Polymer Micro- and Nanografting

By Celestino Padeste and Sonja Neuhaus

Polymers have proven to be very suitable materials for topographic structuring, in particular in nanoreplication processes. Micro- and Nanografting strategies address the possibility for the formation of chemical patterns and structures on or in polymeric substrates using relatively simple processes. Polymer Micro- and Nanografting focuses on grafting techniques characterization and applications for the particular combination of polymer layers on polymer substrates. The authors, leaders in this area of research, provide a comprehensive survey on polymer-on-polymer grafting, covering the latest developments and future applications.

• Provides a comprehensive survey on polymer-on-polymer grafting, covering the latest developments and future applications
• Focuses on grafting techniques, characterization and applications for the particular combination of polymer layers on polymer substrates
• Concentrates on the combination of structuring methods and chemical functionalization of polymers
• Addresses the possibility for the formation of chemical patterns and structures on or in polymeric substrates

• Language: English
• Publisher: Elsevier Science
• Release date: Feb 10, 2015
• ISBN: 9780323354066

Celestino Padeste

Celestino Padeste (born 1961 in Zürich/Switzerland) studied chemistry at the University of Zürich, from where he received a PhD degree in 1989 in the field of inorganic solid state / gas phase reactions. After a Post-Doc at the University of New South Wales in Sydney/Australia, which was focused on surface analysis of catalyst systems, he was in 1993 employed at the Micro- and Nanotechnology Laboratory at the Paul Scherrer Institute in Villigen/Switzerland, in the frame of a biosensor project in the molecular nanotechnology group. Since 2003 he is a senior scientist in the polymer nanotechnology group in the same laboratory. His research is focused on the design of functional surfaces by combination of micro- and nanostructuring methods, including synchrotron-based lithography, with chemical surface modification, polymer grafting and protein immobilization. He is supervising PhD students and Post-Docs in basic and application-related research projects. He is a coauthor of more than 75 scientific papers and 4 patents.

Book preview

preparation.

Chapter 1

Functional Polymer Structures

Polymer micro- and nanografting is introduced in the context of different methods to locally endow polymers with selected functionalities. The second part of the chapter gives an introduction to polymer brushes, which are readily accessible using grafting techniques and have a high application potential as functional coatings. Fundamentals of their formation and conformation dependent on environmental conditions are summarized, as are functionalities provided by various brush systems.

Keywords

Inert polymers; functional polymers; polymer functionalization; polymer substrate; polymer device; structuring methods; polymer brush; polyelectrolyte

Materials with a multitude of functionalities have been introduced in our daily lives and are used without thinking much about their origin and way of production. Examples include magnetic, electrical, optical, and biological functions, and many of them are implemented in polymeric or polymer-based systems. This chapter focuses on the chemical properties and related functionalities that can be introduced to polymer systems using different methods. Main emphasis is placed on polymer brushes, which are extremely versatile and interesting for the functionalization of surfaces and which are accessible on polymers using grafting technology.

1.1 Polymer Systems: Inertness Versus Functionality

Polymers are the most promising materials for current and future applications due to their special properties: They have low densities, exhibit relatively high specific strength and flexibility, and in some cases display remarkable chemical inertness (e.g., fluoropolymers and polyaryletherketones). For many applications, the chemical inertness of polymers provides a substantial advantage. Chemically inert polymers are long-lasting and stable, resistant to weathering, and show very low sorption of water. To benefit from these properties, polymeric coatings are often used as the finish for surfaces of daily life goods, applied in order to achieve (chemical) inertness and stability.

In contrast, other classes of polymers are not inert. They may interact strongly with the environment and adopt special functions. Examples include specific interactions with molecules and ions exploited in separation and purification techniques; electrical and optical properties used in polymer solar cells, organic light emitters, and optical elements; as well as properties relevant for bio-applications, such as anti-biofouling properties and specific binding of proteins.

Adding locally defined functionality to inert surfaces is interesting for many applications. For instance, integration of small sensing elements that could—actively or passively—monitor the freshness of packed goods is of great interest to the packaging industry. With current structuring and patterning technologies, length scales can be addressed which are interesting for studying interactions with cells. Such studies are of importance for the functional design of polymeric implants. Further developments of patterning technology to reach dimensions of the size of single protein molecules are in progress, which will be beneficial for constructing ultrasensitive bioanalytical