Graftlike Block Copolymer Bearing Biodegradable ε-Caprolactone Branches: A Facile Route to Hollow Nanocages

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• 作者：Youhua Tao ; Xiaoya Liu ; Dongjian Shi ; Mingqing Chen ; Cheng Yang ; Zhongbin Ni
• 刊名：Journal of Physical Chemistry C
• 出版年：2009
• 出版时间：April 16, 2009
• 年：2009
• 卷：113
• 期：15
• 页码：6009-6013
• 全文大小：168K
• 年卷期：v.113,no.15(April 16, 2009)
• ISSN：1932-7455

文摘

A graftlike block copolymer strategy was used to construct hollow nanocages with changeable cavity dimensions, where a graftlike block copolymer bearing biodegradable poly(ε-caprolactone) branches (PMAA-b-PFM) was prepared by the selective hydrolysis of block copolymer of tert-butyl methacrylate and macromonomer FM [CH₂C(CH₃)OOCH₂CH₂(OCOCH₂CH₂CH₂CH₂CH₂)₅OH] (PtBMA-b-PFM) precursor, which was synthesized by sequential controlled/living radical polymerizations of tBMA and FM. Self-assembling of PMAA-b-PFM into polymer micelles in water and cross-linking of the hydrophilic shell via condensation reactions between the carboxylic acid groups and the amino groups, followed by lipase degradation of the poly(ε-caprolactone) core, ultimately produces hollow nanocages. Transmission electron microscopy and laser light-scattering studies showed that the resultant hollow nanocages were nanoscale with narrow size distribution. Moreover, relative lengths of the hydrophobic and hydrophilic segments strongly influenced the hydrodynamic radius of the spherical micelles (52−101 nm) as well as the cavity size of the resultant hollow nanocages (62−85 nm in radius). The obtained polymeric nanocages should be useful in various fields, such as catalysis, drug delivery and structural material.