scholarly journals One-Step Quaternization/Hydroxypropylsulfonation to Improve Paste Stability, Adhesion, and Film Properties of Oxidized Starch

Polymers ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1110 ◽  
Author(s):  
Wei Li ◽  
Zhenzhen Xu ◽  
Zongqian Wang ◽  
Jian Xing
Keyword(s):  
Tensile Strength ◽  
Degree Of Crystallinity ◽  
Trimethylammonium Chloride ◽  
Film Properties ◽  
Moisture Regain ◽  
Breaking Elongation ◽  
End Use ◽  
Paste Viscosity ◽  
The Stability ◽  
Viscosity Stability

To investigate the influences of quaternization/hydroxypropylsulfonation on viscosity stability, adhesion to fibers and film properties of oxidized tapioca starch (OTS) for ameliorating its end-use ability in applications such as warp-sizing and paper-making, a series of quaternized and hydroxypropylsulfonated OTS (QHOTS) samples were synthesized by simultaneous quaternization and hydroxypropylsulfonation of OTS with N-(3-chloro-2-hydroxypropyl) trimethylammonium chloride (CHPTAC) and 3-chloro-2-hydroxy-1-propanesulfonic acid sodium salt (CHPS-Na). The QHOTS granules were characterized by Fourier transform infra-red spectroscopic and scanning electron microscope techniques. Apparent viscosity and viscosity stability were determined, and adhesion was evaluated by measuring the bonding force of starch to the fibers. Film properties were also estimated in terms of tensile strength, breaking elongation, bending endurance, degree of crystallinity, and moisture regain. It was showed that quaternization/hydroxypropylsulfonation was capable of obviously improving viscosity stability of gelatinized OTS paste, enhancing bonding forces of OTS to cotton and polylactic acid (PLA) fibers, increasing breaking elongation, bending endurance and moisture regain of film and decreasing its tensile strength and degree of crystallinity, thereby obviously stabilizing paste viscosity, improving adhesion to fibers and lessening film brittleness. Increasing the level of quaternization/hydroxypropylsulfonation favored improvement in the stability, enhancement in adhesion and decrease in brittleness. The QHOTS showed potential in the applications of cotton and PLA sizing.

scholarly journals Investigation on the Synthesis Process of Bromoisobutyryl Esterified Starch and Its Sizing Properties: Viscosity Stability, Adhesion and Film Properties

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1936
Author(s):  
Wei Li ◽  
Jie Wu ◽  
Zhengqiao Zhang ◽  
Lanjuan Wu ◽  
Yuhao Lu
Keyword(s):  
Reaction Time ◽  
Polylactic Acid ◽  
Process Parameters ◽  
Reaction Temperature ◽  
Graft Copolymers ◽  
Degree Of Crystallinity ◽  
Synthesis Process ◽  
Film Properties ◽  
Breaking Elongation ◽  
Viscosity Stability

To confirm the suitable synthesis process parameters of preparing bromoisobutyryl esterified starch (BBES), the influences of the synthesis process parameters—amount of 2-bromoisobutyryl bromide (BIBB), amount of catalyst (DMAP), reaction temperature and reaction time—upon the degree of substitution (DS) were investigated. Then, to produce a positive effect on the properties of graft copolymers of BBES prepared in the near future, a series of BBES samples were successfully prepared, and their sizing properties, such as apparent viscosity and viscosity stability, adhesion, and film properties, were examined. The BBES granules were characterized by Fourier transform infra-red spectroscopy and scanning electron microscopy. The adhesion was examined by determining the bonding forces of the sized polylactic acid (PLA) and polyester roving. The film properties were investigated in terms of tensile strength, breaking elongation, degree of crystallinity, and cross-section analysis. The results showed that a suitable synthesis process of BBES was: reaction time of 24 h, reaction temperature of 40 °C, and 0.23 in the molar ratio of 4-dimethylaminopyridine to 2-bromoisobutyryl bromide. The bromoisobutyryl esterification played the important roles in the properties of the starch, such as paste stabilities of above 85% for satisfying the requirement in the stability for sizing, improvement of the adhesion to polylactic acid and polyester fibers, and reduction of film brittleness. With rising DS, bonding forces of BBES to the fibers increased and then decreased. BBES (DS = 0.016) had the highest force and breaking elongation of the film. Considering the experimental results, BBES (DS = 0.016) showed potential in the PLA and polyester sizing, and will not lead to a negative influence on the properties of graft copolymers of BBES.

