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001-es BibID:	BIBFORM126565
035-os BibID:	(Scopus)85208057185 (WoS)001353478400001
Első szerző:	Benea, Ioana Cristina
Cím:	Efficient biotransformation of biobased raw materials into novel polyesters/polyesteramides; comparative investigation of enzymatic synthesis of block and random copolymers and terpolymers / Benea, Ioana Cristina; D¡aescu, Diana; Todea, Anamaria; Nagy, Lajos; Keki, Sandor; Paușescu, Iulia; Pellis, Alessandro; Peter, Francisc
Dátum:	2024
ISSN:	0141-8130
Megjegyzések:	Within the context of paving the way for a sustainable bioeconomy, there is a strong emphasis on utilizing bio-based raw materials as substitutes for fossil fuels in the production of polymers. When designing the synthesis of novel polymeric materials from bio-based building blocks, a promising green approach consists in utilizing enzymes as biocatalysts. This aspect is particularly important when aiming to obtain products from the class of polyesters and polyesteramides with biocompatible and biodegradable properties, as enzymes facilitate the synthesis of polymers that align closely with biological systems. Lipases have been proven to be very effective in the synthesis of polymers, particularly in the ring-opening polymerization of ?-caprolactone. Considering the possibility of performing the copolymerization of ?-caprolactone for obtaining random and block structures, this is the first comparative study of the enzymatic polymer synthesis utilizing an innovative approach of combining ring-opening polymerization with polycondensation. Terpolymers derived from ?-caprolactone and dimethyl itaconate or dimethyl adipate with either 1,8-octanediol or 1,8-octanediamine were obtained at 85 C in a solventless systems, yielding products with a copolymer content of >85 % and weight-average molecular weight (Mw) up to 40,000 Da. The thermal properties and biodegradation behavior of the synthetized terpolymers were assessed.4
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk Biocatalysis Block polymers Lipase Polyester Polyesteramide Random polymers
Megjelenés:	International Journal Of Biological Macromolecules. - 282 (2024), p. 1-17. -
További szerzők:	Dăescu, Diana Todea, Anamaria Nagy Lajos (1979-) (vegyész) Kéki Sándor (1964-) (polimer kémikus) Pausescu, Iulia Pellis, Alessandro Péter, Francisc
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001-es BibID:	BIBFORM115360
035-os BibID:	(WoS)001070979000001 (Scopus)85168104200
Első szerző:	Bîtcan, Ioan
Cím:	One-pot green synthesis and characterization of novel furan-based oligoesters / Ioan Bîtcan, Alessandro Pellis, Andreea Petrovici, Diana-Maria Dreavă, Iulia Păușescu, Francisc Peter, Lajos Nagy, Sándor Kéki, Lucia Gardossi, Anamaria Todea
Dátum:	2023
ISSN:	2352-5541
Megjegyzések:	The synthesis of bio-based poly(5-hydroxymethyl-2-furancarboxylate-co-ricinoleate) was investigated either from ricinoleic acid and 5-hydroxymethyl-2-furancarboxylic acid or directly from castor oil by green biocatalytic pathways. The reactions were carried out using commercially available native and immobilized hydrolases. The reactions were performed either in the absence of solvent or in different organic solvents or ionic liquids at various molar ratios and temperatures up to 80 ?C. The lipase from Pseudomonas stutzeri showed the highest catalytic efficiency at 50 ?C in t-butanol. To increase the sustainability of the process, in the next step, an original "onepot" system consisting of two consecutive reactions catalyzed by the same enzyme was developed. Ricinoleic acid, obtained by in-situ hydrolysis of castor oil, was used together with 5-hydroxymethyl-2-furancarboxylic acid as raw material for the oligoester synthesis at 100 mbar pressure in a solventless reaction system, yielding a product with average molecular weight of about 5800 gmol-1, in optimized conditions. The insertion of 5-hydroxymethyl-2-furancarboxylic acid units into the ricinoleic acid estolide backbone was demonstrated by MALDI-TOF MS and 2D NMR analysis. The thermal properties of the resulting products were evaluated by TG and DSC.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk Ricinoleic acid 5-Hydroxymethyl-2-furancarboxylic acid Enzymatic polymerization Biocatalytic one-pot synthesis
Megjelenés:	Sustainable Chemistry and Pharmacy. - 35 (2023), p. 101229-101243. -
További szerzők:	Pellis, Alessandro Petrovici Andrea Dreava, Diana-Maria Pausescu, Iulia Péter, Francisc Nagy Lajos Kéki Sándor (1964-) (polimer kémikus) Gardossi, Lucia Todea, Anamaria
Pályázati támogatás:	PN-III-P1-1.1-TE-2019-1573 Egyéb
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM104069
035-os BibID:	(WoS)000489104300028 (Scopus)85071906261
Első szerző:	Todea, Annamaria
Cím:	Biodegradable Oligoesters of epsilon-Caprolactone and 5-Hydroxymethyl-2-Furancarboxylic Acid Synthesized by Immobilized Lipases / Anamaria Todea, Ioan Bîtcan, Diana Aparaschivei, Iulia Păuşescu, Valentin Badea, Francisc Péter, Vasile Daniel Gherman, Gerlinde Rusu, Lajos Nagy, Sándor Kéki
Dátum:	2019
ISSN:	2073-4360
Megjegyzések:	Following the latest developments, bio-based polyesters, obtained from renewable raw materials, mainly carbohydrates, can be competitive for the fossil-based equivalents in various industries. In particular, the furan containing monomers are valuable alternatives for the synthesis of various new biomaterials, applicable in food additive, pharmaceutical and medical field. The utilization of lipases as biocatalysts for the synthesis of such polymeric compounds can overcome the disadvantages of high temperatures and metal catalysts, used by the chemical route. In this work, the enzymatic synthesis of new copolymers of ?-caprolactone and 5-hydroxymethyl-2-furancarboxylic acid has been investigated, using commercially available immobilized lipases from Candida antarctica B. The reactions were carried out in solvent-less systems, at temperatures up to 80 C. The structural analysis by MALDI TOF-MS, NMR, and FT-IR spectroscopy confirmed the formation of cyclic and linear oligoesters, with maximal polymerization degree of 24 and narrow molecular weight distribution (dispersity about 1.1). The operational stability of the biocatalyst was explored during several reuses, while thermal analysis (TG and DSC) indicated a lower thermal stability and higher melting point of the new products, compared to the poly(epsilon-caprolactone) homopolymer. The presence of the heterocyclic structure in the polymeric chain has promoted both the lipase-catalyzed degradation and the microbial degradation. Although, poly(epsilon-caprolactone) is a valuable biocompatible polymer with important therapeutic applications, some drawbacks such as low hydrophilicity, low melting point, and relatively slow biodegradability impeded its extensive utilization. In this regard the newly synthesized furan-based oligoesters could represent a "green" improvement route.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk copolymerization renewable oligoester lipase furan-based epsilon-caprolactone
Megjelenés:	Polymers. - 11 : 9 (2019), p. 1-17. -
További szerzők:	Bîtcan, Ioan Aparaschivei, Diana Pausescu, Iulia Badea, Valentin Francisc Péter Gherman, Vasile Daniel Rusu, Gerlinde Nagy Lajos (1979-) (vegyész) Kéki Sándor (1964-) (polimer kémikus)
Pályázati támogatás:	GINOP-2.3.3-15-2016-00021 GINOP
Internet cím:	DOI Intézményi repozitóriumban (DEA) tárolt változat
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