scholarly journals Study of the Biodegradation of PLA/PBAT Films after Biodegradation Tests in Soil and the Aqueous Medium

2021 ◽  
Vol 12 (1) ◽  
pp. 833-846
Keyword(s):  
Contact Angle ◽  
Aqueous Medium ◽  
Visual Analysis ◽  
Fourier Transforms ◽  
Scanning Calorimetry ◽  
Thermal Compression ◽  
Hydrophilic Character ◽  
Ft Ir ◽  
Fourier Transforms Infrared Spectroscopy ◽  
Biodegradation In Soil

The intense consumption of conventional plastics has been generating a series of problems for nature due to the accumulation of municipal solid waste because of its difficult degradation. Therefore, the use of biodegradable polymers becomes a good option to minimize these effects. Poly (lactide acid)/poly(butylene adipate-co-terephthalate) (PLA/PBAT) is a biodegradable blend that can be used mainly in applications that have a short shelf life. So, it is important to know the total biodegradation time of this blend. For this reason, PLA/PBAT films (1.5 x 1.5 x 0.15 cm) were produced by thermal compression molding to be subjected to biodegradation tests in soil and aqueous medium for 180 days. The films were characterized by visual analysis, weight loss measurements, differential scanning calorimetry (DSC), Fourier transforms infrared spectroscopy (FT-IR), contact angle, and scanning electron microscopy (SEM). DSC showed an increase of 0.7% in PLA crystallinity subjected to the aqueous medium, while FT-IR showed a reduction in the bands at 1710 cm-1 and 1100 cm-1, as a result of hydrolysis for both methodologies. The blend's hydrophilic character was increased after both degradation processes, presenting a reduction of 34.5% in the contact angle after biodegradation in soil. From the results, it was possible to conclude that PLA/PBAT films did not degrade completely, as expected, but showed signs that indicated the beginning of the degradation. The degradation was more effective in the aqueous medium.

Characterization and Evaluation of Ca/Al LDHs Adsorbents Synthesized by a One-Step Hydrothermal Method for Congo Red Removal

2020 ◽  
Vol 977 ◽  
pp. 195-200
Author(s):  
Hong Tham Thi Nguyen ◽  
Dao Thi To Uyen ◽  
Duy Chinh Nguyen ◽  
Van Thuan Tran ◽  
Tri Duc Lam ◽  
...  
Keyword(s):  
Congo Red ◽  
Fourier Transforms ◽  
X Ray Diffraction ◽  
Anionic Dyes ◽  
One Step ◽  
Ft Ir ◽  
Fourier Transforms Infrared Spectroscopy ◽  
Hydrothermal Approach ◽  
Double Hydroxide ◽  
Hydrolysis Of

We investigated the fabrication of Ca/Al layered double hydroxide (LDHs) via a one-step hydrothermal approach with slow hydrolysis of urea at a low temperature without further annealing required. The as-synthesized Ca/Al LDHs nanostructures obtained were defined using Fourier transforms infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), powder X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results demonstrated that Ca/Al LDHs exhibit excellent adsorption performance on Congo red anionic dyes in aqueous solution. The adsorption capacity of the Ca/Al LDHs toward Congo red was found to be 59.41 mg/g.

scholarly journals Enhancement of Solubility BCS Class II and IV Pharmaceuticals by Liqusolid Technique: A review

2020 ◽  
Vol 2 (2) ◽  
pp. 77
Author(s):  
Dwi Retno Sari ◽  
Yoga Windhu Wardhana ◽  
Taofik Rusdiana
Keyword(s):  
Contact Angle ◽  
Drug Release ◽  
Manufacturing Industry ◽  
Fourier Transforms ◽  
Class Ii ◽  
Production Costs ◽  
Active Pharmaceutical Ingredients ◽  
Scanning Calorimetry ◽  
Pharmaceutical Ingredients ◽  
Volatile Solvents

