transform Ir ◽  
Aromatic Dicarboxylic Acids ◽  
Aromatic Polyesters

New aromatic polyesters with photosensitive groups in their pendant chains were prepared from a diphenol carrying as substituent a cinnamoyl group extended with a flexible oxyethyleneoxy spacer and different aromatic dicarboxylic acids via direct polyesterification reaction in the presence of tosyl chloride/pyridine/dimethylformamide system as condensing agent. The resulting polyesters were characterized using Fourier-transform IR, proton and carbon nuclear magnetic resonance and ultraviolet spectroscopy, differential scanning calorimetry, thermogravimetric analysis, wide-angle X-ray diffractometry, gel permeation chromatography, viscosity measurement and solubility test. These polyarylates had moderate inherent viscosities ranging from 0.37 to 0.54 dL g-1, good solubility in polar aprotic solvents, and afforded transparent, colorless and apparently tough films by casting from their solutions. Their glass-transition temperatures ranged from 136 to 154?C. All of them did not show significant decomposition below 320?C and retained 38-47 % weight at 700?C in nitrogen atmosphere. The presence of cinnamoyl chromophore endowed these polymers with the ability to react to ultraviolet light which resulted in photodimerization between cinnamoyl side groups upon irradiation at l = 365 nm and cross-linking the polymers chains in the absence of photo-initiators or photo-sensitizers. As a consequence, the polymer films became insoluble in organic solvents.

scholarly journals Preparation, Mechanical, and Thermal Properties of Biodegradable Polyesters/Poly(Lactic Acid) Blends

2010 ◽  
Vol 2010 ◽  
pp. 1-8 ◽  
Author(s):  
Peng Zhao ◽  
Wanqiang Liu ◽  
Qingsheng Wu ◽  
Jie Ren
Keyword(s):  
Lactic Acid ◽  
Gel Permeation Chromatography ◽  
Poly Lactic Acid ◽  
Mechanical And Thermal Properties ◽  
Scanning Calorimetry ◽  
Butylene Succinate ◽  
Biodegradable Polyesters ◽  
H Nmr ◽  
Melt Polycondensation ◽  
Twin Screw

Series of biodegradable polyesters poly(butylene adipate) (PBA), poly(butylene succinate) (PBS), and poly(butylene adipate-co-butylene terephthalate) (PBAT) were synthesized successfully by melt polycondensation. The polyesters were characterized by Fourier transform infrared spectroscopy (FTIR),1H-NMR, differential scanning calorimetry (DSC), and gel permeation chromatography (GPC), respectively. The blends of poly(lactic acid) (PLA) and biodegradable polyester were prepared using a twin screw extruder. PBAT, PBS, or PBA can be homogenously dispersed in PLA matrix at a low content (5–20 wt%), yielding the blends with much higher elongation at break than homo-PLA. DSC analysis shows that the isothermal and nonisothermal crystallizabilities of PLA component are promoted in the presence of a small amount of PBAT.

In Vitro Degradation of Poly-L-DL-Lactic Acid (PLDLLA) after Two Processing Methods

2014 ◽  
Vol 20 ◽  
pp. 45-64 ◽  
Author(s):  
Maria Elisa Rodrigues Coimbra ◽  
Márcia Gouvea Bernardes ◽  
Carlos Nelson Elias ◽  
Paulo Guilherme Coelho
Keyword(s):  
Lactic Acid ◽  
Gel Permeation Chromatography ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Processing Methods ◽  
X Ray ◽  
Amorphous Content ◽  
Before And After

This study evaluated thein vitrodegradation of pellet, powder and plates of poly-L-DL-lactic acid (PLDLLA) after two processing methods. Part of the material was reduced to powder by cryogenic milling and part of it molded injected in plate form. The crystallinity was evaluated by Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), and Gel Permeation Chromatography (GPC) before and after immersion in simulated body fluid for 30, 60, and 90 days. The glass transition temperature (Tg) of the pellets and the powder were 61.5°C, 66°C. The Tgs of the plates ranged from 59.55°C to 63.06°C. Their endothermic peaks were observed at 125°C and 120°C, which was not identified to the plates samples. The FTIR spectrum showed bands of amorphous and crystalline content. The XRD results showed a peak related to the crystalline content, and a wide reflection related to the amorphous content. The milling process increased the crystallinity and the molding injection decreased it.

Electron microscopy of crystalline structure in thermotropic random copolymers

1991 ◽  
Vol 49 ◽  
pp. 1054-1055
Author(s):  
Afzana Anwer ◽  
S. Eilidh Bedford ◽  
Richard J. Spontak ◽  
Alan H. Windle
Keyword(s):  
Electron Microscopy ◽  
Crystalline Structure ◽  
Liquid Crystalline ◽  
Elevated Temperatures ◽  
Random Copolymers ◽  
Molecular Characteristics ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Identical Monomer ◽  
Periodic Layer

Random copolyesters composed of wholly aromatic monomers such as p-oxybenzoate (B) and 2,6-oxynaphthoate (N) are known to exhibit liquid crystalline characteristics at elevated temperatures and over a broad composition range. Previous studies employing techniques such as X-ray diffractometry (XRD) and differential scanning calorimetry (DSC) have conclusively proven that these thermotropic copolymers can possess a significant crystalline fraction, depending on molecular characteristics and processing history, despite the fact that the copolymer chains possess random intramolecular sequencing. Consequently, the nature of the crystalline structure that develops when these materials are processed in their mesophases and subsequently annealed has recently received considerable attention. A model that has been consistent with all experimental observations involves the Non-Periodic Layer (NPL) crystallite, which occurs when identical monomer sequences enter into register between adjacent chains. The objective of this work is to employ electron microscopy to identify and characterize these crystallites.

Studies on the Preparation, Characterization and Solubility of -Cyclodextrin-Roxythromycin Inclusion Complexes

2009 ◽  
Vol 2 (2) ◽  
pp. 523-530
Author(s):  
D. Nagasamy Venkatesh ◽  
S. Karthick ◽  
M. Umesh ◽  
G. Vivek ◽  
R.M. Valliappan ◽  
...  
Keyword(s):  
Dissolution Rate ◽  
Inclusion Complexes ◽  
Phase Solubility ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Ir Studies ◽  
Poorly Soluble ◽  
Poorly Soluble Drug

Roxythromycin/ β-cyclodextrin (Roxy/ β-CD) dispersions were prepared with a view to study the influence of β-CD on the solubility and dissolution rate of this poorly soluble drug. Phase-solubility profile indicated that the solubility of roxythromycin was significantly increased in the presence of β-cyclodextrin and was classified as AL-type, indicating the 1:1 stoichiometric inclusion complexes. Physical characterization of the prepared systems was carried out by differential scanning calorimetry (DSC), X-ray diffraction studies (XRD) and IR studies. Solid state characterization of the drug β-CD binary system using XRD, FTIR and DSC revealed distinct loss of drug crystallinity in the formulation, ostensibly accounting for enhancement of dissolution rate.

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