Plasma treatment of PET films was carried out under argon, followed by exposure to an oxygen atmosphere. The films underwent considerable changes in surface composition and morphology, as demonstrated by contact angle measurements, FTIR‐ATR, AFM, and XPS. It was found that the surface acquired oxygen containing polar functional groups such as —C=O, —OH, and —OOH, which increased in number as the plasma treatment time increased. During storage, the treated films underwent significant surface reorganization, and both the time and temperature contributed to the increase in the contact angle. As revealed by AFM measurements, these changes were accompanied by an increase in roughness in the form of ridges. The ridges were observed to grow in height with increasing treatment time, although their spacing showed little evolution. A correlation among the observations obtained from various techniques was established, giving a comprehensive picture of the structure and dynamics of plasma‐treated PET surfaces. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 1083–1091, 2000

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Formation of stable and hydrophobic self-assembled monolayers (SAMs) on an oxidized copper (Cu) surface has been accomplished via reaction with 1H,1H,2H,2H-perfluorodecyldimethylchlorosilane (PFMS). The perfluoroalkyl SAMs showed sessile drop static contact angles of more than 125°for pure water and stability against exposure to boiling water, boiling nitric acid solution, and warm sodium hydroxide solution for up to 30 min. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared reflection/absorption spectroscopy (FT-IRRAS) data reveal a coordination of the PFMS silicon (Si) atom with a cuprate (CuO) molecule present on the oxidized copper substrate. The data give good evidence that the stability of the SAM film on the PFMS-modified oxidized Cu surface is largely due to the formation of a siloxy-copper (-Si-O-Cu-) bond via a condensation reaction between silanol (-Si-OH) and copper hydroxide (-CuOH). The extremely hydrophobic and stable SAMs on oxidized Cu could have useful applications in corrosion inhibition for micro/nanoelectronics and/or heat exchange surfaces exploiting dropwise condensation.

Zinc sulfide (ZnS) powders have been obtained by precipitation from homogeneous solutions of various zinc salt compounds, with S 2− as precipitating anion, formed by decomposition of thioacetamide. Spherical particles with a very narrow size distribution can be obtained by controlling the synthesis parameters. The particle sizes are influenced by the nature of the associated anion. For example, nanometer-sized ZnS particles are formed using acetate or acetylacetonate anions under acidic pH conditions, controlled by the addition of acetic acid. Although the nucleation is accelerated by the use of acetic acid, limited particle growth occurs because of the formation of complexes with zinc cations that lowers the concentration of free cations in the solution. Also, the complexing-attachment phenomena of the ZnS particles with acetate and acetylacetonate anions lead to the arrest of particle growth processes. The presence of complexed Zn 2+ species in the acidic solution is demonstrated both theoretically, using a model based on the calculations of the solubility isotherms of the soluble species, and by Fourier-transform infrared techniques. The nanostructured ZnS particles may provide a suitable semiconductor nanocluster material for optoelectronic applications as well as a phosphor suitable for application in flatpanel display technology.

Reactions of singly charged atomic nickel ions with several linear alkanes have been studied using an ion beam apparatus and ion cyclotron resonance spectroscopy (ICR). Results using deuterated compounds indicate that dehydrogenation is an important reaction which proceeds via a highly specific 1,4 process. ICR studies of the subsequent reactions of the NiC4H8+ ion formed from dehydrogenation of n-butane with Ni+ suggest that loss of H2 occurs by oxidative addition to the internal carbon-carbon bond followed by a (¡-hydrogen transfer to the metal. This intermediate can then either reductively eliminate an alkane or abstract another ß hydrogen and eliminate H2, forming what can be most simply described as a bisolefin complex.

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