scholarly journals Effect of Different Surface-charged Lamellar Materials on Swelling Properties of Nanocomposite Hydrogels

2021 ◽  
Author(s):  
Marcela Pfeifer ◽  
Flávio A. C. Andrade ◽  
Ricardo Bortoletto-Santos ◽  
Fauze A. Aouada ◽  
Caue Ribeiro
Keyword(s):  
Water Absorption ◽  
Anomalous Behavior ◽  
Absorption Capacity ◽  
Water Absorption Capacity ◽  
Swelling Properties ◽  
Ph Variation ◽  
Nanocomposite Hydrogels ◽  
Thermally Activated ◽  
Different Temperatures ◽  
Lamellar Materials

Abstract This study investigated the effect of different surface-charged lamellar materials on the swelling and diffusion properties of synthesized polyacrylamide-methylcellulose hydrogels (HG). Montmorillonite and hydrotalcite thermally activated at two different temperatures (300 and 550 ºC) were incorporated in the preparation of nanocomposite (NC) hydrogels. A series of NC hydrogels were prepared by varying the lamellar material content (1:1, 2:1 and 4:1). The results showed that the HG with hydrotalcite (550 ºC) was strongly dependent on the ionic intensity, and that the swelling degree increased by 50%, 65% and 78% with reducing the hydrotalcite content at (1:1), (2:1) and (4:1), respectively. The water absorption capacity of HG containing montmorillonite or hydrotalcite (300 ºC) was slightly affected when the pH decreased from 7 to 3. However, the pH variation from 7 to 10 increased the water absorption capacity of most HG, except those containing hydrotalcite (550 ºC) at (2:1) and (4:1). The presence of lamellar nanoparticles in hydrogels made the polymer matrix more rigid, and less likely to absorb water. In contrast, HG with hydrotalcite (550 ºC) at (2:1) and (4:1) showed anomalous behavior with an increase in their water absorption capacity. The results support that the developed NC-HG can be suitable candidates for applications as controlled released materials.

Villus-like nanocomposite hydrogels with a super-high water absorption capacity

2020 ◽  
Vol 8 (25) ◽  
pp. 12613-12622
Author(s):  
Xiaosai Hu ◽  
Qiao Wang ◽  
Qing Liu ◽  
Zongjin Li ◽  
Guoxing Sun
Keyword(s):  
Water Absorption ◽  
High Water ◽  
Absorption Capacity ◽  
Water Absorption Capacity ◽  
Nanocomposite Hydrogels ◽  
High Water Absorption

Villi-like structure greatly improved the water absorption capability of super water absorbing hydrogels (SAH).

Study of water absorption capability of swellable starch

2021 ◽  
Vol 9 (16) ◽  
pp. 205-211
Author(s):  
Liubomyr Khomichak ◽  
◽  
Inha Kuznietsova ◽  
Liudmyla Zajchuk ◽  
Mariia Yarmolyuk ◽  
...  
Keyword(s):  
Water Absorption ◽  
Corn Starch ◽  
Absorption Capacity ◽  
Convective Drying ◽  
Solution Temperature ◽  
Water Absorption Capacity ◽  
Priority Task ◽  
Starch Extrusion ◽  
Different Temperatures ◽  
Formed Structure

Usually for the production of swellable starch extrusion treatment or drying on a drum roller dryer are used. The properties of swellable starch with a newly formed structure are evaluated mainly by the water absorption capacity in water under the action of temperature. The ability of swellable starch to thicken, stabilize, bind and enamel various food and non-food products depends on this indicator. The study of the index of water absorption capacity (WAC) of swellable starch obtained by our improved technology based on the use of convective dryer is an urgent and priority task. Research methodology. Control – extruded corn starch. Samples of swellable starch obtained by preparation of starch suspensions of different concentrations of 25, 30, 35 and 40 % were dried under conditions of two-stage convective drying, crushed and sieved. Research results. The obtained samples of swellable starch differ in the value of WAC. It is shown that the WAC of swellable starch affects not only the method of its production but also affects the concentration of starch suspension (SS) from which the samples of swellable starch were made. The obtained value of the approximation coefficient shows that the strongest bond (value - 1) has a sample of swellable starch obtained by convective drying from a concentration of SS 25 %. Conclusions. The WAC of extruded and swellable starch samples obtained by convective drying from different concentrations of SS from 25 to 40 % was investigated. It is shown that at a temperature of 20 °С the lowest value of WAC has swellable starch obtained from 25 % of the concentration of SS and the highest value in 35 % of the concentration of SS. Low strength of the newly formed structure is detected by samples at different temperatures, in particular, extruded starch and a sample obtained from SS 25 % at an aqueous solution temperature of 40-50 °C, a sample obtained from SS 30 % at 60 °C, a sample obtained from SS 35 % at temperature of 40 °C, the sample was obtained from SS 40 % at temperatures of 30 and 50 °C.