Preparation and Characterization of β-glucosidase Films for Stabilization and Handling in Dry Configurations

2020 ◽  
Vol 21 (8) ◽  
pp. 741-747
Author(s):  
Liguang Zhang ◽  
Yanan Shen ◽  
Wenjing Lu ◽  
Lengqiu Guo ◽  
Min Xiang ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Protein Function ◽  
Protein Stabilization ◽  
Functional Protein ◽  
Elongation At Break ◽  
Gelatin Films ◽  
The Stability ◽  
And Function ◽  
General Method

Background: Although the stability of proteins is of significance to maintain protein function for therapeutical applications, this remains a challenge. Herein, a general method of preserving protein stability and function was developed using gelatin films. Method: Enzymes immobilized onto films composed of gelatin and Ethylene Glycol (EG) were developed to study their ability to stabilize proteins. As a model functional protein, β-glucosidase was selected. The tensile properties, microstructure, and crystallization behavior of the gelatin films were assessed. Result: Our results indicated that film configurations can preserve the activity of β-glucosidase under rigorous conditions (75% relative humidity and 37°C for 47 days). In both control films and films containing 1.8 % β-glucosidase, tensile strength increased with increased EG content, whilst the elongation at break increased initially, then decreased over time. The presence of β-glucosidase had a negligible influence on tensile strength and elongation at break. Scanning electron-microscopy (SEM) revealed that with increasing EG content or decreasing enzyme concentrations, a denser microstructure was observed. Conclusion: In conclusion, the dry film is a promising candidate to maintain protein stabilization and handling. The configuration is convenient and cheap, and thus applicable to protein storage and transportation processes in the future.

scholarly journals The Influence of Starch Origin on the Properties of Starch Films: Packaging Performance

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1146
Author(s):  
Zuzanna Żołek-Tryznowska ◽  
Alicja Kałuża
Keyword(s):  
Tensile Strength ◽  
Free Energy ◽  
Surface Free Energy ◽  
Food Packaging ◽  
Energy Surface ◽  
Free Energy Surface ◽  
Casting Method ◽  
Starch Solution ◽  
Film Properties ◽  
Starch Films

Starch films can be used as materials for food packaging purposes. The goal of this study is to compare how the starch origin influence the selected starch film properties. The films were made from various starches such as that from maize, potato, oat, rice, and tapioca using 50%w of glycerine as a plasticizer. The obtained starch-based films were made using the well-known casting method from a starch solution in water. The properties of the films that were evaluated were tensile strength, water vapour transition rate, moisture content, wettability, and their surface free energy. Surface free energy (SFE) and its polar and dispersive components were calculated using the Owens-Wendt-Rabel-Kaelbe approach. The values of SFE in the range of 51.64 to 70.81 mJ∙m−2 for the oat starch-based film and the maize starch-based film. The films revealed worse mechanical properties than those of conventional plastics for packaging purposes. The results indicated that the poorest tensile strength was exhibited by the starch-based films made from oat (0.36 MPa) and tapioca (0.78 MPa) and the greatest tensile strength (1.49 MPa) from potato.

scholarly journals Fabrication and Characterization of Electrospun Polycaprolactone Blended with Chitosan-Gelatin Complex Nanofibrous Mats

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Yongfang Qian ◽  
Zhen Zhang ◽  
Laijiu Zheng ◽  
Ruoyuan Song ◽  
Yuping Zhao
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Weight Ratio ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
Tissue Engineering Scaffolds ◽  
Elongation At Break ◽  
Nanofibrous Scaffolds ◽  
Two Peaks

