Preparation and Characterization of Cross-linked Hollow Poly(lactic acid) Microspheres
			        
					作者:B.B. JIANG, C.Y.GAO, J.C. SHEN
关键字:Emulsion polymerization,Polyl(lactic acid),Hollow microspheres
论文来源:期刊
具体来源:Chemical Journal of Chinese Universities
发表时间:2005年
Poly(lactic acid) macromonomer with a double bond at its end was 
synthesized by ring open polymerization of lactide catalyzed by stannous
 chloride in the presence of allyloxylethanol(AOE) as a co-initiator. 
Its molecular weight was decreased along with the adding amount of AOE. 
Initiated by an oxidation-reduction system, e.g. K2S2O8 and Na2SO3, the 
poly(latic acid) macromonomers were copolymerized with divinylbenzene 
and methacrylic acid in a water-in-oil-in-water emulsion manner to 
produce hollow microspheres with a size of hundreds nanometers. Their 
hollow structure was confirmed by transmission electron microscopy. 
Infrared spectroscopy measurement shows that the remainings of the 
microspheres after tetrahydrofuran extraction, constituting roughly 20 
of the sphere''s mass, contained all the initial monomer components. This
 provides a new pathway for fabricating biodegradable hollow 
microspheres with rather smaller size, which may find diverse 
applications in the fields of drug delivery, tissue engineering and 
nanotechnology.