scholarly journals Development of Nervilia fordii Extract-Loaded Electrospun PVA/PVP Nanocomposite for Antioxidant Packaging

Foods ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1728
Author(s):  
Peng Wen ◽  
Teng-Gen Hu ◽  
Yan Wen ◽  
Ke-Er Li ◽  
Wei-Peng Qiu ◽  
...  
Keyword(s):  
Food Packaging ◽  
Thermo Gravimetric Analysis ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
Poly Vinyl Alcohol ◽  
Total Phenolic ◽  
Gravimetric Analysis ◽  
Thermo Gravimetric ◽  
Phenolic And Flavonoid ◽  
Thermal Stability Of

An ethyl acetate extract from of Nervilia fordii (NFE) with considerable suppression activity on lipid peroxidation (LPO) was first obtained with total phenolic and flavonoid contents and anti-LPO activity (IC50) of 86.67 ± 2.5 mg GAE/g sample, 334.56 ± 4.7 mg RE/g extract and 0.307 mg/mL, respectively. In order to improve its stability and expand its application in antioxidant packaging, the nano-encapsulation of NFE within poly(vinyl alcohol) (PVA) and polyvinyl(pyrrolidone) (PVP) bio-composite film was then successfully developed using electrospinning. SEM analysis revealed that the NFE-loaded fibers exhibited similar morphology to the neat PVA/PVP fibers with a bead-free and smooth morphology. The encapsulation efficiency of NFE was higher than 90% and the encapsulated NFE still retained its antioxidant capacity. Fourier transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD) analysis confirmed the successful encapsulation of NFE into fibers and their compatibility, and the thermal stability of which was also improved due to the intermolecular interaction demonstrated by thermo gravimetric analysis (TGA). The ability to preserve the fish oil’s oxidation and extend its shelf-life was also demonstrated, suggesting the obtained PVA/PVP/NFE fiber mat has the potential as a promising antioxidant food packaging material.

Study on the thermal stability of Controlled Permeability Formwork

2011 ◽  
Vol 374-377 ◽  
pp. 1426-1429
Author(s):  
Xiao Meng Guo ◽  
Jian Qiang Li ◽  
Xian Sen Zeng ◽  
De Dao Hong
Keyword(s):  
Thermal Stability ◽  
Thermal Properties ◽  
Dynamic Mechanical Analysis ◽  
Thermo Gravimetric Analysis ◽  
Mechanical Analysis ◽  
Gravimetric Analysis ◽  
Construction Work ◽  
Thermo Gravimetric ◽  
Excellent Thermal Stability ◽  
Thermal Stability Of

In this study, the thermal properties of a kind of new geotextile materials, so called controlled permeable formwork (CPF), were studied. Thermo-gravimetric analysis showed that the weight of CPF didn’t change much between 0~350 °C. Dynamic mechanical analysis showed that the storage modulus of CPF reduced from 25 MPa to around 10 MPa when the temperature rose to above 100 °C. The strength of sample decreased slightly with the increase of the temperature. The breaking elongation changed slightly with a maximum at 80 °C. The CPF showed excellent thermal stability and was suitable for general use in construction work.

Study of the Kinetics of Hydration Process of Anhydrite Using External Exciters

2013 ◽  
Vol 838-841 ◽  
pp. 2342-2345 ◽  
Author(s):  
Dominik Gazdič ◽  
Marcela Fridrichová ◽  
Karel Kalivoda ◽  
Jana Stachová
Keyword(s):  
Thermo Gravimetric Analysis ◽  
Hydrated Lime ◽  
Xrd Analysis ◽  
Sodium Sulphate ◽  
Hydration Process ◽  
Gravimetric Analysis ◽  
Technological Properties ◽  
Thermo Gravimetric ◽  
Kinetics Of

Due to the very gradual hydration of anhydrites and their very low strengths, modification of the properties of anhydrite by a suitable external exciter was resolved within the work. The experimental work was conducted on natural anhydride, and as possible exciters for hydration, the following products were selected and tested: water-free sodium sulphate; Portland cement CEM I 42,5 R; hydrated lime CL 90 Carmeuse. The dose of the exciter was consistent, i.e. 4.5 wt%. The affect on the increased speed of the hydrating process and the quality of the technological properties was monitored. The catalytic effect was evaluated by monitoring the course of the hydration process (using XRD analysis and thermo-gravimetric analysis) and also on the basis of the achieved technological properties.

