Preparation And Drug Release Properties Of Whole Cellulose Composite Aerogels

Cellulose nanofibers（CNF）are biodegradable materials with light weight and low density.Due to its high mechanical strength and aspect ratio,CNF is an ideal reinforcing phase for composite materials.And with the development of new cellulosic solvents,the research of cellulosic composites based on regenerated cellulose has become a hot spot.In this paper,CNF was obtained from purified bagasse bleaching pulp by lapping and high-pressure homogenization.CNF was used as the reinforcing phase.The bagasse bleaching pulp was dissolved by AmimCl,and CNF was added as the reinforcing phase to prepare the whole cellulose composite aerogel by dissolution-regeneration process which embedded the high crystallinity cellulose into regenerated cellulose matrix.And the effect of CNF addition on the shrinkage,morphology,pore size distribution,specific surface area and thermal stability of the composite cellulose aerogels was studied.Finally,the study of composite cellulose aerogels for loading PCTM was carried out,and the feasibility of the aerogels used in drug carriers was discussedThe main conclusions are as follows:1.The uniform size of CNF from chemically purified bagasse bleaching pulp could be prepared by grinding and high-pressure homogenization.After the purified cellulose was dissolved and regenerated in AmimCl,its functional group did not change,but XRD analysis showed that the cellulose before and after dissolution changed from cellulose type I to cellulose type II,and its thermal stability decreased.2.The total cellulose composite aerogels were tested and analyzed.It was found that the shrinkage of the total cellulose composite aerogels with CNF addition decreased compared with the regenerated cellulose aerogels.And in the micro morphology,regenerated cellulose and CNF formed cross-linking,the specific surface area increased,and the thermal degradation changed to second-order degradation.3.The total cellulose composite aerogels with different CNF ratios well loaded PCTM,and its equilibrium swelling rate was greatly affected by CNF ratio and drug loading.With the increase of CNF ratio and drug loading rate,the equilibrium swelling rate of total cellulose composite aerogels increased.4.When the pH value was 7.4,the drug release rate of the whole cellulose composite aerogel was mainly affected by CNF content,but it was greatly affected by pH,when pH value was 3.The initial release rate and final release rate of C₂ were higher than those of other cellulose aerogels containing regenerated cellulose.In contrast,the whole cellulose composite aerogels had better sustained release properties.