Superabsorbents properties

Argade A, Peppas N (1998) Poly(acrylic acid)-poly(vinyl alcohol) copolymers with superabsorbent properties. J Appl Polym Sci 70 817-829... 

Chen, J. Park, H. Park, K. Synthesis of super-porous hydrogels hydrogels with fast swelling and superabsorbent properties. J. Biomed. Mater. Res. 1999, 44, 53-62. 

Superporous hydrogels (SPHs) ate materials developed to demonstrate fastswelling and superabsorbent properties (Omidian et al., 2005). These were initially proposed as gastric retention devices however, SPHs may be tailor-made for other applications in pharmaceutical arxl biomedical industries (Omidian et al., 2007). The high swelling pressure of SPHs can potentially be used to trigger an alarm system upon the incursion of water and hence, can be utilized as smart hydrogels or sensors for various apphcations. 

Argade and Peppas [ 100] examined copolymers of PVA and PAA for their superabsorbent properties. A functionalized PVA was copolymerized with acrylic acid to prepare such materials. Additionally, the degradation of the PVA links between PAA chains was examined to determine the possible biodegradation to lower molecular weight polyacrylates. 

Undoubtedly, the properties of superabsorbent hydrogels occupy the key position in the problem under consideration. Being directly connected with the network formation reaction, they provide all necessary information about the details of this process. Also, the SAH properties are found to be the most reliable basis for understanding and predicting their behavior in real systems, i.e. in the soil, in contact with plants, in physiological media, etc. 

J. Zhang, L. Wang, A. Wang, Preparation and properties of chitosan-g-poly(acrylic acid)/montmorillonite superabsorbent nanocomposite via In situ intercalative polymerization, Ind. Eng. Chem Res., vol. 46, pp. 2497-2505, 2007. 

In this context numerous changes were made. The chapter Properties of Polymers was revised and a new section Correlations of Structure and Morphology with the Properties of Polymers was added. The chapter Characterization of Macromolecules was revised and enlarged. 15 examples have been deleted as they did no longer represent the state of the art and/or were of minor educational value. Several new experiments (plus background text) were added, as, for example controlled radical polymerization - enzymatic polymerization - microemulsions - polyelectrolytes as superabsorbants - hyperbranched polymers - new blockcopolymers - high impact polystyrene - electrical conducting polymers. 

Super slurper has wondrous properties, and it amazed people when it was first demonstrated. For some time no one seemed to know how to exploit its potential, then in 1968 chemists came up with the idea of incorporating polyacrylates into diapers, Here was a way to keep urine away from a baby s bottom and reduce diaper rash. The Japanese, always at the forefront of high-tech innovation, ate it up. Not literally, of course, but they could have — toxicity tests showed that the material was remarkably safe. By 1984 North Americans had also discovered the advantages of superabsorbent diapers, and the product rapidly dominated the market. Soon feminine hygiene products were also incorporating the new technology, as were adult incontinence products. 

In this section, we want to present some recent results which have been obtained by B. Mann using ESPResSo, and explain, how this has been done [41,43,47]. The system under investigation is a polyelectrolyte network, i.e. a gel of cross-linked charged pol uners. One of the most prominent features of such a network is that it is able to absorb large amounts of the solvent, up to several hundred times its dry mass. Due to its remarkable properties, this hydrogel has many industrial applications, e.g. as superabsorbants in diapers,... 

Nonaka, T. Yamada, K. Watanabe, T. Kurihara, S. Preparation of superabsorbent polymer hydrogels from trialkyl-4-vinylbenzyl phosphonoium chloride-acrylamide-methylenebis-acrylamide copolymer and their properties. J. Appl. Polym. Sci. 2000, 78, 1883-1884. 

Masuda, F. Properties of superabsorbent polymers. In Super absorbent Polymers Kyoritsu Shuppan Tokyo, 1988 51-80 (written in Japanese). 

Sometimes, the ability of certain polymers to repel water is useful— this property is what keeps you dry when you wear a raincoat. Other times, it is desirable for polymers to absorb water. This is why wool socks keep your feet warm by wicking water away from your skin and why a diaper helps keep a baby dry. Cloth diapers are made of cotton, a natural polymer that absorbs water well. Why do disposable diapers hold so much more water than cloth diapers They contain a superabsorbent polymer that can hold hundreds of times its weight in water. In this MiniLab, you will determine how much water the polymers in two different brands of diapers can hold. 

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