Experimental Investigation of Kevlar KM2Plus Nano-Reinforced Laminated Composite Thermo-Mechanical Properties

2016 ◽  
Author(s):  
Abdel-Hamid I. Mourad ◽  
Omar G. Ayad ◽  
Ashfakur Rahman ◽  
Ali Hilal-Alnaqbi ◽  
Basim I. Abu-Jdayil
Keyword(s):  
Mechanical Properties ◽  
Thermo Gravimetric Analysis ◽  
Laminated Composite ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Thermo Gravimetric ◽  
Three Point Bending ◽  
Multi Walled Carbon Nanotube ◽  
Thermal Stability Of

This work is concerned with the synthesis and characterization of Multi-Walled Carbon Nanotube (MWCNT) reinforced Kevlar KM2Plus composites with various MWCNT contents (0.2, 0.3, 0.4, 0.5, 0.6, and 0.8 wt. %), by the wet lay-up technique. These samples were experimentally investigated for their thermo-mechanical properties using Thermo-Gravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), tensile testing and three-point bending techniques. The mechanical properties showed remarkable improvement with increasing MWCNT wt.% up to certain content. The results revealed that the addition of MWCNT fillers has no significant effect on the thermal stability of the composites.

Polymer nanocomposites reinforced with C60 fullerene: effect of hydroxylation

2011 ◽  
Vol 45 (25) ◽  
pp. 2595-2601 ◽  
Author(s):  
Tsuyoshi Saotome ◽  
Ken Kokubo ◽  
Shogo Shirakawa ◽  
Takumi Oshima ◽  
H. Thomas Hahn
Keyword(s):  
Thermal Stability ◽  
Thermo Gravimetric Analysis ◽  
Nanocomposite Films ◽  
Light Transmittance ◽  
C60 Fullerene ◽  
Partial Hydrolysis ◽  
Poly Vinyl Alcohol ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Thermal Stability Of

Novel nanocomposite films of polycarbonate (PC) with fullerene derivatives, such as pristine fullerene C60 and polyhydroxylated-fullerenes, C60(OH)12 and C60(OH)36, were prepared. The optical, thermal, and mechanical properties of the composites were measured. Nanocomposite films of poly (vinyl alcohol) (PVA) with C60(OH)36 were prepared as a reference to show how improved dispersion of the nanofiller affects the overall transparency of the composites. Ultraviolet-visible spectroscopy showed that the addition of hydroxylated fullerenes did not affect visible light transmittance of the films significantly in the range of 400–800 nm. Differential scanning calorimetry (DSC) and thermo–gravimetric analysis (TGA) measurements showed the increased thermal stability of PC/C60(OH)12 film as compared to pristine PC film. This phenomenon was explained by the rigid polymer interphase regions formed around C60(OH)12 due to the plausible hydrogen bonding and hydrophobic interaction. On the other hand, the lower thermal stability of PC–C60(OH)36 was assumed to be caused by large agglomeration of the C60(OH)36 particles and the partial hydrolysis of the polycarbonate matrix. Tensile testing of the composites showed reduction in elongation at break and yield tensile strength. These results may be caused by the particle agglomerations which act as the initiation points for cracks.

scholarly journals Physicomechanical and Operational Properties Polyurethane Thermal Panels

2020 ◽  
Vol 9 (4) ◽  
pp. 446-454
Keyword(s):  
Ir Spectroscopy ◽  
Uv Radiation ◽  
Thermo Gravimetric Analysis ◽  
Operation Time ◽  
Heat Stability ◽  
Gravimetric Analysis ◽  
Thermo Gravimetric ◽  
Operational Characteristics ◽  
Lower Temperature ◽  
Thermal Stability Of

