|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Performance of Unidirectional Biocomposite Developed with Piptadeniastrum Africanum Tannin Resin and Urena Lobata Fibers as Reinforcement显示文摘The Piptadeniastrum Africanum bark tannin extract was characterized using MALDI TOF,ATR-FT MIR.It was used in the development of a resin with Vachellia nilotica extract as a biohardener.This tannin is consisting of Catechin,Quercetin,Chalcone,Gallocatechin,Epigallocatechin gallate,Epicatechin gallate.The gel time of the resin at natural pH(pH=5.4)is 660 s and its MOE obtained by thermomechanical analysis is 3909 MPa.The tenacity of Urena lobata fibers were tested,woven into unidirectional mats(UD),and used as reinforcement in the development of biocomposite.The fibers tenacity at 20,30 and 50 mm lengths are respectively 65.41,41.04 and 33.86 cN·Tex^(−1).The UD biocomposite obtained had very interesting mechanical properties.Its density,tensile MOE,ultimate strength,bending MOE and MOR are respectively 926 kg·m^(−3),6 GPa,55 MPa,9.3 GPa and 68.3 MPa.This biocomposite can be used in a building exterior structure. | Achille Gnassiri Wedaïna Antonio Pizzi Wolfgang Nzie Raidandi Danwe Noel Konaï Siham Amirou Cesar Segovia Raphaël Kueny | 2021 | Journal of Renewable Materials2021，9，3： | 0 |
| 2 | Flexible Biofoams Based on Furanics and Fatty Acids Esterified Tannin显示文摘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 biofoams.Glycerol,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 foams.Acetaldehyde was used as the cross-linking agent instead of formaldehyde,as it showed a better performance with the esterified tannin.The 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 character.The 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 flexibility.Both 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 characteristic.Scanning Electron Microscope(SEM)analysis showed the flexible foams to present a higher proportion of closed cells than the rigid foams.Conversely,the cells depth of the flexible foams was lower than that of the rigid foam.As regards their thermal resistance,the flexible foams showed a slight loss of mass compared to the rigid ones without glycerol.Both types of foams presented much lower surface friability of non-esterified rigid foams. | Elham Azadeh Ummi Hani Abdullah Christine Gerardin Antonio Pizzi Philippe Gerardin Cesar Segovia | 2023 | Journal of Renewable Materials2023，11，10： | 0 |
| 3 | Lignocellulosic Micro and Nanofibrillated Cellulose Produced by Steam Explosion for Wood Adhesive Formulations显示文摘The reinforcing impact of Lignocellulosic micro and nanofibrillated cellulose(L-MNFCs)obtained from Eucalyp-tus Globulus bark in Urea-Formaldehyde UF adhesive was tested.L-MNFCs were prepared by an environmentally friendly,low-cost process using a combination process involving steam explosion followed by refining and ultra-fine grinding.Obtained L-MNFCs showed a web-like morphology with some aggregates and lignin nanodroplets.They present a mixture of residual fibers and fine elements with a width varying between 5 nm to 20μm,respec-tively.The effects of the addition of low amounts of L-MNFCs(1%wt.)on the properties of three different adhe-sives(Urea-Formaldehyde UF,Phenol-Formaldehyde PF,and Tannin-Hexamine TH)were studied by the evolution of the pH,the viscosity,and the mechanical properties.Results showed that the viscosity of PF and UF adhesives increased with the addition of L-MNFCs,unlike TH.Meanwhile,the addition led to better mechan-ical behavior for the three adhesives.Particleboards were then prepared using modified UF with L-MNFCs and tested.Results showed that an amount of 1%wt.of L-MNFCs was sufficient to increase the internal bonding by≈67%,the modulus of elasticity by≈43%,and the modulus of rupture by≈29%. | Saad Nader Felipe Guzman Raphael Becar Cesar Segovia Cecilia Fuentealba Miguel Peirera Evelyne Mauret Nicolas Brosse | 2022 | Journal of Renewable Materials2022，10，2： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员