| 摘 要： | Polystyrene microspheres with polyglycidol (polyGL) in a surface layer were synthesized in batch radical emulsifier-free
emulsion copolymerizations of styrene and surfmers, α-t-butoxy-ω-vinylbenzyl-polyGL macromonomers (VB-polyGL). Macromonomers
with number-average molecular weight Mˉ
n=950 (VB-polyGL950) and Mˉ
n=2700 (VB-polyGL2700) were used for these polymerizations. In all syntheses the initial concentrations of styrene and initiator
(K2S2O8) were constant. The initial macromonomer-to-styrene ratios were varied from 1.10 × 10−3 to 1.64 × 10−2 mol/mol and from 3.46 × 10−4 to 3.47 × 10−3 mol/mol for VB-polyGL950 and VB-polyGL2700, respectively. The diameters of microspheres obtained were smaller for the syntheses
with higher concentrations of macromonomers. Syntheses with VB-polyGL950 yielded microspheres with number-average diameters
(Dˉ
n) from 216 to 900 nm and with a bimodal diameter distribution. The number-average diameters of microspheres obtained with
VB-polyGL2700 varied from 220 to 650 nm, depending on the initial concentration of macromonomer. Their diameter distributions
were monomodal, with a diameter polydispersity parameter (ratio of weight-average and number-average diameters) in the range
1.007≤Dˉ
w/Dˉ
n≤1.022. For each type of microsphere the fraction of polyGL in a surface layer and the surface concentration of sulfate anions
were determined. The fraction of polyGL in the surface layer was related to the initial monomer composition in the polymerizing
mixture. Adsorption of human serum albumin onto surfaces of some poly(styrene/VB-polyGL) microspheres was up to 10 times lower
than for the polystyrene microspheres obtained in a similar emulsifier-free emulsion polymerization of styrene.
Received: 26 September 2000/Accepted: 19 February 2001
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