Many techniques can be used to improve drug solubility, which is the development of the liquisolid technique. This technique has a mechanism for increasing the surface area of the drug as well as wetting from the addition of non-volatile solvents resulting in a lower surface tension and contact angle, so the solubility and drug release very increases. Liquisolid tablets show a lower contact angle compared to the conventional tablets. The liquisolid technique approach is also promising because the process is simple in making low production costs and allows the manufacturing industry, including non-volatile solvents, fillers, dryers, and disintegrants. Liquisolid characterized by specific instruments such as powder x-ray diffraction (PXRD), Fourier transforms infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and scanning electron microscope (SEM). Several liquisolid techniques are described in this review. The liquisolid technique is proven and able to change the physicochemical properties of active pharmaceutical ingredients, especially the solubility, drug release, and stability of the formula so that this technique can be a solution for class II and IV BCS pharmaceutical active drug classes.Keywords: Active Pharmaceutical Ingredients, Contact Angle, Solubility, Drug Release, Stability, Liquisolid Technique

scholarly journals Acid Treatment Halloysite Nanoclay: Eco-Friendly Heterogeneous Catalyst for the Synthesis of Pyrrole Derivatives

Proceedings ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 17
Author(s):  
Ali Maleki ◽  
Zoleikha Hajizadeh
Keyword(s):  
Infrared Spectroscopy ◽  
Acid Treatment ◽  
High Efficiency ◽  
Fourier Transforms ◽  
Halloysite Nanotubes ◽  
Hydroxyl Groups ◽  
Simple Method ◽  
Pyrrole Derivatives ◽  
Ft Ir ◽  
Fourier Transforms Infrared Spectroscopy

In this study, halloysite nanotubes (HNTs) as a green and available nano-mineral were used. The hydroxyl groups of HNTs were increased by acid treatment. So, the efficiency of HNTs was improved. The catalyst application of acid treatment HNTs was investigated in the synthesis of pyrrole as an important heterocycle compound. The catalyst was characterized by Fourier transforms infrared spectroscopy (FT-IR). Easy and simple method, high efficiency and eco-friendly are the advantages of this report.

scholarly journals Polydimethylsiloxane and Castor Oil Comodified Waterborne Polyurethane

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Xuan Ji ◽  
Yanming Zhou ◽  
Baoling Zhang ◽  
Caiying Hou ◽  
Guozhang Ma
Keyword(s):  
Thermal Stability ◽  
Castor Oil ◽  
Water Resistance ◽  
Fourier Transforms ◽  
Protective Coatings ◽  
Average Particle Size ◽  
Waterborne Polyurethane ◽  
Average Particle ◽  
Ft Ir ◽  
Fourier Transforms Infrared Spectroscopy

In view of both improving properties of waterborne polyurethane (WPU) and sufficient utilization of renewable resources, a series of polydimethylsiloxane (PDMS) and castor oil (C.O.) comodified anionic WPUs with internal cross-linking was prepared through a prepolymer mixing process. The chemical structure of synthesized polymers was characterized by Fourier transforms infrared spectroscopy (FT-IR). In comparison with traditional linear WPU synthesized from petroleum-based polyols, these novel WPU films exhibited superior properties in solvent and water resistance, thermal stability, and mechanical strength, which suggest promising applications of these new environmentally friendly materials, particularly in the area of decorative and protective coatings. In addition, the results showed that with the increase in PDMS content in these co-modified WPUs the average particle size, the water resistance, and the thermal stability increased accordingly while the solvent resistance and the mechanical properties decreased.

