Choice of Super-Absorbent Polymer Hydrogel for Cement Systems

2019 ◽  
pp. 64-70
Keyword(s):  
High Performance ◽  
Cement Composite ◽  
Superabsorbent Polymer ◽  
Super Absorbent Polymer ◽  
Nmr Relaxometry ◽  
Rheological Method ◽  
Acrylic Acids ◽  
Absorbent Polymer ◽  
The Impact ◽  
Non Destructive

The article deals with the control over the structure formation processes of cement systems through the introduction of superabsorbent polymer additives in the composition. The formation of thin polyacrylic films due to delayed polymerization of acrylic acids in aqueous solution in the cement composite structure will provide the hardening Portland cement with water reserve for hydration without loss of mobility of the mixture contributing to the reduction of shrinkage deformations and obtaining a composite with high performance properties. It is shown that for the selection of superabsorbent polymer for cement systems it is advisable to use both the rheological method and NMR relaxometry. An obvious advantage of the NMR method is the non-destructive nature of the impact on the material which makes it possible to more reliably determine the structural-kinetic parameters and analyze the features of the structure transformation over time. It is established that such an indicator as the period of viability can be used to assess the features of the structuring of acrylate super-absorbent polymers when selecting optimal concentrations of its components. Experimental and statistical models describing the dependence of the depth of structuring and the period of viability on the amount of the catalyst and the polymer part of the super-absorbent polymer are obtained.

Study on Preparation for Super Absorbent Polymer Using Cotton Waste

2012 ◽  
Vol 602-604 ◽  
pp. 704-707
Author(s):  
Lei Tan ◽  
Zheng Qin Liu ◽  
Yang Yang Liu
Keyword(s):  
High Viscosity ◽  
Polymerization Temperature ◽  
Water Absorbency ◽  
Mass Ratio ◽  
Optimum Conditions ◽  
Super Absorbent Polymer ◽  
Cotton Waste ◽  
Absorbent Polymer ◽  
The Impact ◽  
Temperature Time

For the purpose of recycling of cotton waste cuttings and exploring the prospect of preparation for super absorbent polymer (SAP), the high viscosity carboxymethyl cellulose (CMC) was made from cotton waste first and then the SAP was synthesized by grafting acrylic acid (AA) onto the CMC with the potassium persulfate being as initiator, N, N'-methylene bis acrylamide as crosslinker. The impact of polymerization temperature, time, initiator dosage, AA concentration, crosslinker dosage, and neutralization degree on water absorbency of SAP was studied. The optimum conditions are mass ratio of AA and CMC 7.11 g/g, initiator dosage 0.03 g/g CMC, crosslinker dosage 0.2 g/100g AA, neutralization degree 80% and polymerization time 1.5 h at 70°C of the polymerization temperature. The water retention of the polymer is good and the water absorbency reaches up to 702.5 g/g.

The Study on Preparation of Kaolin-Acrylic Super Absorbent Polymer and its Internal Curing Effect in the Hydration Procedure of Cement Materials

2012 ◽  
Vol 622-623 ◽  
pp. 276-279
Author(s):  
Yan Shuai Wang ◽  
Xiang Ping Xian ◽  
Feng Xing ◽  
Bi Qin Dong
Keyword(s):  
Cement Paste ◽  
Water Adsorption ◽  
Early Stage ◽  
Internal Curing ◽  
Superabsorbent Polymer ◽  
Sodium Persulfate ◽  
Compressive Properties ◽  
Super Absorbent Polymer ◽  
Natural Mineral ◽  
Absorbent Polymer

In this paper, a new kind of superabsorbent polymer (SAP) is designed and prepared. Using sodium persulfate as initiator and N,N’-methylene bisacrylamide as Crosslinker, monomer of acrylic acid can be grafted into the skeleton of natural mineral kaolin with the method of microwave irradiation. The performance of water adsorption for SAP is tested in saturated Ca(OH)2 solution. Also, the internal curing effect of SAP to hydration procedure of cement paste is studied. The result shows that the compressive properties and flexural strength of cement paste specimens in early stage have significant improvement in contrast to those without superabsorbent polymer or excessive or a small amount of superabsorbent polymer, when superabsorbent polymer is accounted for 0.3% to 0.5% of the total cement.

scholarly journals Synergetic effect of a super-absorbent polymer and a calcium nitrite corrosion inhibitor in high performance concrete durability

