Buckling Instabilities in Polymer Brush Surfaces via Postpolymerization Modification

Abstract

We report a simple route to engineer ultrathin polymer brush surfaces with wrinkled morphologies using post-polymerization modification (PPM), where the length scale of the buckled features can be tuned from hundreds of nanometers to one micrometer using PPM reaction time. We show that partial crosslinking of the outer layer of the polymer brush under poor solvent conditions is critical to obtain wrinkled morphologies upon swelling. Characterization of the PPM kinetics and swelling behavior via ellipsometry and the through-thickness composition profile via time-of-flight secondary ion mass spectroscopy (ToF-SIMS) provided keys insight into parameters influencing the buckling behavior.

Rapid, Template‐Less Patterning of Polymeric Interfaces for Controlled Wettability via in Situ Heterogeneous Photopolymerizations

“…The work of Guo et al. employed a post‐polymerization approach to create topographical features which resulted from stress‐instability in thin films of polymer brushes . With this methodology, polymer brushes were selectively cross‐linked near the brush/air interface by post‐modification in poor solvents, resulting in surfaces with wrinkle morphology.…”

“…Therefore, lithography is quite limited when considering applications where a large surface area with sub‐micron or nanoscale topology is needed, as it is not suited for scale‐up. Recently, some researchers have demonstrated how polymerization‐induced shrinkage and polymerization stress can be exploited to drive the formation of surface features . The work of Guo et al.…”

Understanding the chlorination mechanism and the chlorine-induced separation performance evolution of polypiperazine-amide nanofiltration membrane

“…The chlorine-induced morphology changes might be explained by the enhanced ductility of the PPA separating layer after chlorination due to the breakage of hydrogen bonds between polymer chains as confirmed by the ATR-FTIR measurement (Fig. 4) [18,[33][34]. After regeneration, some of the -NCl groups were reduced to -NH groups and thus new hydrogen bonds formed leading to the morphology recover.…”

Helium Ion Microscopy with Secondary Ion Mass Spectrometry (HIM-SIMS) for the analysis and quantitation of polyolefins

“…[2][3][4][5] As such, research has primarily been focused on characterization of copolymers and polymer blends using ToF-SIMS. [6][7][8][9][10][11] ToF-SIMS has been used to investigate surface chemistry, interfaces, microscopic phases, and to quantitatively map surface specific polymers in blends including styrene-methyl methacrylate random copolymers, ethylene-propylene-diene terpolymers, and polypropylene/ethylene-propylene copolymer blends [12][13][14][15] as well as to determine the molecular weight for a variety of polymers including PE, PP, and polystyrene (PS). 16 The possibility to analyze and distinguish polymers in a blend with nanosized structures becomes increasingly important as properties and performance of such materials can depend on the interfacial segregation, phase separation, and phase coarsening, which can vary in size down to tens of nanometers.…”