Octaepoxysilsesquioxane Cured by Different Curing Agents

2011 ◽  
Vol 84-85 ◽  
pp. 519-523
Author(s):  
Zeng Ping Zhang ◽  
Guo Zheng Liang ◽  
Shuan Fa Chen
Keyword(s):  
Fourier Transforms ◽  
Condensation Reaction ◽  
Excellent Thermal Stability ◽  
Inorganic Hybrid ◽  
Hydrolysis And Condensation ◽  
Ft Ir ◽  
Fourier Transforms Infrared Spectroscopy ◽  
Curing Agents ◽  
Oligomeric Silsesquioxane ◽  
Epoxy Groups

Polyhedral oligomeric silsesquioxane (POSS) can be used to prepare organic/inorganic hybrid materials. Octaepoxysilsesquioxane (E-POSS) containing eight reactive epoxy groups in a molecule was synthesized through the hydrolysis and condensation reaction of γ-[(2,3)-epoxypropoxy] propyltrimethoxysilicane. In this study, E-POSS was cured with 4,4'-Diaminodiphenylsulfone diamine (DDS) and methylnadic anhydride (MNA) , respectively. The curing reactions for both systems were monitored by Fourier transforms infrared spectroscopy (FT-IR). And the thermal properties of the cured systems were studied by Thermogravimetric analysis (TGA). The disappearance of the epoxy groups showed that either DDS or MNA was able to cure E-POSS into an organic-inorganic hybrid system with excellent thermal stability.

FACILE SYNTHESIS OF HYDROXYLAPATITE NANOSTRUCTURES WITH VARIOUS MORPHOLOGIES

NANO ◽  
2009 ◽  
Vol 04 (03) ◽  
pp. 165-170 ◽  
Author(s):  
XIAO-JUN HU ◽  
JIN-KU LIU ◽  
XIAO-YAN QIN ◽  
JIA HUANG ◽  
YI YI
Keyword(s):  
Crystal Engineering ◽  
Fourier Transforms ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solution Approach ◽  
Engineering Research ◽  
Practical Applications ◽  
Transmission Electron ◽  
Ft Ir ◽  
Fourier Transforms Infrared Spectroscopy

The hydroxylapatite nanostructures with different morphologies have been synthesized by a facile solution approach. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) technologies, and Fourier transforms infrared spectroscopy (FT-IR). The control mechanism of the hydroxylapatite with various morphologies nanostructures was investigated. Some practical experimental conclusions could be obtained, which were expected to have potential values in crystal engineering research and practical applications.

Structure and properties of polytetrafluoroethylene (PTFE) fibers

e-Polymers ◽  
2017 ◽  
Vol 17 (3) ◽  
pp. 215-220 ◽  
Author(s):  
Ruiliu Wang ◽  
Guangbiao Xu ◽  
Yuechao He
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Cross Sections ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Structure And Properties ◽  
Scanning Calorimetry ◽  
Water Contact ◽  
Excellent Thermal Stability ◽  
Ft Ir

AbstractStructure and properties of polytetrafluoroethylene (PTFE) fibers were characterized thoroughly by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analyzing (TG) and water contact angle measurement. It was found that the longitudinal surface of the fiber was not smooth and was full of grooves. The cross sections of fibers were sheet-like and irregular. The infrared spectrum of PTFE fibers was the same as that of PTFE films except the 626 cm-l bands which were associated with the helix-reversal defect. The range of fineness distribution (2.09–11.50 dtex) was wide and the average strength was 1.37 cN/dtex. PTFE fibers began to be decomposed at 508.6°C and showed excellent thermal stability. The water contact angle of fibers layers was 120° indicating it to be a hydrophobic material. All these results provide a theoretical foundation for applications of PTFE fibers.

Controllable Preparation of Zinc Phosphate Materials with Different Morphologies and Particle Size

2014 ◽  
Vol 1078 ◽  
pp. 20-24
Author(s):  
Jiang Jie Wang ◽  
Xiao Hong Yang ◽  
Jing Wang ◽  
Qin Tong ◽  
Jin Ku Liu
Keyword(s):  
Particle Size ◽  
Zinc Phosphate ◽  
Fourier Transforms ◽  
Control Mechanism ◽  
Functional Materials ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
Fourier Transforms Infrared Spectroscopy ◽  
Controllable Preparation

Zinc phosphate materials which have different morphologies, particle size and good crystalline were prepared via an effective template method. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transforms infrared spectroscopy (FT-IR). The control mechanism of the zinc phosphate was investigated. Some practical experimental conclusions could be obtained, which were expected to have potential values in synthesis of functional materials.