Environment friendly qualitatively responsive ethyl cellulose films as smart food packaging

2019 ◽  
Vol 9 (7) ◽  
pp. 792-800
Author(s):  
Neelam Yadav ◽  
Raminder Kaur
Keyword(s):  
Water Absorption ◽  
Ethyl Cellulose ◽  
Food Packaging ◽  
Peak Load ◽  
Absorption Capacity ◽  
Good Mechanical Property ◽  
Water Absorption Capacity ◽  
Ph Variation ◽  
Cellulose Films ◽  
Regular Increase

The present study assessed the applicability of pH indicators in the polymeric films that can be used as smart packaging in the food industries. The pH responsive films using Ethyl cellulose (EC) and azo indicators [i.e., Methyl Orange (MO) and Methyl Red (MR)] have been developed, which have shown remarkable sensitivity towards the pH variation. After activation in different pH range, the colour variation was measured for each film with the CIE Lab methodology. A significant L * [the parameter L * represents the lightness of colours from 0 (dark) to 100 (light), in CIELAB units] variation of EC-MO was seen ranging from 59 (at 0% acid) to 32 (at 60% acid) while for EC-MR, the variation in L * parameter was seen ranging from 89 (at 0% acid) to 32 (at 50% acid). These qualitatively responsive films were further tested for their water absorption capacity and mechanical properties. The water absorption capacity of the EC film incorporated with indicators were observed to be low as compared to the EC-standard film. The incorporation of MO resulted in a regular increase in water absorption capacity range from 34.08–47.11 while the MR incorporated films showed an irregular increase from 41.13–42.13, during a 24 hrs interval. The film with MO also showed a good mechanical property when tested by a micro UTM. The peak load was observed at around 2.7 N. Necking was more observant in the EC film incorporated with MO as compared to other samples, thus showing good plasticity.

The effect of sugar beet fiber addition on the chemical properties of tortilla chips

2012 ◽  
pp. 385-388 ◽  
Author(s):  
Azadeh Saadatmandi ◽  
Mohammad Elahi ◽  
Reza Farhoosh ◽  
Mahdi Karimi
Keyword(s):  
Sugar Beet ◽  
Water Absorption ◽  
Protein Content ◽  
Chemical Properties ◽  
Absorption Capacity ◽  
Ash Content ◽  
Oil Absorption ◽  
Water Absorption Capacity ◽  
Overall Acceptability ◽  
Tortilla Chips

The incorporation of sugar beet fiber (0–5%) to tortilla chips and the effects on the chemical and sensory properties were studied. Addition of sugar beet fiber (SBF) led to an increasing of water absorption capacity, ash content and darkness while lowering the protein content and oil absorption. Sensory evaluation showed that the overall acceptability of tortilla chips reduces if adding more than 2% SBF.

scholarly journals Water Absorption Capacity Determines the Functionality of Vital Gluten Related to Specific Bread Volume

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 228
Author(s):  
Marina Schopf ◽  
Katharina Anne Scherf
Keyword(s):  
Water Absorption ◽  
Water Content ◽  
Wheat Flour ◽  
Specific Volume ◽  
Disulfide Bonds ◽  
Protein Composition ◽  
Absorption Capacity ◽  
Water Absorption Capacity ◽  
Water Addition ◽  
Wheat Flours

Vital gluten is often used in baking to supplement weak wheat flours and improve their baking quality. Even with the same recipe, variable final bread volumes are common, because the functionality differs between vital gluten samples also from the same manufacturer. To understand why, the protein composition of ten vital gluten samples was investigated as well as their performance in a microbaking test depending on the water content in the dough. The gluten content and composition as well the content of free thiols and disulfide bonds of the samples were similar and not related to the specific bread volumes obtained using two dough systems, one based on a baking mixture and one based on a weak wheat flour. Variations of water addition showed that an optimal specific volume of 1.74–2.38 mL/g (baking mixture) and 4.25–5.49 mL/g (weak wheat flour) was reached for each vital gluten sample depending on its specific water absorption capacity.

Effect on Vulcanized Rubber Compounds of Immersion in Boiling Water

1931 ◽  
Vol 4 (3) ◽  
pp. 426-436
Author(s):  
K. J. Soule
Keyword(s):  
Water Absorption ◽  
Room Temperature ◽  
Anomalous Behavior ◽  
Boiling Water ◽  
Vulcanized Rubber ◽  
Rubber Compounds ◽  
Different Temperatures ◽  
Actual Change

Abstract Further work is very desirable on the effect of different accelerators, antioxidants, and fluxes. It is possible that their study will throw more light on the mechanism of the swelling phenomena, and also help to explain the anomalous behavior of some of the fillers tested. It would also seem to be worth while to study the action of a few selected stocks in water, at several temperatures between room temperature and 100° C., to determine if the water absorption and swelling merely increase with rising temperatures, or whether there might be an actual change in behavior at different temperatures.

