聚合诱导分相制备聚丙烯酸@壳聚糖核壳乳液和微球的研究OACHSSCD

This study aims to construct a microfluidics-based polymerization-induced phase separation(PIPS)system.Through systematic investigation of experimental conditions,it is determined that the optimal component ratios and curing conditions are as follows:acrylic acid(AA)with a mass fraction of 10％,chitosan(CS)with a mass fraction of 0.5％～1.0％,N,N'-methylenebisacrylamide(MBA)with a mass fraction of 1.0％,and the output power of UV light source of ≥70％.These optimized conditions enable the controllable preparation of core-shell structured PAA@CS microdroplets and microspheres.An aqueous solution of AA,MBA,and CS was used as the dispersed phase,while liquid paraffin containing EM-90 served as the continuous phase.Uniform droplets were generated through a coaxial microfluidic device and subsequently subjected to UV irradiation to trigger polymerization and phase separation.The effects of the mass fractions of AA,MBA,and CS,together with UV intensity,on the core-to-shell radius ratio(r/R)and phase separation behavior were systematically investigated.The morphology and internal structure of the cured microspheres were further characterized.The results show that adding CS was essential for the formation of a core-shell structure.When the mass fraction of MBA was between 0 and 2％,r/R varied nonlinearly with MBA content.Increasing the AA content led to a significant decrease in r/R.When the output power of UV light source was below 40％,no obvious phase separation occurred.Under optimal conditions,the average particle size of uncrosslinked core-shell droplets is approximately 434 μm.After crosslinking,the solid microspheres maintain a well-defined spherical shape and intact core-shell structure,with an average particle size of 240 μmn.The combination of microfluidics and polymerization-induced phase separation enables the controllable fabrication of core-shell PAA@CS microdroplets and microspheres.Among the optimized conditions,the components ratios including AA(10％),CS(0.5％-1.0％),and MBA(1.0％),together with an UV curing intensity of ≥70％,jointly regulated the formation of the PAA core and the structural stability of the core-shell structure.This study provides a feasible strategy for the design and application of functional core-shell microspheres.