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47. Alternating crystalline-amorphous layers in hybrid block copolymers of linear poly(ethylene glycol) and dendritic poly(benzyl ether)
writer:Xuexin Duan, Fei Yuan, Xiaojing Wen, Miao Yang, Binglin He, Wei Wang*
keywords:crystalline-amorphous layers; crystalline morphology; dendrimers; hybrid block copolymers; poly(benzyl ether); poly(ethylene glycol)
source:期刊
specific source:Macromolecular Chemistry and Physics
Issue time:2004年

In the present work, we have studied the crystalline morphology of hybrid di- and triblock copolymers consisting of linear poly(ethylene glycol) (PEG) and Fréchet-type monodendrons of poly(benzyl ether). The linear blocks can crystallize to form spherulites under supercooling condition. Using atomic force microscopy and small-angle X-ray scattering method we found alternating crystalline and amorphous layers. The crystalline layers are formed by the PEG block, while the amorphous layers contain the miscible mixture of PEG and the monodendrons. Our analysis shows that the long period, d, of the layers scales as d ∝ Mmath image where equation image is the molecular weight of the monodendrons. As the radius of gyration of the monodendrons Rg, also scales as Rg ∝ Mmath image (B. M. Tande, et al. Macromolecules2001, 34, 8580), we obtain d ∝ Rg, implying a linear increase of the long period with the radius of gyration of the monodendrons.