Comparison of Bio and Eco-technologies with Chemical Methods for Pre-treatment of Flax Fibers: Impact on Fiber Properties

2014 ◽  
Vol 9 (4) ◽  
pp. 155892501400900 ◽  
Author(s):  
Sabela Camano ◽  
Nemeshwaree Behary ◽  
Philippe Vroman ◽  
Christine Campagne
Keyword(s):  
Water Absorption ◽  
Fiber Bundle ◽  
Glass Fibers ◽  
Fiber Surface ◽  
Pectate Lyase ◽  
High Water ◽  
Absorption Capacity ◽  
Water Absorption Capacity ◽  
Flax Fibers ◽  
The Impact

Flax fibers, available as fiber bundles, are commonly used as fiber reinforcement in composite materials as a substitute for glass fibers. Pre-treatments are often necessary for improving fiber-resin adhesion, and also to facilitate fiber elementarization, and to improve fiber ability to be implemented in mechanical processes limiting fiber damages. This paper focuses on the impact of biotechnologies (effect of 2 different enzymes: a pectate lyase and a laccase) and of an ecotechnology (ultrasound with ethanol), compared to classical chemical pre-treatments (using aqueous NaOH and ammonia) on the final flax fiber bundle properties, before and after a carding process. Fiber surface properties (wettability and/or zeta potential values), fiber elementarization and mechanical properties vary with the type of treatment (chemical nature of product and conditions used). Fibers elementarised using pectate lyase and ultrasound/ethanol have a hydrophilic surface and a high water absorption capacity, and are also of highest quality in terms of increased fineness. Treatment with NaOH yields the poorest fiber bundle tenacity. Laccase enzyme yields long thick hydrophobic fibers having very low water absorption capacity, and the most neutral surface charge. Properties of flax fibers can be easily monitored using different pre-treatments resulting in fibers which would be suited for various final applications.

scholarly journals Experimental study on water level and absorption capacity in a radial well flow in a loess area

2018 ◽  
Vol 19 (5) ◽  
pp. 1313-1321
Author(s):  
Xuezhen Zhang ◽  
Aidi Huo ◽  
Jucui Wang
Keyword(s):  
Unsteady Flow ◽  
Water Absorption ◽  
Water Level ◽  
Steady Flow ◽  
Flow Injection ◽  
Absorption Capacity ◽  
Water Absorption Capacity ◽  
Analysis Method ◽  
Semi Empirical ◽  
Radial Well

Abstract In this paper, the theoretical basis for flow calculation in an injection well was discussed. It proposed that the flow rate of an injection well could be calculated referring to pumping theory and method. A mathematical model of the rising curve of water level around a radial well was established and the equation for calculating the rising curve was given. The calculation equations selected for the water absorption capacity of injection wells were explained and examples were verified and compared. The results indicated that, under the same injection conditions, the water level value calculated by the analysis method was slightly larger, but the error between the analysis method and the semi-theoretical and semi-empirical methods was small. In the processes of steady flow injection and unsteady flow injection, there was a small difference of water absorption capacity, and the former was slightly larger. The measured values of water absorption capacity were only about one-third of the calculated values based on pumping theory. Overall, the analytical solution method for predicting the rising curve of water level has priority in well injection. The semi-theoretical and semi-empirical equation for calculating water absorption capacity sifted first has priority in steady flow injection, the equation sifted second has priority in unsteady flow injection.

scholarly journals Formation of porous ceramics using cullet and biological waste of water purification

2011 ◽  
Vol 43 (1) ◽  
pp. 81-94 ◽  
Author(s):  
M. Vlasova ◽  
I. Rosales ◽  
M. Kakazey ◽  
Parra Parra ◽  
R. Guardian
Keyword(s):  
Mechanical Properties ◽  
Water Absorption ◽  
Water Purification ◽  
Sintering Temperature ◽  
Porous Ceramics ◽  
Absorption Capacity ◽  
Water Absorption Capacity ◽  
Red Clay ◽  
Temperature Range

Porous ceramics (bricks) was obtained using red clay, milled fusible cullet, and biowaste in the temperature range 950-1000?C. The high content of water in biowaste eliminates the necessity of introducing water in soft mud forming of bricks. The porosity, water absorption capacity, and mechanical properties of the prepared ceramics depend on content of milled cullet and sintering temperature.

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