Photolabile carboxylic acid protected terpolymers for surface patterning. Part 1: Polymer synthesis and film...

We present the synthesis and characterization of a series of photolabile phenacyl derivative polymers and their subsequent thin film preparation. These systems are composed of up to three methacrylate units: a photolabile component including a p-methoxyphenacyl moiety which after selective irradiation (UV/laser) can provide free carboxylic groups in specific areas for further modification; an anchoring unit, trimethoxysiloxane or glycidyl methacrylate derivative, which allows the covalent attachment of the polymer to the substrate; and a spacer, methyl methacrylate or styrene, which in the appropriate proportion ensures the formation of films with good quality. Structural and thermal properties of these materials have been analyzed by means of NMR, FTIR, elemental analysis, UV, gel permeation chromatography, differental scanning calorimetry, and thermogravimetric analysis. The polymers have been subsequently processed by spin coating to render ultrathin films (<50 nm). Topographic and structural characterization studies of the films have been carried out with atomic force microscopy, contact angle measurements, and X-ray photoelectron spectroscopy. The extent of the substrate attachment of the polymers depending on the nature of the anchoring groups have been studied by ellipsometry and FTIR.