| Starch grafting cyanoarylate, a type of super water absorbent (SAP), was first characterized by C.R. Russell in 1960. As a kind of novel functional material, SAP is used in many fields such as the production of hygienic materials, medical adjuvants, agricultural and horticultural water retaining agents, cold keeping agents, heat preservation agents, sludge solidifying agents, food preservatives, thickening agents for fabric printing and dyeing, and other multiplex materials. SAP has become a basic material in industry and agriculture with millions of tons of applications annually. Its basic characteristics are as follows:①Super water absorbent capacity. SAP can absorb thousands of times its own weight to form a water gel, which in turn makes water lose its free flow characteristic. In this aspect, SAP can be used as a water carrier.②High water preserving character. Water is absorbed into the interior 3D net of SAP and then synchronizes with polymer molecules. In this manner, SAP can preserve water at temperature and pressure.③High-speed water absorbing ability. With additional treatment, SAP powder can reach even higher capacities.The main objective of the present paper is to research the factors that affect the performance of SAP and explore programs to promote its performance. These include hydration frequency and rate, which can be especially well suited for use in sanitary towels,baby paper diapers,and pads for adult incontinence in the manner of lightening weight and diminishing size. We also research methods to extend the life of cross-linked polyacrylic sodium. This thesis is divided into the following three parts:1. Preparation of SAP for hygienic materials1) Use ammonium persulfate-sodium sulfite as the initiator and methylene bisacrylamide (MBAA) as the cross-linking agent to synthesize the high performance crosslinking polyacrylic salt. This can then be treated by an additional process. We research many factors that influence multiple absorbency and confirm that synthetic SAP can reliably act as absorbent for 200-700 absorbent events. We also attempt to obtain a certain elasticity gel after the products absorbed water, avoid the so-called too high SAP, guarantee a good shaping nature, and offer the raw materials for further modification to improve absorbency and speed.Polymerization in water solution requires that the apparatus be low, facilely controlled, and yields benefits such as low pollution and ease of industrial production.2) Improving performanceOn the basis of getting raw materials, an added crosslinking reaction on the face of the particle produces a shell-core structural particle that has a heavy crosslinking density on the exterior but is less dense on the interior. By this method, we improve the speed of water absorbency,effectiveness of the interparticle transmission, dispersiveness, and water-retaining property with respect to artificial urine.2. Preparation of SAP for optical fiber cablesIn this part, we prepared high absorbent capacity crosslinked polyacrylic sodium and then repeat crosslinking on the SAP powder surface. In this manner, we can obtain an SAP water absorbent capacity of 470g/g with a speed of 1 min. However, the expansion speed is 10mm and the expanding high is 13mm. These are on the lower end of the index, and exhibit disparity from the standard– more study is necessary. 3. SAP for cool cap and performance improvement1) Copolymerization acrylic sodium and acryamide to prepare low water-absorbent capacity SAPThrough the study of acrylic sodium, acrylamide, and N,N'-methylene bisacrylamide in uniting copolymerization to reaction, we can prepare a high hardness SAP, a special-purpose polymer is compatible with icecap. The AA/AM copolymer has a good tenacity and is not easy broken, but will react with formaldehyde which decomposed from fabric and lost its water absorbing capacity.2) High hardness crosslinked polyacrylic acid sodium (PAAS)Polyacrylic acid sodium SAP was obtained by using low concentration initiator with a standard initiating temperature and increased crosslinking. Its absorbent capacity is about 100g/g; this kind of SAP is not sensitive to formaldehyde. PAAS SAP tenacity is not as good as that of the copolymer, as it usually crashed at pressure.3) Ultraviolet resistant SAPThe two above-mentioned kinds of SAP were treated by copper (Ⅱ) salt. The results were able to bear ultraviolet with a life-span 3 times that of the pre-treated SAP, making this suitable for many applications.
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