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In this work, the modification of ethylene-co-vinyl alcohol (EVOH) copolymer with a coumarin derivative, 7- (hydroxyethoxy)-4-methyl coumarin (HEOMC), has been performed through the incorporation of different reactive groups, p-nitrophenyl chloroformate, succinic anhydride and phthalic anhydride as different linkers between coumarin and EVOH with the aim to obtain photo-responsive materials with improved protein absorption resistance. After purification, the modification degree was calculated by nuclear magnetic resonance and ultraviolet- visible spectroscopy. The thermal properties revealed the crystallinity loss and higher maximum degradation temperatures when EVOH is modified with coumarin derivative. Copolymers were successfully photocrosslinked through the photo-responsive behavior of coumarin moieties. The micro-hardness test shown an increase of the mechanical performance due to the coumarin presence. The water contact angle measurements revealed that while coumarin-modified EVOH copolymers present a higher hydrophilic behavior than EVOH, the photo-dimerization process mainly leads to slightly deviations on the surface wettability of neat EVOH. Finally, the absorption of bovine serum albumin onto the surface of the coumarin-modified materials revealed enhanced antifouling properties, particularly after the photo-crosslinked process. Therefore, the introduction of coumarin through different chain extenders leads to functional materials with tunable photo-responsive performance and protein absorption resistance., Authors thank Spanish Ministry of Science and Innovation (Projects MAT2016-78437-R MAT2017-88123-P), the Agencia Estatal de Investigación (AEI, Spain) and Fondo Europeo de Desarrollo Regional (FEDER, EU). M.P.A. and L.P. acknowledge the Juan de la Cierva (FJCI- 2014-20630) and Ramon y Cajal (RYC-2014-15595) contracts from the MINECO, respectively. A.C. also acknowledges his FPU fellowship FPU18/01776.

Coumarin and poly-ε-(caprolactone) diol (PCL)-based polyurethanes (PUs), were reinforced with modified silica nanoparticles (mSiNPs), in which a novel coumarin molecule was synthetized. The behavior as photo-responsive coatings of these materials was studied. The silica nanoparticles (SiNPs) modification was analyzed by infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and UV spectroscopy. The yield of photo-crosslinking in nanocomposites loaded with mSiNPs was studied by UV–vis spectroscopy, which showed higher conversion degree than nanocomposites with unmodified SiNPs and non-reinforced PUs. The dispersion of mSiNPs on segregated microdomains was observed by transmission electron microscopy (TEM). The presence of coumarin grafted on the SiNPs surface (mSiNPs) leads to an improvement on the thermal stability of PU matrix. Meanwhile, they were able to maintain the mechanical performance before and after the irradiation process mainly due to the improved nanofiller-matrix interaction. Contact angle measurements were also assayed to study the hydrophobicity changes on the surface of modified nanocomposites. The observed phase segregation was associated with the mechanical and thermal properties of the materials and the photo-crosslinking of coumarin moieties bring to the final material high responsiveness to be employed as photo-switchable coatings., Authors thank Spanish Ministry of Economy, Industry and Competitiveness, MINEICO (MAT2013-48059-C2-1-R) and Regional Government of Madrid (S2013/MIT-2862). M.P.A. and L.P. acknowledge the Juan de la Cierva (FJCI-2014-20630) and Ramon y Cajal (RYC- 2014-15595) contracts from the MINEICO, respectively. Authors specially thank Dr. Emilio Rayón and Prof. Juan López Martínez (Universitat Politècnica de València, Spain) for TEM analysis

Enzymatic polymerization has a large potential as an environmentally friendly synthetic process. Lipase is a renewable catalyst with high catalytic activity from which it is possible to develop a versatile method for the production of sustainable polyurethanes. In this work oligomeric PCL-diol was synthesized using biocatalysis with immobilized Yarrowia lipolytica lipase (YLL) and diethyleneglycol as initiator. Then, two different linear polyurethanes were prepared. One was obtained directly from the previous synthesized PCL-diol and hexamethylene diisocyanate, named PU, and the other one has been obtained by incorporating L-lysine amino acid as end group (lys-PU). PU and lys-PU disintegration under composting conditions was evaluated. The influence of the presence of L-lysine on the disintegration performance of PU was studied by evaluating the disintegration degree, monitoring the weight loss. Structural and morphological changes were followed by Fourier transformed infrared spectroscopy (FTIR) and by scanning electron microscopy (SEM)., Authors thank Spanish Ministry of Economy, Industry and Competitiveness, MINEICO, ( and MAT2013-48059-C2-1-R MAT2017-88123-P) cofinanced with FEDER funds, Regional Government of Madrid (S2013/MIT-2862) and Consejo Nacional de Ciencia y Tecnología (CONACYT, Grant 153922) for the financial support. M.P. Arrieta and L. Peponi acknowledge the Juan de la Cierva (FJCI-2014-20630) and Ramon y Cajal (RYC-2014-15595) contracts from the MINECO, respectively. Authors also acknowledge Prof. Juan López Martínez (Universitat Politécnica de Valencia, Spain) for his assistance with colorimetric measurements.