Effect Of Superabsorbent Polymer Research Articles

Effect of Superabsorbent Polymers on Workability and Hydration Process in Fly Ash Cementitious Composites

AbstractThe effects of three superabsorbent polymers (SAPs) on variations in the cement hydration process were studied by calorimetric measurements and the X-ray scanning technique. It was concluded that the influence of superabsorbent polymers on workability and autogenous shrinkage strongly depends on SAP water absorption/desorption kinetics. Gradual release of additional water stored by a SAP facilitated the formation of a denser and more homogenous cementitious matrix. The addition of fly ash to portland cement had a notable influence on the hydration process and microstructure development in mortars regardless of modifications by the SAP. Characteristic patterns attributed to pozzolanic reactions appeared to be related to the mortar densification measured by the X-ray absorption and quasi-adiabatic calorimetry techniques during the first 48 h.

The effect of Superabsorbent Polymers (SAP) on microstructure and mechanical properties of fly ash cementitious mortars

The paper is focused on microstructure and strength development in fly ash cementitious mortars containing superabsorbent polymers. In order to evaluate the effect of different water absorption/desorption kinetics of SAPs, comprehensive MIP and SEM analysis supplemented by the mechanical properties assessments have been performed. The vast majority of pores created by SAP are ‘ink-bottle’ and/or closed. Gradual release of water stored by SAP facilitates formation of denser, more homogenous and predictable cementitious matrix, further enhanced by the pozzolanic reaction of fly ash with portlandite. Addition of SAP with high water absorption capacity results in an increased compressive strength.

The Effect of Superabsorbent Polymers on the Water Holding Capacity and Water Potential of Karkhe Noor Sandy Soils

Superabsorbent polymers are used in agriculture for the purpose of increasing water use efficiency in arid and semi- arid regions. In this research two kinds of superabsorbent polymers, Super AB A200 and Herbosorb were used on sandy soils of Karkhe Noor river bank near Hamidieh. The effect of 5 concentration levels of 0.3, 0.6, 0.8, 2 and 4 grams per kilogram of soil in 3 replications was studied on the parameters of soil moisture characteristic curve using RETC program and Rosetta database. It was observed that fitting of the data to the RETC model was better compared to Rosetta. Statistical analysis of the research results show that for sandy soils in these experiments there was a significant difference at one percent level for all the polymers used and the control treatment at suctions of 0.3, 1, 3, 5 and 15 bars. On the other hand for the different concentration levels of 4, 2, 0.8, 0.6 and 0.3 g/kg soil, volumetric soil moisture content showed a significant difference at one percent level. Among the superabsorbents used A200 with application rate of 4 g/kg soil resulted in the highest effect. Soil available water for plant use showed an increase compared to the control treatment. It was finally concluded that the application of 4 gram Super AB A200 and Herbosorb per kilogram soil increased soil available water about 350 and 320 percent respectively.

English

This study was conducted with the main purpose to investigate the effect of super absorbent polymer and different levels of irrigation on characteristics of Myrobalan (Prunus cerasifera) seedling. The experiment was laid out in randomized complete design with five level (0.0, 0.5, 1, 2 and 3%) super absorbent polymer and three levels of water irrigation including 4 day (control), 8 and 12 day from germination until two month and each of these levels was repeated ten replication at Khorasan Razavi Natural Resources and Agricultural Research Center. During the experiment, the plants different physicomorpholigic such as plant height, number and surface of the leaf, fresh and dry weight of plant, number of root, root height and diameter of plant were estimated. The results indicated that the effect of interaction between super absorbent and water stress was significant on some of quantity characteristics of P. cerasifera. In all traits, a significant decrease was observed with increase in stress level. The highest plant height, number and surface area of the leaf, fresh and dry weight and diameter of plant was related to irrigation after 4 days with 3% polymer application and the lowest was related to irrigation after 12 days with no application of polymer. The results indicated that using S.A.P controlled of relationship soil, water and plant, decrease water stress.   Key words: Level irrigation, Prunus cerasifera, superabsorbent polymer, water stress.

Effect of Super-Absorbent Polymer as Admixture on the Mechanical Properties of Mortars

Super-absorbent polymer particles (SAPs) were used as a self-curing admixture for mortars. The effect of SAPs on mechanical properties of mortars was investigated. The performance of the mortars with SAPs added by two different ways was tested, which showed that the way of adding dried was more feasible to application. The performance of mortars with different curing methods was also tested. The results showed that SAPs in the mortars played a role of reserving water and the mechanical properties of hardened mortars with SAPs were better than those had no SAPs and exposed to the air, which suggested that incorporating SAPs can be an effective self-curing method.

The Effect of Super-Absorbent Polymer as a Self-Curing Admixture on the Performance of Mortars

Super-absorbent polymer (SAP) was used as a self-curing admixture for cement-based materials. Two types of super-absorbent polymer and effect of super-absorbent polymer on fluidity and mechanical properties of mortars were investigated. The performance of the mortars cured for different ages was tested. The results showed that SAP could play a role of reserving water and reserving water of SAP particles A with an average diameter of 180 mm was more effective than that of SAP particles B with an average diameter of 80 mm, the optimal performance of reserving water was obtained at 0.07 wt.% of SAP particles A; Mechanical properties of hardened mortars with SAP particles A were better than those with SAP particles B, the favorably experiment ratio was 0.05 wt.% of SAP particles A.

Water-saving Effect of Superabsorbent Polymers on Ordos Sandy Soil

Water-saving Effect of Superabsorbent Polymers on Ordos Sandy Soil

Promoting effect of super absorbent polymer on hydrate formation

The effect of super absorbent polymer (SAP) on the formation of tetrahydrofuran (THF) hydrate was studied by the successional cooling method. It was found that THF solution samples with 0.004 wt% and 0.03 wt% of SAP formed THF hydrate completely during the same cooling process. The corresponding induction time was 16–29 min, 14–31 min, respectively, which was obviously shorter than that of THF solution samples without SAP (25–62 min). It indicated that SAP accelerated the formation of THF hydrate. At the same time, the pictures of hydrate formation with and without SAP had been compared. It was found that SAP did not change the morphology of the hydrate. Finally, the mechanism of SAP promoting effect on the formation of THF hydrate was suggested.

Effect of superabsorbent polymers on survival and growth of crop seedlings

Synthetic, superabsorbent polymers are soil conditioners developed to aid plant establishment and growth in drought-prone growing media. The effects of a starch co-polymer and a polyacrylamide co-polymer on the establishment and growth of lettuce and barley were investigated. The crops were grown under limited irrigation on a coarse sand substrate. The interval between field capacity and the onset of wilting was increased by up to three-fold in the presence of polymer. Water use efficiency and dry matter production also responded positively to the presence of both the polymers tested.