Synthesis And Properties Of Superabsorbent Resin Of Polyvinyl Alcohol/Acrylicacid/Acrylamide

Superabsorbent resin which has cross-linked structure and lots of hydrophilic groups on its molecular chain is a water-soluble polymer material with three-dimensional network structure. Superabsorbent resin possesses of wonderful water-absorbing ability and water-holding capacity. Compared to the other superabsorbent polymers, the polymer which synthesized from acrylic and acrylamide has been widely used in many fields, and has perfect water absorbency and simple preparation technology. In this thesis, two different superabsorbent resins prepared with acrylic acid(AA), acrylamide(AM) and polyvinyl alcohol(PVA) are studied.Superabsorbent of poly(acrylic acid- acrylamide)(PAAAM) was prepared firstly. The heating mode and added way of initiator and crosslinking agent that have influence on the performance of product was studied, and the optimal synthesis conditions for PAAAM superabsorbent were obtained by the orthogonal test. The results showed that gradual raise of the temperature can make a stable condition of the reaction, and the using the solution of initiator and crosslinking agent can simplify experimental operation and improve the performance of PAAAM. The optimal synthesis conditions for PAAAM were as follow. The amount of AM, cross linker, initiator was 15%, 0.03%, and 0.4%, respectively. The neutralization degree of acrylic acid was 75%, and the monomer concentration was 25%. The absorbency of deionized water and 0.9% NaCl solution of PAAAM which prepared under optimal synthesis conditions was 1609 g/g and 85 g/g, respectively. Fourier transform infrared spectroscopy was used to ensure the target product was synthesized, and the surface of product was characterized by scanning electron microscope.PVA was added to PAAAM resin to form a semi-interpenetrating network(SIPN) structure, and superabsorbent of PVA/PAAAM which has SIPN structure was prepared. The influence of different factors on the properties of the resin was studied through the single factor experiment. The results showed that within a certain range the absorbency of PVA/PAAAM increased with the increase of the amount of various factors and the property of salt tolerance improved by adding PVA. The quantity of PVA, AM, cross linker and initiator was 10%, 15%, 0.05%, and 0.4%, respectively. The neutralization degree of acrylic acid was 75%, and the monomer concentration was 25%. The absorbency of deionized water and 0.9% NaCl solution of PVA/PAAAM which prepared under optimal synthesis conditions was 1290 g/g and 106 g/g, respectively. And PVA/PAAAM was able to obviously improve water absorbency ratio and retention performance of soil, especially sandy soil. Fourier transform infrared spectroscopy and phase analysis of x-ray diffraction were used to ensure that the target product was synthesized, and the surface of the product was researched by scanning electron microscope.