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Journal of Renewable Materials 2023年第6期11卷 2823-2848页

作者： elham azadeh Antonio Pizzi Christine Gerardin-Charbonnier Philippe Gerardin LERMAB Faculty of Science and TechnologyUniversity of LorraineVandoeuvre les Nancy54506France LERMAB University of LorraineEpinal88051France

Non-isocyanate polyurethane(NIPU)foams from a commercial hydrolysable tannin extract,chestnut wood tannin extract,have been prepared to determine what chemical species and products are taking part in the reactions *** method is based on two main steps:the reaction with dimethyl carbonate and the formation of urethane bonds by further reaction of the carbonated tannin with a diamine-like hexamethylene *** hydroxyl groups on the tannin polyphenols and on the carbohydrates intimately linked with it and part of a hydrolysable tannin are the groups involved in these *** carbohydrate skeleton of the hydrolysable tannin is also able to participate through its hydroxyl groups to the same two reactions rendering the whole molecular complex able to react to form *** analysis by Matrix-Assisted Laser Desorption Ionization(MALDI-TOF)mass spectrometry and 13C Nuclear Magnetic Resonance(13C NMR)to further investigate the reaction mechanisms involved revealed the unsuspected complexity of chestnut hydrolysable tannin,with different fragments reacting in different manners forming a hardened network of considerable *** the morphology and performance of these types of foams changes slightly with the change in the amount of glutaraldehyde and hexamine hardeners,the best performing foam formulation previously determined was scanned by SEM and analysed chemically for the structures formed.

关键词： Hydrolysable tannin chestnut tannin non-isocyanate bio polyurethanes NIPU MALDI-ToF ^(13)C NMR SEM bio-based materials

Self-Blowing Non-Isocyanate Polyurethane Foams Based on Hydrolysable Tannins

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Journal of Renewable Materials 2022年第12期10卷 3217-3227页

作者： elham azadeh Xinyi Chen Antonio Pizzi Christine Gérardin Philip Gérardin Hisham Essawy Facultédes Sciences et Technologies LERMABEA 4370-USC INRAEUniversity of LorraineBlvd des AiguillettesNancy54506France LERMAB EA 4370-USC INRAEUniversity of Lorraine27 rue Philippe SeguinEpinal88000France Department of Polymers and Pigments National Research CenterCairo12622Egypt

ABSTRACT Non-isocyanate polyurethane(NIPU)foams using a hydrolysable tannin,also vulgarly called tannic acid,namely here commercial chestnut wood tannin extract was *** strength did not appear to depend on the foam apparent density while the formulation composition of the NIPU foams has been shown to be more *** NIPU foams appeared to be self-extinguishing once the high temperature flame is *** ignition time gave encouraging results but for improved fire resistance the foams may need some fire-retardant *** spectrometry showed the formation of non-isocyanate urethane *** analysis indicated a good thermal resistance of these foams,with thermal degradation following four *** in the interval 25℃–120℃ range,mainly evaporation of water occurs with a maximal loss of 10%*** the 150℃–450℃ temperature range foams mass loss is of almost 70%.In particular in the 125℃–275℃ range occurs the degradation of some small molecular weight *** the 500℃–790℃ temperature range the foams do not present any further large degradation.

关键词： Non-isocyanate biopolyurethanes(NIPU) biofoams chestnut tannin hydrolysable tannins self-extinguishing

Flexible Biofoams Based on Furanics and Fatty Acids Esterified Tannin

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Journal of Renewable Materials 2023年第10期11卷 3625-3645页

作者： elham azadeh Ummi Hani Abdullah Christine Gerardin Antonio Pizzi Philippe Gerardin Cesar Segovia LERMAB University of LorraineBlvd des AiguillettesNancy54000France Department of Wood and Fiber Industries Faculty of Forestry and EnvironmentUniversiti Putra MalaysiaSerdangSelangor43400Malaysia Institute of Tropical Forestry and Forest Products(INTROP) Universiti Putra MalaysiaSerdangSelangor43400Malaysia CETELOR University of LorraineEpinal88000France

Water repellant,flexible biofoams using tannin esterified with various fatty acid chains,namely lauric,palmitic and oleic acids,by reaction with lauryl chloride,palmitoyl chloride,and oleyl chloride were developed and their characteristics compared with the equivalently esterified rigid ***,while initially added to control the reaction temperature,was used as a plasticizer yielding flexible biofoams presenting the same water repellant character that the equivalent rigid *** was used as the cross-linking agent instead of formaldehyde,as it showed a better performance with the esterified *** compression results showed a significant decrease of the Modulus of Elasticity(MOE)of the flexible foams in relation to that of the rigid foams,confirming their flexible *** lauryl-and palmitoyl-esterified biofoams presented similar mechanical properties,while the oleyl-esterified biofoam presented different mechanical and morphological result not really showing the expected *** the esterified rigid and flexible tannin-based biofoams showed good water resistance and their sessile drop contact angle analysis as a function of time confirmed this *** Electron Microscope(SEM)analysis showed the flexible foams to present a higher proportion of closed cells than the rigid ***,the cells depth of the flexible foams was lower than that of the rigid *** regards their thermal resistance,the flexible foams showed a slight loss of mass compared to the rigid ones without *** types of foams presented much lower surface friability of non-esterified rigid foams.

