Dynamics in adsorbed homopolymer layers: Understanding complexity from simple starting points

Now more than ever, smart material interfaces in a variety of applications demand control over complex interfacial processes, often involving adsorbed polymers. To this end, this opinion article addresses the dynamic complexity in homopolymer layers adsorbed at liquid–solid interfaces, summarizing some of the simplest examples and examining the potential impact of specific complicating mechanisms: The distinction between diffusion limited (in free solution) and surface-controlled chain release is made, and then for the latter, several different cases of single-exponential desorption, self-exchange, and displacement are compared: Though the systems present great chemical variety, they have either a limited number of or a weak energy of segment–surface contacts. Increasing the strength and/or numbers of these contacts complicates dynamics, as does increasing molecular weight which can introduce chain pinning.