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Ring opening metathesis polymerization derived poly(norbornene) films and aggregates were crosslinked via photo chemically induced thiol-ene chemistry using a multifunctional thiol and the double bonds present in the polymer backbones. The presented method was illustrated by the description of a negative-toned photoresist formulation based on above mentioned ingredients.

Presently, commercially available lithium-ion batteries use graphite based anodes in combination with organic carbonate (e.g. Propylene Carbonate, PC, Ethylene Carbonate, EC) electrolytes. In this kind of Li-ion batteries the solid electrolyte intephase (SEI) formation process on the surface of graphite is crucial since it strongly influence the performances of the batteries systems [1]. It is known that the use of electrolyte additives (e.g. containing vinylene groups) improves the design of the resulting SEI on the graphite and leads to more efficient cycling of the material [2]. For that, several types of additives have been already studied and tested and intense research is now focused on the optimization of their design for a more effective film-forming efficiency. Ionic Liquids (ILs), room temperature molten salts typically showing a very low vapor pressure, high thermal stability, wide electrochemical windows and good conductivity at room and sub-room temperatures [3-4]. These properties make them very attractive candidates for the use as electrolytes in electrochemical devices such as batteries, particularly to increase the safety and the operative temperature range. So far, different types of ILs have been already used in combination with graphite electrodes with promising results [5-7]. However, only few reports studied the SEI formation process on graphite electrodes when ILs are used in the electrolytes as well as the contribution of additives to the SEI formation in such electrlytes [8]. Recently, we investigated the role of the additive Vinylene Carbonate (VC) in ILs-based electrolyte. The results of our studies indicated that when ultrapure ILs are used as electrolytes in combination with graphite electrodes, the need of additives in the electrolyte solution is strictly related to the film-forming ability of the ILs [9] themselves. For instance, in electrolyte solution based on the ultrapure ionic liquid N-butyl-N-methylpyrrolidinium bis(trifluoromethansulfonyl)imide (PYR14TFSI) the use of VC appears to be indispensable because such IL does not display film-forming ability. To the contrary, in electrolyte solution based on the ultrapure N-methyl-Npropylpyrrolidinium bis(fluorosulfonyl)imide (PYR13FSI) the presence of VC was not strictly required because this IL displays film-forming ability. In order to investigate the film-forming ability of PYR13FSI and the possibility of using this IL as additive or co-solvent in pure IL-based solutions, we prepare different mixture of PYR13FSI -PYR14TFSI with and without VC. These solutions have been used in combination with the graphite electrode and their influence on the specific capacity, the cycling efficiency and the cycling stability of the electrodes have been investigated. As example, Fig. 1 shows the cyclic voltammetry at 50 μV sec of graphite electrode in 0.3 M LiTFSI + PYR14TFSI + 5%wt. VC (A); 0.3 M LiTFSI + PYR14TFSI [50%] PYR13FSI [50%] + 5%wt. VC (B) and 0.3 M LiTFSI + PYR13FSI + 5%wt. VC (C). Also the influence of two different Lithium salt (Lithium bis(trifluoromethansulfonyl)imide, LiTFSI and Lithium exafluophosphate, LiPF6) on the performance of graphite electrode in the mixtures of PYR13FSI PYR14TFSI has been investigated. These studies clearly evidence that the Li-salt strongly influence the performance of graphite electrode in combination with ILs-based solutions.

Polymer/ionic liquid composites were investigated as solvent-free electrolytes for lithium batteries. Ternary electrolytes based upon poly(ethylene oxide), an ionic liquid and a conducting salt were UV crosslinked with benzophenone as the photoinitiator. Crosslinking leads to an increase in mechanical stability of the PEO composites. This straight-forward process provides a way to increase the content of ionic liquid and thus to raise ionic conductivity without loss of mechanical stability. Impedance measurements showed that the ionic conductivity of the composites is not affected by the UV curing process. Moreover, the UV curing process causes a decrease in the degree of crystallinity in the PEO composites which contributes to an increase in ionic conductivity. The present work is related to safety issues of lithium batteries.

We synthesized two carminic acid (7-alpha-d-glucopyranosyl-9,10-dihydro-3,5,6,8-tetrahydroxy-1-methyl-9,10-dioxo-2-anthracene carboxlic acid, CA)-GnRH conjugates to be used as a model for potential photoactive targeted compounds. CA was conjugated to the epsilon-amino group of [d-Lys(6)]GnRH through its carboxylic moiety or via a beta-alanine spacer (beta-ala). Redox potentials of CA and its conjugates were determined. We used electron spin resonance (ESR) and spin trapping techniques to study the light-stimulated redox properties of CA and its CA-GnRH conjugates. Upon irradiation, the compounds stimulated the formation of reactive oxygen species (ROS), that is, singlet oxygen ((1)O(2)) and oxygen radicals (O(2)(-*) and OH(*)). Both conjugates exhibited higher ROS production than the non-conjugated CA. The bioactivity properties of the CA conjugates and the parent peptide, [d-Lys(6)]GnRH, were tested on primary rat pituitary cells. We found that the conjugates preserved the bioactivity of GnRH as illustrated by their capability to induce ERK phosphorylation and LH release.

The solid electrolyte interphase (SEI) formation on commercial graphite, KS6 TIMCAL, in two different ionic liquids, N-methyl-N-butyl pyrrolidinium bis(trifluoromethansulfonyl)imide (PYR14TFSI) and N-methyl-N-propylpyrrolidinium bis(fluorosulfonyl)imide (PYR13FSI) has been investigated. The role of the Vinylene Carbonate (VC) addition to the ionic liquid-based electrolyte has also been studied. To monitor the change at the electrode/electrolyte (IL) interface during the SEI formation, we took advantage of the in situ Fourier transform infrared spectroscopy (FTIRS). The results of the investigation performed at room temperature are presented in this manuscript.

The thiol-ene reaction is a established photoreaction of multifunctional thiols and enes. Virtually any type of ene will participate in a free radical polymerisation process with a thiol. An advantage over many other photochemical reactions is that the reaction proceeds almost as rapidly in ambient conditions as in inert atmosphere. In this work we introduce the UV-crosslinking of polynorbornenes made by ring opening metathesis polymerization making use of the residual double bond in the polymer backbone. The crosslinking experiments were done in thin films and were followed by FTIR measurements, to proof the accessibility of double-bonds in the polymers for the addition of the thiols. As a result of these pre-experiments we created flexible and light transmitting films. To further increase the scope of this reaction, amphiphilic block copolymers were prepared and used to form block copolymer micelles in a selective solvent, which were subsequently crosslinked with pentaerythritol tetra(3-mercaptopropionate) (PETMP). FT-IR, DLS and SEM-measurements were used to prove the successful crosslinking and thus nanoparticle formation.