Study On The Synthesis And Performance Of Cellulose Modified Super Absorbent Resin

Cellulose is abundant natural polymer renewable resource in nature,and it has attracted the attention of researchers from various countries with its excellent properties.Cellulose modified high water absorbent resin has become a hot topic in today's research.In order to improve absorption,gel strength,strong salinity tolerance of high water absorbent resin,in this paper,acrylamide(AM)was selected for the main monomer,ammonium persulfate(APS)and N,N'-Methlenebisacrylamide(MBA)were selected for crosslinking agents.Two anionic monomers:2-acrylamide-2-methylpropesulfonate and 2-acrylamide-tetradecanesulfonic acid sodium salt(NaAMC14S)were chosen to be synthesized by graft copolymerization of hydroxymethyl cellulose(CMC)respectively and together,thus,three high water absorbent resins were synthesized.The synthesis conditions of resin were optimized by single factor method,the influence of CMC dosage,monomer ratio,initiator and crosslinking-agent on resin's synthesis and properties.Therefore,high water absorbent resin with excellent properties was obtained and its properties were tested,and the structure and surface morphology of it was characterized by FT-IR and-SEM.The optimization conditions of-three kinds of synthetic resin were as follows:the optimization condition of CMC-g-P(AM-co-AMPS):the solid content of 20wt%,w(CMC)=10wt%,w(AM)=67.5-wt%,w(AMPS)=22:5wt%,initiator w(APS)=0.15wt%,crosslinking agent w(MBA)=0.1wt%.The optimization condition of CMC-g-P(AM-co-NaAMC:4S):the solid content of 20wt%,w(CMC)=10wt%,w(AM)=89.07wt%,w(NaAMC14S)=0.93wt%,initiator w(APS)=0.2wt%,crosslinking agent w(MBA)=0.2wt%.The optimization condition of.CMC-g-P(AM-co-AMPS-NaAMC14S):the solid content of 20wt%,w(AMPS)=15wt%,w(NaAMC14S)=0.25wt%,w(CMC)=10wt%,w(AM)=74.75wt%,initiator w(APS)=0.15wt%,crosslinking agent w(MBA)=0.15wt%.The hydrolysis degree(HD)was 80%,and the reaction temperature was 70? and the reaction time was 4h in the optimization condition of the three resins.Besides,the addition of the initiator APS and crosslinking agent MBA was calculated according to the mass fraction of the monomer.The absorption rate of three kinds of resin in deionized water and 0.9wt%NaCl aqueous solution was tested,respectively.Under the condition of 30,60,and 100?,standing it for 2 h,the water retention rate for deionized water was tested,respectively.In addition,after 45 minutes' centrifugate at the speed of 1000rpm and 12000rpm,the water retention rate was tested,respectively.The absorption rate of CMC-g-P(AM-co-AMPS)was 973.1g/g and 100.3g/g,respectively in the two soultions and the water retention rate of deionized water at three temperatures was 84.2%,48.6%and 36.8%,respectively,and the water retention rate at two speeds was 97.49%and 51.78%,respectively.The absorption rate of CMC-g-P(AM-co-NaAMC14S)was 1425.6g/g and 78.6g/g,respectively,in two solutions,and the water retention rate of deionized water at three temperatures was 89.6%,68.6%and 50.3%respectively,and the water retention rate at two speeds was 99.94%and 73.7%respectively.The absorption rate of CMC-g-P(AM-co-AMPS-co-NaAMC14S)was 1887.6g/g and 129.7g/g,respectively in the two soultions,and the water retention rate of deionized water at three temperatures was 90.4%,67.4%and 53.2%respectively and the water retention rate of the two speeds was 99.94%and 79.98%respectively.The performance of CMC-g-P(AM-co-AMPS-co-NaAMC14S)resin was optimal,so the resin was selected for the experiments of adsorption of heavy metal ions Cu2+ and Pb2+.In the solution of Cu2+,Pb2+heavy metal ions with the concentration of 200mg/L,respectively,when the pH was around 4,the adsorption time was 12h,and the dosage of adsorbent was 001t%,the adsorption rate can reach to 82.17%and 77.87%respectively.When the dosage of adsorbent was 0.02wt%,the adsorption rate was 83.35%and 81.26%.When the dosage of adsorbent was 0.14wt%,the adsorption rate of Cu2+and Pb2+was as high as 92.37%and 93.31%.The experimental resulted show that the resin has excellent adsorption properties for heavy metal ions and has good application prospect.The innovation of this paper lies in the introduction of salt-tolerant hydrophilic monomer AMPS and long chain hydrophobic monomers NaAMC14S,on the basis of adding acrylamide monomers;the salt resistance of salt-tolerant groups of AMPS and the hydrophobic association of NaAMC14S hydrophobic groups were used.Through the interaction of different groups,absorption rate,gel strength and resistance to temperature,salt and pressure were improved,so that the resin has excellent application performance.The SEM tests also proved that the resin has a better spatial network structure,which provided new ideas and practical applications for the synthesis of resins.