Surface Modification of Polymers

Methods and Applications

Jean Pinson, Damien Thiry

• Publisher: Wiley-VCH
• Year: 2019
• Print ISBN: 9783527345410
• eBook ISBN: 9783527819232
• Edition: 1
• Topic: Technology & Engineering
• Subtopic: Materials Science
• Index: Technology & Engineering

A guide to modifying and functionalizing the surfaces of polymers

Surface Modification of Polymers is an essential guide to the myriad methods that can be employed to modify and functionalize the surfaces of polymers. The functionalization of polymer surfaces is often required for applications in sensors, membranes, medicinal devices, and others. The contributors?noted experts on the topic?describe the polymer surface in detail and discuss the internal and external factors that influence surface properties.

This comprehensive guide to the most important methods for the introduction of new functionalities is an authoritative resource for everyone working in the field. This book explores many applications, including the plasma polymerization technique, organic surface functionalization by initiated chemical vapor deposition, photoinduced functionalization on polymer surfaces, functionalization of polymers by hydrolysis, aminolysis, reduction, oxidation, surface modification of nanoparticles, and many more. Inside, readers will find information on various applications in the biomedical field, food science, and membrane science. This important book:

-Offers a range of polymer functionalization methods for biomedical applications, water filtration membranes, and food science
-Contains discussions of the key surface modification methods, including plasma and chemical techniques, as well as applications for nanotechnology, environmental filtration, food science, and biomedicine
-Includes contributions from a team of international renowned experts

Written for polymer chemists, materials scientists, plasma physicists, analytical chemists, surface physicists, and surface chemists, Surface Modification of Polymers offers a comprehensive and application-oriented review of the important functionalization methods with a special focus on biomedical applications, membrane science, and food science.

1
The Surface of Polymers

Rosica Mincheva and Jean‐Marie Raquez

University of Mons (UMons), Laboratory of Polymeric and Composite Materials, Center of Innovation and Research in Materials and Polymers (CIRMAP), 20, Place du Parc, 7000 Mons, Belgium

1.1 Introduction

Surface properties of any polymers have an imminent influence over key properties such as wetting, adhesion, friction, and biocompatibility, therefore affecting the applicability of a polymer material [1]. It is nowadays well accepted that surface properties differ from bulk in many aspects and a multitude of scientific works has been done for the last 70 years in an attempt to highlight what actually constitutes the surface, including the interphase, and how far into the material its surface goes [2–10]. Moreover, while classical surface model will consider a surface as rigid, immobile, and at equilibrium, which is more likely to be true for rigid solids, the surface of a polymer material is highly depending on time and temperature due to its viscoelastic behavior and is therefore thermodynamically and kinetically dependent [11]. From this viewpoint, the polymer surface can continuously restructure and reorient in response to different external factors such as atmosphere, solvent, and so on and might be inherently a nonequilibrium dynamic system. The guiding force for these structural changes is that the surface tends to decrease its free energy in a continuous way. In other terms, surface chemistry, reactivity, and aspect vary in function of environmental and processing conditions, influencing any desired modification and/or application of the related material even when bulk properties are considered [12].

In order to understand the application‐related modification of a polymer surface, one should first learn what the polymer surface is actually, how its properties are generally influenced, and what analytical methods are the most appropriate to study and understand. This chapter aims at providing a summary of experimental and theoretical concepts describing polymer surfaces near interfaces. It discusses the role of the different factors such as the surrounding environment in the surface properties and shows the multitude of analytical tools under different situations involving surfaces and interfaces.

1.2 The Surface of Polymers

1.2.1 Definition of a Polymer Surface

The word “surface” in its most general use includes the outermost or the uppermost layer/boundary of a physical object or space/area (http://www.wordreference.com/definition/surface). From the materials science viewpoint, the surface, defined as the frontier between two different media, is characterized by a certain thickness, reflecting a gradient of properties. With this respect, surface ever differs from the bulk of any material in terms of density, composition, or structure, and, even if it is present at very small fraction (by comparison to bulk), the surface governs any polymer properties, as being the first contact sets on. This statement remains true whatever the macroscopic material, including polycrystalline solids or polymers.

However, for polymer surfaces, the molecular length scale goes well above the angstrom scale (e.g. a typical end‐to‐end distance is about 10⁻⁶ m for a polymer of 10 000 monomer units and considering the random‐coil conformation [13]), and the term “small fraction” is broadly true. Herein, the connectivity, the entanglements and the interactions between polymer chains at the surface are built up for a surface thickness varying from several nanometers (for a layer in direct contact with other medium) up to several micrometers (for a crystalline morphology) [12]. Even though the interactions decrease upon increasing the distance, they remain the source of cohesion and determine the surface properties such as friction, adhesion, surface tension, and biological activity. Moreover, polymer chains have high degree of freedom (side‐group [methyl, hydroxyl, carbonyl, etc.] C–C rotation, segmental α‐process, and overall chain dynamics) and actual time and temperature‐dependent local or long‐range motions, making surfaces dynamic objects thereof [14] undergoing rearrangements upon changes into the surrounding phase(s): gas(es), liquid(s), or solid(s). Additionally, for a polymer macromolecule in the bulk, the interactions are similar in terms of type and force in...

Table of contents

• Cover
• Table of Contents
• Introduction
• 1 The Surface of Polymers
• Part I: Gas Phase Methods
• Part II: UV and Related Methods
• Part III: Chemical Methods
• Part IV: Applications
• Index
• End User License Agreement