Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHB-V) has not been used for demanding technical applications yet due to its limited mechanical properties, particularly its high brittleness. An appropriate route to overcome these limitations is the implementation of plasticizers in the PHB-V matrix via compounding. In this paper the use of different types of fatty acids esters as PHB-V plasticizers were investigated. The study describes how the difference in the fatty acid esters structure (mainly fatty acid hydrocarbon chain length) affects their plasticizing effect and thus the PHB-V ductility performance. The best impact properties of PHB-V compounds were obtained for oleic acid methyl ester, palmitic acid methyl ester or lauric acid ethylene glycol monoester. The increase of notched impact strength from 1.4 (for neat polymer) to 4.0-4.1 kJ/m 2 was observed. At the same time stiffness and strength of the polymer decreased but remain on a level sufficient for technical applications. Additional drawback of PHB-V materials is increasing the brittleness over time. Moreover this study shows that the use of oleic acid ethylene glycol monoester or stearic acid ethylene glycol monoester as plasticizers significantly reduces the increase of the brittleness of PHB-V over time. It is relevant that this drawback of PHB-V materials can be significantly improved by plasticizer addition.
New task-specific ionic liquids, hydroxy-functionalized 1methyl-3-alkylimidazolium hydroxides, were used as catalysts in the transesterification of rapeseed oil with methanol. In comparison to the well-described 1-methyl-3-butylimidazolium hydroxide [bmim]OH, the new ionic liquids show unexpectedly high catalytic activity.I nc ase of the ionicl iquid [glymim]OH, which is structurally similart og lycerol, the conversiono fr apeseed oil was nearly 100 %.Applications of ionic liquids( ILs), due to their unique properties, are the subject of al arge number of studies. In comparison to acidic and neutral ionic liquids, which have been widely described in the literature, reports describing the synthesis and use of basic ionic liquids are relatively limited. [1][2][3] Popular imidazolium ionic liquidsc ontaining BF 4 or PF 6 anions are characterized by low stabilityi na lkaline reaction media. The first stable basic IL 2,3-dimethylimidazolium hydroxide[ dmim]OH was described by Seddon et al. [4] In 2005 Ranu et al. described the synthesis of the now well-known basic ionic liquid 1methyl-3-butylimidazolium hydroxide [bmim]OH. [5] Both of these ionic liquids have strong basic character and are active in base-catalyzed reactions, in particulari nM ichael and Knoevenagel condensations. [6][7][8][9] Recently an immobilized form of [bmim]OH was also described. [10] As supports, CoFe 2 O 4 and SiO 2 /CoFe 2 O 4 magnetic nanoparticles were used.The properties of ionic liquidsc an be modified by the introductiono fv ariousf unctional groups. Such ionic liquidsa re known as task-specific ionic liquids (TSIL) or third-generation ionic liquids. ILs called "functionalized ionic liquids" combines the classic features of ionic liquidsa nd the specific activity. TSILs also include hydroxy-functionalized ionic liquids containing free OH groups. "Hydroxy" imidazolium ionic liquids[ HOpmim]BF 4 and [HOpmim]PF 6 were first described Branco et al. [11] The populari onic liquids [Rmim]X have been supplemented with strong polar and solvation properties. This meanst hat in some applications the "hydroxy" ionic liquidsc an replace conventional alcohols.H olbrey et al. described the synthesis of 1methyl-3-hydroxypropylimidazolium ionic liquids through the reactiono fp ropylene oxide with N-methylimidazole. [12] Un- [a] Dr.
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