Papers by Keyword: Superabsorbent Polymer

Abstract: The graft polymerization of acrylic acid by varying the amount of cross-linker in ranging of 0.001 g to 0.05 g was investigated. The effect of cross-linker in synthesized superabsorbent polymers (SAP) was identified in terms of water absorbency responses by keeping the values of monomer and initiator. The implementation of SAP in agriculture could develop plant growth, enhancing water retention capacity in soils which can reducing dewatering system and improved the efficiency of soil condition so higher yield of product can be obtained particularly in arid regions. The SAPs were synthesized by graft polymerization using acrylic acid (AA) as monomer, N,N’-methylene bisacrylamide (MBA) as cross-linker and ammonium persulfate (APS) as initiator. The optimum water absorbency of synthesize SAP was defined using tea-bag method in deionize water. The structures of synthesize SAP was characterized by Fourier Transform Infrared Spectroscopy (FTIR) and morphologies of synthesize SAP was examined by Scanning Electron Microscope (SEM) testing. From the result, it was obvious showed that water absorbency will decreased as the increased of concentration of cross-linker which is MBA in synthesize SAP. The best value content of MBA was 0.01 g which achieved the highest water absorbency response which is 170 g water/g sample. In conclusion, SAP has hydrophilic structure of which renders them capable for holding a large amount of water which can help to retain nutrients and absorb water in soil with various applications for plant growth and soil condition which will be useful especially in agriculture field.

Abstract: The article is devoted to compare the properties of super absorbent polymers useful in concrete. The idea of using super absorbent polymers (SAP) is the replacement of the treatment water in concrete structures. The properties are compared in terms of change of the volume and the ability of spilling of cement mixture which contains SAP.

Abstract: Superabsorbent polymer (SAP) has been widely used in many application such as in hygiene products, agriculture and also horticulture, wastewater treatment and others. The absorbency and degradability of SAP can be enhanced by utilization of carbon filler. In this research, SAP with carbon filler has been synthesized using graft polymerization method. Acrylic acid (AA) used as monomer, N, N-methylbisacrylamide (MBA) used as crosslinking agent, ammonium persulphate (APS) as initiator and different size of natural carbon filler used as filler. Water absorbency test showed that SAP with 500 μm carbon filler has highest degree of swelling while SAP with 125 μm and 71 μm carbon filler has degree of swelling lower than degree of swelling of control hydrogel. Scanning electron microscopic (SEM) image showed 500 μm carbon filler has better surface morphology and alignment to make interfacial contact with hydrogel besides buil excellent capillary effect to absorb and store more water. In conclusion, smaller in particle size of filler will decrease the degree of swelling of SAP.

Abstract: A novel polyacrylic acid /xanthan gum/bentonite superabsorbent polymer (SAP) was prepared through chemical crosslinking by a polymerization technique in a complete aqueous environment. This SAP was fabricated effectively by dispersing xanthan gum (XG) and bentonite in a monomeric solution, using N,N’-methylenebisacrylamide as crosslinker and ammonium persulfate as initiator. Fourier transform infrared (FTIR) spectral analysis showed that graft copolymerization reaction took place between acrylic acid (AA), XG and bentonite. The optimal process conditions of preparing SAP were investigated. Results showed that the relevant SAP had maximal salt-water absorption (98g/g) when mass ratio of m (bentonite):m (AA) was 5:1, m (ammonium persulfate):m (AA) was 1.75×10^-4, m (N,N’-methylenebisacrylamide):m (AA) was 3×10^-4, m (XG) :m (AA) was 1:5, the neutralization degree of AA was 75%. Bentonite can not only effectively increase water absorbency, but also improve water retention ability.

Abstract: By microwave method, a superabsorbent function composite material was prepared by grafting sodium acrylate onto straw flour using potassium persalfate (K₂S₂O₈) and N, N'-methylene bis acrylamide as an initiator and crosslinker, respectively. The effect of various preparation conditions on its water absorbency was investigated. When the straw flour content was 6%, the acrylic acid content was 20.0g, the amount of initiator was 0.4%, the neutralization degree of monomer was 80%, the reaction temperature was 70°C and the amount of crosslinker was 0.05%, the materials absorbency was 1360 times in distilled water and 152 times in 0.9% salt-water at ambient temperature. It had also high water retention. The analyses of SEM indicate that sodium acrylate is grafted on the polysaccharides of straw flour.

Abstract: A novel superabsorbent composite has been prepared via aqueous solution polymerization of acrylic acid (AA) in the presence of PVP modified bentonite powder using N,N-methylenebisacrylamide (MBA) as a crosslinker and potassium persulfate (KPS) as an initiator. The amount of PVP modified bentonite in the superabsorbent affected on the ultimate water absorbency was optimized, and the swelling kinetics and water retention ability were systematically investigated. The composite structure was determined by Fourier transform infrared (FTIR) spectroscopy, Thermogravimetric Analyzer (TG) and the scanning electron microscopy (SEM). The results indicate that the superabsorbents with PVP modified bentonite own superior water-swelling capability and water retention ability.

Abstract: In order to research the better water absorption characteristic of superabsorbent polymer based on acrylic acid grafted with xanthan gum (XG), the different clay of montmorillonite (MMT) and attapulgite (AC) was used to mix with the material respectively. By introducing montmorillonite or attapulgite to the superabsorbent polymer, the maximum water absorbency was enhanced obviously. The two kinds of superabsorbent polymers of XG-g-PAA / MMT and XG-g-PAA / AC were synthesized by free-radical graft polymerization in aqueous solution using potassium persulfate as a free radical initiator and methylenebisacrylamide as a crosslinker, and then organic montmorillonite or organic attapulgite was introduced as filler into superabsorbent. The characterization of the polymer was confirmed by FTIR. Then the influence of attapulgite and montmorillonite to the superabsorbent were systematically optimized to achieve a superabsorbent with swelling capacity as high as possible.

Abstract: A novel xanthan-g-poly (acrylic acid)/ organic montmorillonite (XG-g-PAA/OMMT) superabsorbent polymer were synthesized by free-radical graft polymerization in aqueous solution using potassium persulfate as a free radical initiator and methylenebisacrylamide as a crosslinker, and then organic montmorillonite (OMMT) was introduced as filler into superabsorbent. The effects of reaction variables were systematically optimized to achieve a superabsorbent with swelling capacity as high as possible. Under the optimal synthesis condition, the polymer attained the best water absorbency of 882 g/g in distilled water and 107 g/g in 0.9 wt% NaCl solution. And such excellent character could be important to use in many fields, for example, in agricultural and horticultural applications.

Abstract: The new electrospinning technology NanospiderTM offering a realistic potential for industrial production was used for creation of nanofiber sheets from aqueous solutions of partially neutralized poly(acrylic) acid with crosslinking agent. Produced nanofiber sheet was crosslinked by heat treatment. Absorption capacity and rate of absorption were tested and compared with superabsorbent particles and commercial superabsorbent fibers. The morphology of electrospun fibers was observed using a scanning electron microscope (SEM). Possibilities of fiber diameter influence were studied.