Design and fabrication of nanofibrous scaffolds should mimic the native extracellular matrix. This study is aimed at investigating electrospinning of polycaprolactone (PCL) blended with chitosan-gelatin complex. The morphologies were observed from scanning electron microscope. As-spun blended mats had thinner fibers than pure PCL. X-ray diffraction was used to analyze the degree of crystallinity. The intensity at two peaks at 2θof 21° and 23.5° gradually decreased with the percentage of chitosan-gelatin complex increasing. Moreover, incorporation of the complex could obviously improve the hydrophilicity of as-spun blended mats. Mechanical properties of as-spun nanofibrous mats were also tested. The elongation at break of fibrous mats increased with the PCL content increasing and the ultimate tensile strength varied with different weight ratios. The as-spun mats had higher tensile strength when the weight ratio of PCL to CS-Gel was 75/25 compared to pure PCL. Both as-spun PCL scaffolds and PCL/CS-Gel scaffolds supported the proliferation of porcine iliac endothelial cells, and PCL/CS-Gel had better cell viability than pure PCL. Therefore, electrospun PCL/Chitosan-gelatin nanofibrous mats with weight ratio of 75/25 have better hydrophilicity mechanical properties, and cell proliferation and thus would be a promising candidate for tissue engineering scaffolds.

scholarly journals Thermal Properties and Non-Isothermal Crystallization Kinetics of Poly (δ-Valerolactone) and Poly (δ-Valerolactone)/Titanium Dioxide Nanocomposites

Crystals ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 452 ◽  
Author(s):  
Waseem Saeed ◽  
Abdel-Basit Al-Odayni ◽  
Abdulaziz Alghamdi ◽  
Ali Alrahlah ◽  
Taieb Aouak
Keyword(s):  
Titanium Dioxide ◽  
Crystallization Kinetics ◽  
Isothermal Crystallization ◽  
Three Dimensional ◽  
Degree Of Crystallinity ◽  
Simultaneous Occurrence ◽  
Scanning Calorimetry ◽  
Isothermal Crystallization Kinetics ◽  
The Stability ◽  
Kinetics Of

New poly (δ-valerolactone)/titanium dioxide (PDVL/TiO2) nanocomposites with different TiO2 nanoparticle loadings were prepared by the solvent-casting method and characterized by Fourier transform infra-red, differential scanning calorimetry, X-ray diffraction and scanning electron microscopy, and thermogravimetry analyses. The results obtained reveal good dispersion of TiO2 nanoparticles in the polymer matrix and non-formation of new crystalline structures indicating the stability of the crystallinity of TiO2 in the composite. A significant increase in the degree of crystallinity was observed with increasing TiO2 content. The non-isothermal crystallization kinetics of the PDVL/TiO2 system indicate that the crystallization process involves the simultaneous occurrence of two- and three-dimensional spherulitic growths. The thermal degradation analysis of this nanocomposite reveals a significant improvement in the thermal stability with increasing TiO2 loading.

scholarly journals Study of Mechanical Behavior and Microstructure for Low-Hardness P92 Steel

2021 ◽  
Vol 2101 (1) ◽  
pp. 012074
Author(s):  
Weixin Yu ◽  
Zhen Dai ◽  
Jifeng Zhao ◽  
Lulu Fang ◽  
Yiwen Zhang
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Tensile Strength ◽  
Maximum Size ◽  
Rapid Decrease ◽  
Laves Phases ◽  
P92 Steel ◽  
A Chain ◽  
The Stability ◽  
Evolution Of Microstructure

Abstract The strength of P92 steel (tensile strength, specified plastic elongation strength) will decrease after its hardness is reduced, ferrite and carbides forming the structure. Carbides of grain size 5-6 are precipitated in the grains and grain boundaries. The martensite lath shape has completely disappeared. M23C6 carbide coarsened obviously, with a maximum size of about 500nm; The Laves phase is also aggregated and coarsened, connecting in a chain shape with a maximum size of more than 500nm. Evolution of microstructure, namely the obvious coarsening of M23C6 carbides and the aggregation and connection of Laves phases in a chain shape, are the main causes for rapid decrease in the stability of the material substructure and evident decline in mechanical properties and hardness. In addition, the MX phase did not change significantly, hardly affecting the hardness reduction of P92 steel.

