The Synthesis And Characterization Of Superabsorbent Polymer Based On Pouce Cellulose

Superabsorbent polymer is a lightly cross-linked hydrophilic polymer capable of absorbing water from tens to thousands of times its own weight.It is widely used in sanitary products,agricultural and horticultural water holding material,and various other fields.Cellulose is one of the most abundant natural resources,which is renewable,nontoxic and biodegradable.It has been paid more and more attention by researchers of many countries.In this thesis,the pouce is used as raw material,which is a kind of waste.And the pouce cellulose was separated from pouce by alkali cooking method.The superabsorbent polymer based on pouce cellulose was synthesized in both solution polymerization and microwave heating polymerization,and the optimum conditions have been obtained.The functional group of the pouce cellulose-g-acrylic acid composite was confirmed by FTIR.The morphology of the SAP was observed by SEM.The structure was analyzed by XRD.The thermodynamics stabilization was analyzed by TG.At the same time,the properties were measured such as the absorbency rate,water retention,the absorbency in different electrolyte solution,the adsorption of heavy metal cation and biodegradability in soil.In solution polymerization,the optimum conditions have been obtained through the orthogonal experiments.The initiator dosage is 0.12 g.The acrylic acid dosage is 6.52 g.The neutralization percentage is 70%.The cross-linking agent dosage is 0.014 g.The reaction temperature is 65℃and the initiating time is 15 min.The average absorbency in double distilled water,mixed fertilizer solution and 0.9%NaCl solution of the SAP is 2952.96 g/g, 830.66 g/g and107.12 g/g under the conditions,respectively;and the three CV is 3.51%,1.75 %and 1.93%,orderly.In microwave heating synthesis,the optimum conditions have also been obtained.The microwave power is 160 W.The initiating time is 15 min.The reaction time is 7 min.The initiator dosage is 0.16 g.The AA dosage is 7.15 g.The neutralization percentage is 65%,and the cross-linking agent dosage is 0.010 g.The average absorbency in double distilled water, mixed fertilizer solution and 0.9%NaCl solution of the SAP is 991.44 g/g,363.77 g/g and 55.53 g/g;and the three CV is 5.57%,4.64%and 3.38%,respectively.The pouce cellulose-g-acrylic acid composite was confirmed by FTIR.The morphology of the SAP was observed by SEM.It shows that both of them have the porous structure,and the SAP under microwave heating condition is better than in solution polymerization in network structure and membrane after swelling in solution.It was confirmed that the two synthesized SAP have no crystalloid by XRD,and the crystalloid structure of the pouce cellulose was confirmed.The excellence thermodynamics stabilization was showed by TG. The properties of the two SAP has been measured.As a result,both of them at 80-120 particle size have the maximum absorbency;they can get almost the maximum absorbency in only 2 min,and the speed of absorbent in double distilled water is high;the property of retention is good,and the SAP under microwave condition is better than in solution polymerization;the absorbeny decreased with increasing temperature;pH has effect on the absorbency,the absorbency could decrease in acidity or alkalescence solution;both of them can absorb the simulation blood and emiction;they can be used several times,and the microwave SAP can be better than the other;the absorbency decreased with increasing concentration in different electrolyte solution;Cu²⁺ and Pb²⁺ can be adsorbed by them,and it is good for protecting soil and agriculture;the two SAP can be biodegradable in the soil microorganism partly,and the rate of the SAP in solution polymerization is faster than the other.