Many well-established methods for studying the degradation of brominated flame retardants are not useful when working with polymeric and water insoluble species. An example for this specific class of flame retardants is PolyFR (polymeric flame retardant; CAS No 1195978-93-8), which is used as a substituent for hexabromocyclododecane. Although it has been on the market for two years now, almost no information is available about its long time behavior in the environment. Within this study, we focus on how to determine a possible degradation of both pure PolyFR as well as PolyFR in the final insulation product, expanded polystyrene foam. Therefore, we chose UV radiation followed by analyses of the total bromine content at different time points via ICP-MS and identified possible degradation products such as 2,4,6-tribromophenol through LC-MS. These results were then linked with measurements of the adsorbable organically bound bromine and total organic carbon in order to estimate their concentrations. With respect to the obtained H NMR, GPC, and contact angle results, the possibility for further degradation was discussed, as UV irradiation can influence the decomposition of molecules in combination with other environmental factors like biodegradation.

Nonspecific adsorption of proteins is a challenging problem for the development of biocompatible materials, as well as for antifouling and fouling-release coatings, for instance for the marine industry. The concept of preparing amphiphilic systems based on low surface energy hydrophobic materials via their hydrophilic modification is being widely pursued. This work describes a novel two-step route for the preparation of interpenetrating polymer networks of otherwise incompatible poly(dimethylsiloxane) and zwitterionic polymers. Changes in surface hydrophilicity as well as surface charge at different pH values are investigated. Characterization using atomic force microscopy provides thorough insight into surface changes upon hydrophilic modification. Protein fouling of the materials is assessed using fibrinogen as a model protein.

Hydrophobic association and stimuli-responsiveness is a powerful tool towards water-based adhesives with strongly improved properties, which is demonstrated based on the example of hydrophobically modified alkali-soluble latexes (HASE) with modulated association. Their rheological properties are highly tunable due to the hydrophobic domains that act as physical crosslinking sites of adjustable interaction strength. Ethanol, propanol, and butanol are used as water-soluble model additives with different hydrophobicity in order to specifically target the association sites and impact the viscoelastic properties and stimuli-responsiveness. The rheological and mechanical property response upon dilution with water can be tailored, and dilution-resistant or even dilution-thickening systems are obtained. The investigations are of high importance for water-based adhesives, as our findings provide insight into general structure-property relationships to improve their setting behavior, especially upon contact with wet substrates.

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The synthesis of new polysiloxanes was performed via hydrosilylation reactions of polymethylhydrosiloxane with 4-allyl-1-methoxybenzene and 4-allyl-1,2-dimethoxybenzene in the presence of Karstedt's catalyst {Pt 2 [(VinSiMe 2 ) 2 O] 3 } and platinum hydrochloric acid (0.1M solution in tetrahydrofuran). The hydrosilylation reactions were carried out at 608C. The molar ratio of BSiÀ ÀH groups to the allylic compound was 1 : 1.2. The synthesized oligomers were characterized with 1 H-NMR, Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetry, and gel permeation chromatography. In the presence of platinum hydrochloric acid, not all active BSiÀ ÀH bonds took part in hydrosilylation, and because of this, gelation took place and the molecular masses of the extracted parts increased 7-8 times; in contrast to this, in the presence of Karstedt's catalyst, all active BSiÀ ÀH bonds participated in hydrosilylation, and an increase in the molecular masses did not occurs. The influence of substituted methoxy groups on the glass-transition temperatures was studied.