Title of article :
Temperature- and pH-responsive star amphiphilic block copolymer prepared by a combining strategy of ring-opening polymerization and reversible addition–fragmentation transfer polymerization
Author/Authors :
Jianhua Zhou، نويسنده , , Li Wang، نويسنده , , Jianzhong Ma، نويسنده , , Jianjun Wang، نويسنده , , Haojie Yu، نويسنده , , Anguo Xiao، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2010
Pages :
11
From page :
1288
To page :
1298
Abstract :
The star-shaped poly(ε-caprolactone)-b-poly(2-(dimethylamino)ethyl methacrylate) (HPs-Star-PCL-b-PDMAEMA) was synthesized by ring-opening polymerization and reversible addition–fragmentation chain transfer (RAFT) polymerization. Star-shaped polycaprolactones (HPs-Star-PCL) were synthesized by the bulk polymerization of ε-caprolactone (CL) with a hyperbranched polyester initiator and tin 2-ethylhexanoate as a catalyst. The number-average molecular weight of these polymers linearly increased with the increase of the molar ratio of CL to hyperbranched initiator. HPs-Star-PCL was converted into a HPs-star-PCL-RAFT by an esterification of HPs-Star-PCL and 4-cyanopentanoic acid dithiobenzoate. Star amphiphilic block copolymer HPs-Star-PCL-b-PDMAEMA was obtained via RAFT polymerization of 2-(dimethylamino)ethyl methacrylate (DMAEMA). The molecular weight distribution of HPs-Star-PCL-b-PDMAEMA was narrow. Furthermore, the micellar properties of HPs-Star-PCL-b-PDMAEMA in water were studied at various temperatures and pH values by means of dynamic light scattering (DLS). The results indicated that the star copolymers had the pH- and temperature-responsive properties. The release behaviors of model drug aspirin from the star polymer indicated that the rate of drug release could be effectively controlled by pH value and temperature.
Keywords :
Star amphiphilic block copolymer , RAFT polymerization , pH and temperature sensitivity , Controllable drug release
Journal title :
European Polymer Journal(EPJ)
Serial Year :
2010
Journal title :
European Polymer Journal(EPJ)
Record number :
1228448
Link To Document :
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