关键词： Flexible tannin-furanic foams esterified tannins water repellence TGA SEM compression

Modification of Wood by Tannin-Furfuryl Alcohol Resins-Effect on Dimensional Stability,Mechanical Properties and Decay Durability

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Journal of Renewable Materials 2023年第2期11卷 505-521页

作者： Mahdi Mubarok Christine Gérardin-Charbonnier elham azadeh Firmin Obounou AkongStéphane Dumarçay Antonio Pizzi Philippe Gérardin Universitéde Lorraine INRAEUR 4370 USC 1445 LERMABFacultédes Sciences et TechnologiesNancyFrance 2 Forest Product Sciences and TechnologyFaculty of Forestry and EnvironmentIPB UniversityBogorIndonesia

Furfurylation is a well-known wood modification *** paper studied the effect of tannin addition on the wood *** kinds of dicarboxylic acids,adipic acid,succinic acid,and tartaric acid,as well as glyoxal as a comparing agent,were used to catalyse the polymerisation of furanic or tannin-furanic solutions during wood *** of furanic or tannin-furanic solution at a certain concentration into the wood followed with curing at 103℃for a specific duration was performed for the wood *** properties of the modified woods like dimensional stability,resistance of treatment to leaching,mechanical properties,decay durability against white-rot(Coriolus versicolor,Pycnoporus sanguineus)and brown-rot(Coniophora puteana)as well as their chemical and anatomical characteristics were *** revealed that the partial substitution of FA by the tannins improved the fixation of the chemicals impregnated in ***,dimensional stability,leaching resistance,Brinell hardness,modulus of elasticity/modulus of rupture,and decay durability properties of the furfurylated wood were also improved in the presence of *** electron microscopy revealed the deposition of the polymer in the wood lumen cells and in the wood cell walls.

关键词： Decay durability furfuryl alcohol leaching resistance mechanical properties tannin

Placental pathologies and fetal outcome in pregnant women with COVID-19: A retrospective study

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Asian pacific Journal of Reproduction 2022年第3期11卷 132-137,I0001-I0003页

作者： Soheila Sarmadi Ara Omranipour elham Mirzaian Roghayyeh Ahangari Zahra Yazdi azadeh Asgarian Monireh Mirzaie Department of Pathology Yas HospitalTehran University of Medical SciencesTehranIran Department of Obstetrics and Gynecology School of MedicineShahid Beheshti HospitalQom University of Medical SciencesQomIran Department of Pathology Shariati HospitalSchool of MedicineTehran University of Medical SciencesTehranIran Department of Obstetrics and Gynecology Clinical Research Development UnitSchool of MedicineNekouei-Hedayati-Forghani HospitalQom University of Medical SciencesQomIran Department of Nursing Clinical Research Development UnitNekouei-Hedayati-Forghani HospitalQom University of Medical SciencesQomIran

Objective:To describe histopathologic findings in the placentas in women with coronavirus disease 2019(COVID-19)during ***:In a cross-sectional study,38 pregnant women with COVID-19 and undergoing delivery between March 2020 and January 2022,were *** patients had positive polymerase chain reaction(PCR)test for SARS-CoV-2 infection and the placentas after delivery were sent for histopathologic evaluation based on the Amsterdam Placental Workshop Group Consensus Statement and assessed by two ***:Our results showed that maternal vascular malperfusion was the most common and was present in 17 cases(44.7%).These features included accelerated villous maturation(36.8%)distal villous hypoplasia(5.3%),placental infarction(5.3%)and intervillous fibrin deposition(10.5%).Other pathologic findings included focal calcification(10.5%),intravillous congestion and hemorrhage(10.5%),sub-chorionic hemorrhage(5.3%),acute villitis,chronic histiocytic intervillositis and delayed villous maturation each in one case(2.6%).Twelve out of 38 cases showed no significant pathologic *** outcomes included neonatal intensive care unit admission rate of 13.2%,dyspnea 31.6%,newborn’s anosmia 7.9%,intrauterine fetal demise 2.6%,asphyxia 2.6%and neonate COVID infection 5.3%.Conclusions:Microvasculopathy,as a sign of maternal vascular malperfusion,is a common finding in placentas from SARS-CoV-2 positive pregnant women in the present *** studies with larger sample sizes and comparative studies between COVID-19 positive and negative,as well as information from patient follow-up are suggested.

关键词： Pregnant women Placental Pregnancy Pathology Mother Maternal arteries sitefusion COVID-19