2020 ◽  
Vol 10 (2) ◽  
pp. 206-218
Author(s):  
Alejandro Duran Herrera ◽  
Jennifer Anette Canul-Polanco ◽  
Rogelio Dávila-Pompermaye ◽  
Lucio Guillermo López-Yépez ◽  
Pedro Leobardo Valdez-Tamez
Keyword(s):  
Electrical Resistivity ◽  
Corrosion Inhibitor ◽  
High Performance ◽  
High Performance Concrete ◽  
Synergetic Effect ◽  
Autogenous Shrinkage ◽  
Concrete Durability ◽  
Super Absorbent Polymer ◽  
Calcium Nitrite ◽  
Absorbent Polymer

In this research, the synergetic effect of a super-absorbent polymer in combination with a calcium nitrite corrosion inhibitor were evaluated as a combined technology to improve concrete durability in High Performance Concrete. For this purpose, Portland cement mortars with a water/cement ratio of 0.4 and a substitution of 9.5% of cement by silica fume were produced. The effect of this technologies was evaluated by measuring the following parameters: autogenous and drying shrinkage, surface electrical resistivity and the non-steady-state chloride migration coefficient. The results indicate that the synergistic effect of SAP + CNI improves autogenous shrinkage and surface electrical resistivity.

Dietary Vitamin and Stability of Oral Anticoagulation: Proposal of a Diet with Constant Vitamin K1 Content

1997 ◽  
Vol 77 (03) ◽  
pp. 504-509 ◽  
Author(s):  
Sarah L Booth ◽  
Jacqueline M Charnley ◽  
James A Sadowski ◽  
Edward Saltzman ◽  
Edwin G Bovill ◽  
...  
Keyword(s):  
Dietary Intake ◽  
Vitamin K ◽  
High Performance ◽  
Case Reports ◽  
Food Composition ◽  
Dietary Guidelines ◽  
Dietary Vitamin ◽  
Vitamin K1 ◽  
The Stability ◽  
The Impact

SummaryCase reports cited in Medline or Biological Abstracts (1966-1996) were reviewed to evaluate the impact of vitamin K1 dietary intake on the stability of anticoagulant control in patients using coumarin derivatives. Reported nutrient-drug interactions cannot always be explained by the vitamin K1 content of the food items. However, metabolic data indicate that a consistent dietary intake of vitamin K is important to attain a daily equilibrium in vitamin K status. We report a diet that provides a stable intake of vitamin K1, equivalent to the current U.S. Recommended Dietary Allowance, using food composition data derived from high-performance liquid chromatography. Inconsistencies in the published literature indicate that prospective clinical studies should be undertaken to clarify the putative dietary vitamin K1-coumarin interaction. The dietary guidelines reported here may be used in such studies.

Alpha Tocopherol Loaded in Liposome: Preparation, Optimization, Characterization and Sperm Motility Protection

2020 ◽  
Vol 10 (3) ◽  
pp. 228-236 ◽  
Author(s):  
Lamia Taouzinet ◽  
Sofiane Fatmi ◽  
Allaeddine Khellouf ◽  
Mohamed Skiba ◽  
Mokrane Iguer-ouada
Keyword(s):  
Vitamin E ◽  
Sperm Motility ◽  
High Performance ◽  
Positive Impact ◽  
Alpha Tocopherol ◽  
Ethanol Injection ◽  
Liposome Preparation ◽  
Liposome Size ◽  
Optimum Solution ◽  
The Impact

Background: Alpha-tocopherol is a potent antioxidant involved in sperm protection particularly during cryopreservation. However, its poor solubility limits the optimal protection in aqueous solutions. Objective: The aim of this study was to enhance the solubility of α-tocopherol by the use of liposomes. Methods: The experimental approach consisted to load vitamin E in liposomes prepared by ethanol injection method and the optimization carried out by an experimental design. The optimum solution was characterized by high performance liquid chromatography and scanning electron microscope. Finely, the impact on sperm motility protection was studied by the freezing technic of bovine sperm. Results: The optimum solution was obtained when using 10.9 mg/ml of phospholipids, 1.7 mg/ml of cholesterol and 2 mg/ml of vitamin E. The liposome size was 99.86 nm, providing 78.47% of loaded efficiency. The results showed also a significant positive impact on sperm motility after hours of preservation. Conclusion: In conclusion, the current results showed the interest of liposome preparation as an alternative to enhance vitamin E solubility and to protect spermatozoa during cryopreservation.

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