scholarly journals A Novel Efficient MPEG-Chitosan/HA Biopolymer for Adsorption of the Anticancer SN-38 Liquid Dispersions: Kinetics, Thermodynamic and Ex-Vivo Release Evaluation

2021 ◽  
Vol 65 (4) ◽  
Author(s):  
Faezeh Sharifi ◽  
Mansour Jahangiri ◽  
Pedram Ebrahimnejad
Keyword(s):  
Drug Delivery ◽  
Fourier Transforms ◽  
Ex Vivo ◽  
Low Cost ◽  
Order Kinetic ◽  
Scanning Calorimetry ◽  
Release Process ◽  
El Sistema ◽  
Diffusion Phenomena ◽  
Ft Ir

Abstract. Amongst several drug delivery schemes for perfect drug delivery comprise biocompatibility, selective aiming of cancer cells, low-cost, and safe process of nanoparticle preparation. In this work, a new mPEG-chitosan/HA biopolymer was prepared as adsorbent nanoparticles (mNPs) for an efficient drug delivery system.  The mNPs was synthesized by conjugating poly (ethylene glycol) methyl ether (mPEG) to chitosan and prepared through ionic gelation between mPEG-chitosan and hyaluronic acid (HA). The prepared mNPs were used to adsorption/release of 7-ethyl-10-hydroxycamtothecin (SN-38) from its liquid dispersions. The mNPs adsorbent was characterized by Fourier transforms infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM). The results demonstrated that the adsorption isotherm of SN-38 on mNPs follows Langmuir model, and the adsorption capacity was 346.511 mg g-1. Besides, the pseudo-first order kinetic well fitted the equilibrium data. Further, thermodynamic parameters including ΔH, ΔG and ΔS were calculated which demonstrated that the physical spontaneous adsorption was prevailing. In addition, the ex- vivo release of SN-38 from mNPs were in good agreement with Korsmeyer-Peppas equation indicating the drug release process was governed by diffusion phenomena. The above results revealed that mNPs containing SN-38 was a good candidate for the drug delivery systems.   Resumen. Dentro de las diferentes propiedades importantes de los sistemas de liberación de fármacos se encuentran la biocompatibilidad, el ataque selectivo a las células cancerosas, el bajo costo y los procesos adecuados de preparación de nanopartículas. En este trabajo, un nuevo biopolímero de mPEG-chitosan/HA se preparó en la forma de nanopartículas (mNPs) para el uso como un sistema de liberación controlada de fármacos. Las nanopartículas se sintetizaron incorporando el éter metílico de poli(etilenglidol) al quitosano, y se prepararon a través de la gelación iónica entre el mPEG-quitosano y el ácido hialurónico (HA). Las nanopartículas así preparadas se probaron en su efectividad para la absorción y liberación de 7-etil-10-hidroxicamtotecina (SN-38) en forma de dispersiones líquidas. El absorbente hecho a partir de las nanopartículas se caracterizó mediante espectroscopía infrarroja de transformada de Fourier (FT-IR), calorimetría diferencial de barrido (DSC) y microscopía electrónica de barrido (SEM). Se encontró que la isoterma de adsorción de la muestra de nanopartículas conteniendo SN-38 se ajusta al modelo de Langmuir, siendo el valor de la capacidad de adsorción de 346.511 mg g-1. El modelo cinético de seudo primer orden se ajusta adecuadamente a los datos obtenidos al equilibrio. Más aún, los parámetros termodinámicos tales como ΔH, ΔG and ΔS se pudieron calcular, lo que indica que la adsorción física espontánea es el mecanismo que prevalece. Además, los datos de liberación ex- vivo de SN-38 a partir de las nanopartículas se pueden ajustar a la ecuación de Korsmeyer-Peppas, indicando que el proceso de liberación del fármaco está gobernado por un proceso de difusión. Los resultados anteriores indican que el sistema de nanopartículas conteniendo SN-38 es un buen candidato para desarrollar un sistema de liberación controlada de fármacos. 

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