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Starch is one of the most commonly available natural polymers which are obtained from agrosources. It is renewable and abundant in nature. Unfortunately due to its poor mechanical properties and hygroscopic nature, there are some strong limitations to the development of starch-based products. Usually blends of starch are prepared and plasticized with glycerol to improve some of its properties. In this study, lignin was extracted from hazelnut shells and investigated as a potential additive for starch biofilms. The structural characterization of hazelnut lignin was performed by employing UV spectroscopy and Fourier transform infrared (FTIR) spectroscopy. Lignin was blended with corn starch in different ratios to obtain biofilms. Mechanical and thermal properties of the biofilms were enhanced as the lignin amount was increased in the formulations. Water absorption tests were performed at pH 2.0, 4.0, and 6.0. The percent swelling values of the starch/lignin films increased as pH increased. Also, the biofilm exhibiting the best properties was chosen for the drug release studies. Biofilms showed a fast ciprofloxacin (CPF) release within an hour and then the drug release rate decreased. A pH dependent drug release mechanism was also observed according to Koshner-Peppas model. The drug release increased with a decrease in pH.

The synthesis of fluorinated polymers via efficient routes along with mild experimental conditions is always desirable in terms of synthetic polymer chemistry. In this work, a straightforward method for fluorinated polythioether synthesis was developed. A commercially available electron-deficient alkyne compound, namely 4,4,4-trifluoro-2-butynoate (1), linked to both trifluoromethyl (CF 3 ) and ester units was polymerized with various dithiols by using 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) as a catalyst at room temperature, yielding CF 3 -substituted polythioethers (CF 3polythioethers). Unlike common polymerization methods (anionic and radical) described in the literature, which include harsh conditions to produce CF 3 -substituted polymers, the synthetic methodology followed in this study offers mild conditions, and CF 3 -polythioethers with high molecular weights (M w , up to 21.1 kDa in 1 min and up to 42.5 kDa in 1 h) were obtained in high yields in reasonably short durations. The judicious combination of polythioether chemistry with a rapid polymerization method was introduced in this study to open a way for the development of novel fluorinated polymeric materials.

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Direct preparation of coatings from neat vegetable oils without any pretreatment or modification is an elegant way of demonstrating the potential of renewable sources and it is also in line with the principles of Green Chemistry.In this work, photocured coatings were prepared from tung oil (TO), hazelnut oil (HN), and isosorbide. First, a dithiol derivative of isosorbide (ISTMP) was synthesized and then mixed with TO, HN, and a cationic photoinitiator. For comparison, formulations were also prepared by using two different commercial thiol compounds. Coating formulations were applied onto glass substrates and cured under UV light where oxidative polymerization and photoinitiated thiol-ene addition reactions took place concomitantly. Double bond conversion percentages, thermal degradation properties, water contact angles, and surface hardness of the coatings were determined. Furthermore, a model reaction between ISTMP and oleic acid was performed to prove that ISTMP reacts with the fatty acid. ISTMP containing formulation displayed a fast initial double bond conversion and its water contact angle value was found as 88 ± 3 . Rigid and thermally stable isosorbide ring improved both the thermal properties and the surface hardness of the coatings.

The preparation of multifunctional, smart, and environmentally friendly coating materials is an innovative way to answer the needs in both today’s and future technologies of coatings. In this work, antibacterial and environmentally friendly photocured coatings were prepared via a thiol–ene photopolymerization technique. First, with the aim to reduce the carbon footprint of the petroleum-based monomers, a greener alternative, isosorbide diallyl ether (IDE), was synthesized. Then a polymerizable fluorinated quaternary phosphonium salt (PFQPS) was synthesized to render the coatings antibacterial. PFQPS was added in different amounts (1%, 3%, 5%, and 10%) to the IDE-based thiol–ene-based formulations, and its effect on the thermal, mechanical, and optical properties were investigated. The prepared coatings exhibited exceptional antibacterial activity against E. coli and S. aureus. When the concentration of the PFQPS was 10%, the zone inhibition diameters were found as 82 ± 5 and 18 ± 1.9 for E. coli and S. aureus, respectively.