Synthesis And Properties Of Hemicellulose Super Absorbent Resin

With the improvement of people's living standard,the change of consumption concept and the longing for the ECO-life,clothing characteristics have been gradually changed from the original warm type to comfortable,healthy,environmental type.Synthetic fiber,which is the main material of original clothing fabrics,is less comfortable and environmental-friendly.And the above disadvantages can be solved by viscose fiber.A large amount of waste liquid can be produced in the process of producing viscose fiber,and the waste liquid's disposal has become a bottleneck of viscose fiber industry.Especially the waste water containing hemicellulose and caustic soda has a poor biodegradability,and if it is discharged directly,serious water pollution will be caused and amounts of hemicellulose resources will be wasted.Therefore,in order to solve the problem preliminarily and achieve the purpose of turning waste into treasure,the super water absorbent resin was synthesized with the waste liquid containing hemicellulose and caustic soda as raw material.In order to determine the synthesis methods of the hemicelluloses super water absorent resin,the hemicellulose grafted acrylic acid?AA?super water absorbent resin was prepared by conventional water bath heating method,microwave irradiation method and ultrasonic assisted microwave irradiation method,respectively,using AA and the waste liquid which contains a large amount of hemicellulose and caustic soda as raw material.The effects of the materials proportion and the reaction conditions on the grafted effect of hemicellulose and the resin's water absorbency were studied through the single factor method and then the suitable formula and the reaction conditions for the synthesis of resin were determined,respectively.And the structure of the resin prepared by three different methods was analyzed by FT-IR and the target product was proved to have been synthesized.The reaction rate in the process of synthesis and the water performance of synthetic resin were considered comprehensively.The results indicated that microwave irradiation method was the suitable method on preparing hemicellulose grafted AA super water absorbent resin under laboratory scale.Because the reaction rate of microwave radiation method was fast and the water absorption performance of the resin prepared by microwave irradiation method under the suitable synthesis conditions was good.The resin had the water absorption of 637g.g^-11 in distilled water,321g.g^-11 in the tap water,95g.g^-11 in the 0.9 wt%NaCl solution and 35g.g^-11 in the artificial urine solution and the resin exhibited good water retaining capacity and reusing ability.In addition,the resin could reach equilibrium water absorbency within 100 min,so it had good water absorption rate.The water absorption performance of the hemicellulose grafted AA super water absorbent resin prepared by conventional water bath heating method need to be increased.Four kinds of modified resin were synthesized in this paper through adding four kinds of functional monomer,respectively,including Sodium styrene sulfonate?SSS?,N-hydroxymethyl acrylamide?NMA?,2-Hydroxypropyl acrylate?HPA?,Triethylene glycol diacrylate?TEGDA?,on the hemicellulose grafted AA super water absorbent resin to change the properties.The effect of the amount of functional monomer on the water absorbency of the resin was discussed and then the suitable dosage of the functional monomer was determined.The water absorption performance of modified and original resin were discussed and compared.The results indicated that the water absorption performance of modified resin was increased to some extent.Concretely,the hemicellulose-AA-SSS copolymer modified super water resin had the water absorption of 862g.g^-1 in distilled water and 132g.g^-1 in 0.9 wt%NaCl solution,which were nearly three times as high as original resin's,and the resin could reach equilibrium water absorbency within 120 min,which was nearly doubled as fast as original resin's.In addition,the water retention rate of hemicellulose-AA-HPA copolymer modified super water absorbent resin could reach 40%in water loss after eight hours.Accordingly,the special structure of four kinds of functional monomer had different effects on the water absorption of the modified resin.The resin's water absorption and surface structure were considered comprehensively and the result indicated that the water absorbency and the water absorption rate of the resin were increased with the increase of surface roughness and specific surface area.In conclusion,the hemicellulose super water absorbent resin was synthesized successfully with the waste liquid which contains a large amount of hemicellulose and caustic soda as raw material,which meaned the waste liquid was utilized highly effective,a difficult problem on the production of viscose fiber manufacturers was solved and another super water absorbent resin was provided.