Water-soluble photoresins based on polymeric azo compounds

Cyclodextrins in polymer synthesis: photocrosslinkable films via free radical copolymerization of methylated β-cyclodextrin-complexed styrene with sodium 4-(acrylamido)-phenyldiazosulfonate in aqueous medium

“…The reason for this can be found not only in the large difference in solubility of the two comonomers, but also in the increasing effect of the azo compound as a radical scavenger [20] at higher temperatures and prolonged reaction times. However, for the intended use of diazosulfonate polymers as fully water-soluble photo resins [21], a diazosulfonate content of at least 20 mol% and molar masses suf ciently high for good lm-forming properties and high mechanical stability are required.…”

Imagewise Structuring of Diazosulfonate Polymer Films by UV Light and Laser Irradiation - A Comparison

“…A copolymer P1 of MMA and sodium methacrylamido-4-phenyldiazosulfonate 1 with a feed ratio 80/20 and synthesized via free radical polymerization [9] has been used in this study (Scheme 2). This polymer of a molar mass of about 16 000 g/mol and 18 mol-% incorporated azo monomer (as determined by UV spectroscopy) is fully soluble in mixtures of water and methanol.…”

“…[9] The monomers are obtained combining sodium 4-aminophenyldiazosulfonate with (meth)acryloyl chloride. Methyl methacrylate (MMA) (Fluka) and hydroxyethyl methacrylate (HEMA) were purified by passing them through a basic aluminium oxide column to remove the stabilizer and distilling afterwards.…”

“…[9,10] For P1, 29 mmol (3.1 mL) methyl methacrylate and 7.2 mmol (2.1 g) 1 were polymerized using 1.8 mmol (0.30 g) 2,29-azoisobutyronitrile in a dioxane/water (4/1) solution at 70 8C for 17 h. After evaporation of the solvent, the polymer was dissolved in 80 mL methanol and precipitated in 1 L diethyl ether. After filtration the product was dried for 24 h in vacuum at 50 8C.…”

“…This irradiation time is long enough for complete decomposition of all sulfonate groups as verified in independent measurements. [9] Contact angles of water were measured by the sessile drop method using a conventional goniometer device (Krüss GmbH). The liquid drop was deposited on a given solid surface and a tangent was drawn at the three-phase contact line of the drop at its base.…”