The identification of peroxy‐features at polymer surfaces by ESCA

Abstract

A preliminary investigation of the identification of peroxy‐features at polymer surfaces by ESCA is described. Oxidation of a hydrocarbon polymer in the effluent of a singlet molecular oxygen generator, based on a microwave discharge in oxygen, produces surfaces rich in peroxy‐features. By comparison with experimental and theoretical studies of model systems these features can be identified in ESCA spectra by their characteristic O1s binding energies. The oxygen atoms in the peroxy‐linkage have essentially the same binding energy, which is within a narrow range of 534.0 eV for simple peroxides and hydroperoxides and a narrow range of 535.2 eV for peroxy‐features in more highly oxygenated environments; for example, peracids and peresters. Peroxy‐linkages decompose rather rapidly under the typical x‐ray flux used in the ESCA experiment.

Surface Enrichment in Equimolar Mixtures of Non‐Functionalized and Functionalized Imidazolium‐Based Ionic Liquids

“…This value is extraordinarily large and to the best of our knowledge oxygen with such a high binding energy is only described in polymers, e. g. 535.5 eV for peroxy-oxygens in dibenzoyl peroxide. [51] 2. 2 Im] + , two low-energy conformers (based on out-of-plane ether group orientations, see SI for detail) were identified.…”

XPS studies of in situ plasma-modified polymer surfaces

“…Numerous XPS studies have been done to gain insights into the chemistry of plasma-modified polymer surfaces [1][2][3][4][5][6][7][8][9][10][11][12]. A variety of gases were used in these studies, including argon, oxygen, nitrogen, ammonia, water, and combinations of the above.…”

Characterization of water vapor plasma‐modified polyimide

“…Included among the other systems studied are polypropylene and polystyrene surface modification in oxygen plasma, l3 poly (tetrafluoroethylene ) treated in air discharge, l4 and poly (ethylene terephthalate) treated in air discharge. 15 To determine the resulting surface chemistry, X-ray photoelectron spectroscopy has been used immediately following plasma surface modification 7,8,11,13,14,[16][17][18][19] as well as in conjunction with surface derivatization reactions following plasma treatment.4-6'9J0~20 Clark and Harrison2' even assembled a chart of core-level binding energies for common functionalities of interest in the study of polymers. The same as for a number of the studies on plasma surface modification, the aim of the work is to elucidate the effect of various plasma treatments on the adhesive properties of the polymer The literature contains a number of works that have studied water vapor p l a~m a .~~-~' Salvati et al32 proposed a mechanism that involves reactive decarboxylation/reduction followed by water chemisorption/functionalization for poly ( methyl methacrylate ) treated in a combination water vapor-argon plasma.…”