Natural cellulosic fiber from Cordyline Australis leaves for textile application: extraction and characterization

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Atin Sumihartati ◽  
Wiah Wardiningsih ◽  
Naelly Al Kautsar ◽  
Muhammad Permana ◽  
Samuel Pradana ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Friction Coefficient ◽  
Average Length ◽  
Natural Fibers ◽  
Longitudinal Section ◽  
Raw Material ◽  
Scientific Article ◽  
Cross Sectional ◽  
Moisture Regain ◽  
Content Type

Purpose The purpose of this study is to explore the potential of Cordyline Australis fibers as an alternate raw material for textile. Design/methodology/approach The water retting method was used to extract the fiber. Cordyline Australis fibers were characterized in terms of the morphology of fibers (fiber cross-sectional and longitudinal), fiber chemical functional groups, tensile strength and elongation, fineness, fiber length, moisture regain and friction coefficient. Findings Cordyline Australis fiber strands consist of several individual fibers. At the longitudinal section, the fiber cells appeared as long cylindrical tubes with a rough surface. The cross-section of the Cordyline Australis fibers was irregular but some were oval. The key components in the fibers were cellulose, hemicellulose and lignin. The tensile strength of the fiber per bundle was 2.5 gf/den. The elongation of fibers was 13.15%. The fineness of fiber was 8.35 Tex. The average length of the fibers was 54.72 cm. Moisture Regain for fiber was 8.59%. The friction coefficient of fibers was 0.16. The properties of the fiber showed that the Cordyline Australis fiber has the potential to be produced into yarn. Originality/value To the best of the author's knowledge, there is no scientific article focused on the Cordyline Australis fibers. Natural fibers from the leaves of the Cordyline Australis plant could be used as an alternate material for textile.

Advances in measuring mechanical properties of soil in relation to soil health

2021 ◽  
pp. 215-240
Author(s):  
Muhammad Naveed ◽  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Soil Health ◽  
Indentation Test ◽  
Mechanical Tests ◽  
Confined Compression ◽  
Microstructural Stability ◽  
Rigorous Testing ◽  
The Stability ◽  
Properties Of Soil

Although mechanical properties of soil are fast and easy to measure, they have not been used as indicators of soil health apart from cone penetration resistance. The confined compression test is traditionally used for the prediction of soil compaction risks. Other mechanical tests such as soil rheometry, miniature indentation test, and tensile strength are used for assessing the impact of certain amendments on the stability of the soil. Rheological techniques are appropriate to investigate microstructural stability of soil on a particle-particle scale. Miniature indentation test is very useful to perform when mechanical properties of soil are required to measure at the mm scale. Measurement of the tensile strength of soil has an advantage as it eliminates the effect of water content. There is clearly a need for more practical and rigorous testing on comparing different mechanical properties of the soil to test how they perform relative to each other.

Development of Alginate Based Active Films Containing Turmeric Essential Oil

2020 ◽  
Vol 861 ◽  
pp. 378-382
Author(s):  
Sophoan Phal ◽  
Muhammad Rafiullah Khan ◽  
Pattarin Leelaphiwat ◽  
Vanee Chonhenchob
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Tensile Strength ◽  
Water Vapor ◽  
Essential Oil ◽  
Sem Analysis ◽  
Film Properties ◽  
Elongation At Break ◽  
Control Film ◽  
Scanning Electron

Sodium alginate based films containing turmeric oil (TEO) at different concentrations (1, 2 and 3%) were developed. The film with no TEO was used as control. Incorporation of TEO had the effects on the film properties. With increasing TEO concentrations, thickness, elongation at break, permeability of oxygen and water vapor of the films significantly (p ≤ 0.05) increased. Whereas moisture content, tensile strength and modulus of elasticity significantly (p ≤ 0.05) decreased. Scanning electron microscopy (SEM) analysis showed more numerous pores and rougher surface of the antifungal films than the control film.

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