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BackgroundPhosphorus-containing high performance polymers have aroused wide interest, mainly due to good mechanical properties and their excellent fire resistance. The flexibility of synthetic polyphosphoesters allows the development of polymers in order to obtain solid polymer electrolytes for rechargeable lithium batteries based on solid films with superior fire resistance.ResultsNovel linear Phosphonate-PEG polymers were synthesized by solution polycondensation of 4-chlorophenyldichlorophosphonate as a linking agent and poly(ethylene glycol)s with different molecular weights in the presence of triethylamine or 1-methylimidazole as acid scavenger. The yields were between 54% and 88% and inherent viscosity between 0.18-0.48 dl/g. Molar masses, Mn were about 26300 g/mol for polyphosphonates with PEG 2000 and 4600 g/mol for polyphosphonates with PEG 200. The LOI values for these polymers and membranes are in the range of 26–29. The membranes based on polyphosphonate with PEG 200 and 2000 showed conductivity between 6 × 10-8 S.cm-1 and 6 × 10-7 S.cm-1 at room temperature and total ionic transference number between 0.87- 0.96. The evolution of conductivity vs. temperature is linear.Conclusions1-methylimidazole was found to be better HCl scavenger than triethylamine, and allowed higher yields and more eco-friendly synthesis of the Phosphonate-PEG polymers for SPE. These polymers and membranes based on these polymers showed good LOI values and indicate an improvement of the safety of lithium batteries. The membranes present conductivities around 6 × 10-7 S.cm-1at room temperature and total ionic transference number is higher for membranes based on polymers with high EG unit content. Best results yield 88%, inherent viscosities 0.48 dl/g and Mn 26000 were obtained with 1-methylimidazole and PEG 2000. These membranes based on these polymers showed good LOI values (in the range 26-29%) and indicate an improvement of the safety of lithium batteries.

ABSTRACT:The curable formulations containing monomer-diacrylate, photoinitiator-p-methoxybenzoyldiphenylphosphine oxide/benzyldimethylketal, additive reactive-triethylamine, and inorganic thermoresistant pigments-white, red, green, and blue were cured by UV exposure films. A series of experiments was carried out to investigate the relationship between the particle size distribution of the inorganic pigment and the colorimetric and mechanical properties of the UV acrylic curable coatings. Pendulum hardness and appearance of the films depend on the content and particle size distribution of the pigment. Optimal particle size distribution and pigment content were established to obtain the best films concerning their pendulum hardness and chromatic parameters.

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The role and enlarged importance of ionic liquids (ILs) in chemical reactions were already exhaustively demonstrated. The aim of this review is to promote the family of the phosphonium‐based ILs used as reagents and catalysts, which gained increased interest in the last decade. The common and beneficial properties of ILs refer to their negligible vapour pressure, non‐toxicity, reusability, and high thermal stability. Therefore, phosphonium‐based ionic liquids are used successfully as catalysts and reagents in many chemical reactions, and additionally allow the syntheses in mild reaction conditions. Phosphonium ILs have proved their catalytic efficiency in many reactions such as epoxidation of olefins and allylic alcohol, in synthesis of alpha‐aminophosphonates, beta‐ketophosphonates, nitrogen‐containing bisphosphonates, the Michaelis‐Arbuzov reactions, esterification, coupling reaction, aromatic chlorination, dehydrogenation. The major advantage of phosphonium‐based ILs used as catalysts is that they can be reused with only little loss of catalytic activity. Phosphonium ILs revealed their potential as Wittig reagents, halogenation reagents for bromination and bromo‐chlorination reactions with alkenes and alkynes, as monomer and as initiator in frontal polymerization of acrylates. From the literature data, it can be concluded that due to their structure and physical‐chemical properties phosphonium ILs can be tailored function of their purpose.