Stnthesis and characterization of hyperbranched polycarbosilane-g- cyclodextrin polymer brushes

Hyperbranched polycarbosilane-g-β-cyclodextrin (β-CD) polymer brushes based on carbosilane core were synthesized. At first, hyperbranched polycarbosilanes (HBP) with carbosilane cores of 3 to 5 generations were prepared via hydrosilylation addition and pseudo-one-step using methyldiallylsilane as monomer (AB₂) and 1,2-bis (diallyl(methyl )silyl) ethane as core (B₄), respectively. Then, HBP was modified by 1,1,3,3-tetrmethyldisiloxane, allyl alcohol and chloroacetyl chloride for obtaining hyperbranched polycarbosilanes carrying chloride atoms (HBP-Cl). It may which act as a macroinitiator for further polymerization of a hyperbranched polymer with functional arms. For this purpose, HBP-g-poly(N, N-dimethylaminoethyl methacrylate) (PDMA) with different arm length was synthesized by atom transfer radical polymerization (ATRP) . Finally, HBP-g-PDMA-β-CD with functional polymer brushes was obtianed by immobilization of Mono-6-I-β-CD onto PDMA chains.Their macromolecular structures were characterized by FTIR,¹ H-NMR,¹³ C-NMR and ²⁹Si-NMR-In addtion, the macromolecular architecture of HBP-g-PDMA-β-CD, including the inner HBP structure with carbosilane core and the exterior PDMAEMA layer, was confirmed by SEC/MALLS and particle size analyses. Besides, it was found that the amount of β-CD content incorporating onto PDMA segments can also be regulated by changing reaction time.