Evaluation of consumer properties of polyurethane thermal panels is the goal of the work. Physico-mechanical and operational characteristics of thermal panels are determined to achieve the purpose of the work. Methods of IR spectroscopy and thermo gravimetric analysis were used to study the structure of the samples. Satisfactory consumer properties of the studied thermo panels are brought out: compliance of clinker with the DIN EN 121 standard; absence of visual defects and change of color of thermo panels after 50 cycles of freezing-thawing; absence of changing color of thermo panels after influence of UV of radiation with the wavelength of 240-320 nanometers within 607 hours 30 minutes; high values of coefficients of sound absorption in the frequency range from 600 to 1600 Hz; low heat conductivity of the FPU layer. The influence of UV-radiation on thermal stability of foamed polyurethane is valued. Thermal analysis methods and IR spectroscopy are used to assess the degree of UV - destruction of polyurethane foam. At destruction of foamed polyurethane there is a rupture of chemically weak communication and formation of alcohols, air, olefins. The results of IR-spectroscopy illustrate the beginning of the processes of destruction of samples of FPU under the influence of UV-radiation. Using the thermo gravimetric analysis the research of the FPU thermal properties under the influence of UV - radiations is conducted. It is established that compositions from FPU under the influence of UV- radiation have lower temperature of the beginning of decomposition, than initial material. The influence of UV-radiation on heat stability of the studied compositions is shown. The possible mechanism of destruction of FPU is confirmed in the research. The DSС method has estimated the resistance of FPU to the oxidizing influence characterizing the material operation time. The studied consumer properties of thermal panels show that they can be used in civil engineering as effective protection structures of buildings.

Thermal Degradation and Combustion Performance Comparison of Plywood Based on Inorganic Adhesive and Phenol-Formaldehyde Resin

2017 ◽  
Vol 14 (1) ◽  
pp. 775-779
Author(s):  
Shoulu Yang ◽  
Yiqiang Wu ◽  
Ning Ji ◽  
Yan Qing ◽  
Dan Li ◽  
...  
Keyword(s):  
Phenol Formaldehyde ◽  
Thermo Gravimetric Analysis ◽  
Performance Comparison ◽  
Phenol Formaldehyde Resin ◽  
Formaldehyde Resin ◽  
Gravimetric Analysis ◽  
Thermo Gravimetric ◽  
Total Mass Loss ◽  
Thermal Stability Of ◽  
Made In

The main objective of this work was to study a new inorganic adhesive used for wood-based panel. Inorganic adhesive and its poplar plywood were prepared to investigate their properties. Thermo-gravimetric analysis tests revealed that the total mass loss of inorganic adhesive was 76.24%, which was higher than that of phenol-formaldehyde resin (64.97%). The results showed better thermal stability of inorganic adhesive. For inorganic adhesive plywood, approximately 30% decrease in peak of heat release rate, 62% in total smoke production and 20% in mean CO2 yield, respectively, were seen compared to the control by cone calorimeter analysis. Scanning electron microscopy imaged wider glue line of inorganic adhesives plywood, which was related to the bonding strength of plywood. Thus the inorganic adhesive of fireproofing made in lab could be better used for plywood processing.

Effect of DFA Modification on Thermal Properties of Multifunctional Epoxy/Anhydride Systems

2017 ◽  
Vol 748 ◽  
pp. 35-38
Author(s):  
Ming Ming Yu ◽  
Lin Fang ◽  
Min Yang ◽  
Hong Li ◽  
Mu Su Ren ◽  
...  
Keyword(s):  
Epoxy Resins ◽  
Dynamic Method ◽  
Degradation Kinetics ◽  
Thermo Gravimetric Analysis ◽  
Thermal Degradation Kinetics ◽  
Gravimetric Analysis ◽  
Thermo Gravimetric ◽  
Thermal Stabilities ◽  
Ozawa Model ◽  
Thermal Stability Of

The thermal stabilities of two amine based multifunctional epoxy resins (TGDDE/MNA & TGBAPP/MNA) and two dimer carboxylic acid (DFA) toughened resins (DFA-TGDDE/MNA & DFA-TGBAPP/MNA) were comparatively investigated with the thermo-gravimetric analysis (TG). The TG parameters of the resins indicated that the thermal stability of the resins was increased after the modification. Furthermore, the thermal degradation kinetics was studied with a dynamic method according to Ozawa model, which explained this phenomenon.

