Double-Grafted Cylindrical Brushes: Synthesis and Characterization of Poly(lauryl methacrylate) Brushes

✍ Scribed by Youyong Xu; Harald Becker; Jiayin Yuan; Markus Burkhardt; Yong Zhang; Andreas Walther; Sreenath Bolisetty; Matthias Ballauff; Axel H. E. Müller

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 277 KB
• Volume: 208
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.200700097

✦ Synopsis

Abstract

Double‐grafted cylindrical brushes with poly(lauryl methacrylate) (PLMA) as the side chains were synthesized using the grafting‐from strategy via atom transfer radical polymerization (ATRP). The polyinitiator poly[2‐(2‐bromoisobutyryloxy)ethyl methacrylate] (PBIEM) with $\overline {DP} _{\rm n}$ = 240 and 1 500 served as the backbone. The PLMA side chains of the brushes carry long alkyl chains. GPC and ^1^H NMR measurements confirmed the successful formation of the PLMA cylindrical brushes. The side chains were cleaved from the cylindrical brushes by transesterification. GPC and ^1^H NMR results indicate that the initiating efficiency of the bromoester groups on the backbone for the bulky monomer was in the range of 0.34 ≤ f ≤ 0.67. Static and dynamic light scattering show that the ratio of the radius of gyration to the hydrodynamic radius, R~g~/R~h~, is in the range of 1.2–1.3, indicating that the LMA cylindrical brushes are semiflexible in solution. Atomic force microscopy (AFM) measurements show that short PLMA brushes exhibit a spherical morphology while the long brushes exhibit a worm‐like structure. DSC displayed melting peaks at around −30 °C, indicating the alkyl side chains of the PLMA chains in the double‐grafted cylindrical brushes are crystallizable.

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