Surface and interfacial segregation of polyethersulfone deuterated chain ends determined by neutron reflectivity

ABSTRACT The surface localization of polymer chain ends has been shown to be an effective method for surface composition control in amorphous polymer films. This work determines chain end distribution in thin polyethersulfone (PESU) films end‐capped with deuterated compounds of varying size and composition. Neutron reflectivity revealed the preferential localization of chain ends to the PESU‐air interface, independent of chain end identity. The length scale of the chain end concentration gradient was determined to differ from that predicted for flexible chain polymers. Atomic force microscopy and contact angle analysis demonstrated that chain end localization allows for improved control of nanoscale and macroscale surface properties of PESU films. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 293–301 Neutron reflectivity analysis of thin films of polyether sulfone with deuterated end groups of different composition shows chain end surface segregation scaling with the radius of gyration (Rg). DMT modulus, adhesion, and surface hydrophobicity are determined by chain end composition. The preferential localization of a functionalized polymer chain end (thermodynamic process) may allow for more precise and sustained control of polymer surfaces than those created by kinetic processes.