scholarly journals Characterization of Lignocellulosic Fibers Reinforced with Poly(vinyl alcohol)

2021 ◽  
Vol 6 (1) ◽  
pp. 6-15
Author(s):  
Manasa V Anand ◽  
◽  
R Ravishankar ◽  
Kiran S Vasist ◽  
Madhu H N ◽  
...  
Keyword(s):  
Environmental Sustainability ◽  
Vinyl Alcohol ◽  
Food Packaging ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
Poly Vinyl Alcohol ◽  
Crystalline Cellulose ◽  
Uniform Dispersion ◽  
The Matrix ◽  
Biocomposite Film

The demands for materials made of plastics are rapidly increasing, especially in food packaging application. Recently, attention has been drawn to the use of bio-reinforced composites in packaging, automotive, medical and construction applications due to increased concern for environmental sustainability. Poly(vinyl alcohol) (PVA) films reinforced with crystals (unbleached) prepared by solution casting method possessed significantly improved properties compared to film reinforced with cellulose (bleached). From the results, PVA films with the addition of 4% (w/w) of crystalline cellulose exhibited best combination of properties. In addition to good mechanical properties, this composite has good water resistance and biodegradability. The water absorption of biocomposite was found to be 22.63%. From X - ray diffraction (XRD) analysis, diffraction peaks of biocomposite was observed at 2θ = 22.4384. From scanning electron microscopy (SEM) analysis it was found that fractures at surfaces of biocomposite film were smooth and even without any porosity and uniform dispersion of jute crystals in the matrix.

scholarly journals White light emitting dysprosium doped lanthanum oxalate single crystals

2021 ◽  
Vol 2070 (1) ◽  
pp. 012097
Author(s):  
S Vandana ◽  
Cyriac Joseph
Keyword(s):  
Single Crystals ◽  
White Light ◽  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
Thermo Gravimetric ◽  
Visible Absorption ◽  
Light Emitting ◽  
X Ray ◽  
Uv Visible ◽  
Thermal Stability Of

Abstract Single crystals of Lanthanum oxalate [La2 (C2O4)3]1OH2O and Dy3+ doped Lanthanum oxalate [La2-xDyx (C2O4)3]10H2O with x=0.1, 0.15, 0.2 were grown by gel method and characterised by X-ray powder diffraction analysis. Thermal stability of sample was investigated by thermo gravimetric analysis. UV-Visible absorption and photo-luminescent studies were also conducted. The emission spectrum on exciting at 271nm and 364 nm were recorded in which Dy3+ ions showed four emission bands at positions 458nm (blue), 478 nm (blue), 572 nm (yellow) and 655 nm (red) corresponding to transitions 4I15/2→ 6H15/2, 4F9/2→ 6H15/2, 4F9/2→ 6H13/2 and 4F9/2→ 6H11/2 respectively. The CIE coordinates, colour purity and CCT values were calculated, and all these parameters show that Dy3+ doped lanthanum oxalate single crystals are suitable candidates for white light emitting applications.

Preparation, Characterization and Properties of Biodegradable GO/PPC Composites

2013 ◽  
Vol 469 ◽  
pp. 112-116
Author(s):  
Xia He ◽  
Ling Ling Wu ◽  
Jia Jun Wang ◽  
Hai Long Liu
Keyword(s):  
Thermal Properties ◽  
Food Packaging ◽  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
Thermo Gravimetric ◽  
Promising Alternative ◽  
Solution Blending ◽  
Blending Method ◽  
Ft Ir ◽  
Poly Propylene

A novel biodegradable and biocompatible composite of Poly (propylene carbonate) (PPC) and graphenes oxide (GO) was prepared by a solution blending method. The chemical structure, thermal properties and microscopic morphologies of the GO/PPC composites were characterized by Fourier transform infrared spectroscopy (FT-IR), thermo gravimetric analysis (TGA) and scanning electron microscopy (SEM). It was shown that the GO/PPC composites with 0.75 wt% GO performed a significant improvement on mechanical properties and thermal properties, as compared with the neat PPC. This composite could become a promising alternative to non-biodegradable for food packaging materials.

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