Single-Chain Polymers Achieved from Radical Polymerization under Single-Initiator Conditions

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• 作者：Shen Zhang ; Xiangchao Pang ; Dameng Guo ; Bo Zheng ; Shuxun Cui ; Hongwei Ma
• 刊名：Langmuir
• 出版年：2012
• 出版时间：October 23, 2012
• 年：2012
• 卷：28
• 期：42
• 页码：14954-14959
• 全文大小：358K
• 年卷期：v.28,no.42(October 23, 2012)
• ISSN：1520-5827

文摘

Radical polymerization from a single initiator molecule in a microenvironment is a nearly ideal system in which bimolecular termination, solution concentration, and viscosity changes could be neglected. In this study, we provide two facile methods of preparing polymers via atom-transfer radical polymerization (ATRP) under single-initiator conditions: tether initiators on planar substrates at superlow density through mixed self-assembled monolayers (SAMs) and encapsulated single initiators in microfluidic droplets. The molecular weight (MW) of the resultant polymers characterized by atomic force microscope-based single-molecule force spectroscopy (AFM-based SMFS) showed that the single-chain ATRP had an extraordinarily faster chain propagation rate (2 unit/s) on planar substrates and gave polymers with much higher MWs (10⁵鈥?0⁶ g/mol) than those obtained from traditional ATRP (10³鈥?0⁵ g/mol). The former method offered a general platform for single-chain polymer synthesis and investigation, and the latter could be amplified to obtain abundant single-chain polymers with ultrahigh molecular weight (UHMW) for commercial applications.