Search results for "Epoxy"

Recycling of inside upholstery of end-of-life cars

2005

A model study for the recycling of the interior upholstery plastic parts of end-of-life cars has been carried out by reprocessing the homogenized scraps of an upholstery farm in the presence of different compatibilizer precursors, such as an ethylene-glycidylmethacrylate copolymer (EGMA), a maleic anhydride functionalized thermoplastic elastomer (SEBS-MA), etc. The investigated scraps contained recycled polyethylene (from agricultural uses) and poly(ethylene terephthalate), as the main components, plus minor proportions of polypropylene, polyamide-6, and other additives, including an ethylene copolymer (EC), probably an ethylene-acrylic acid copolymer, which is used to compatibilize the car…

Development of bio-based epoxy systems for dry-impregnated vegetables fiber composites implementation

2022

Prepregs find industrial applications thanks to their high thermomechanical properties and easy implementation. However, they have two major drawback. First, they needto be carried and stored at low temperature. The second drawback is linked to the use of solvent in the future matrix, generating VOCs during thermocompression process. Those two points leads to environmental and economical overcharges resolved by a new dry impregnation process developed by Fibroline company. Those PhD works are reporting the synthesis and formulation of a biobased powder system with a low environmental impact, non-toxic for humans and compatible with dry impregnation for fully bio-based composites implementat…

Prédiction de la contrainte de rupture de composites unidirectionnels et suivi de l'accumulation de ruptures de fibres

2005

Epoxy resin based matrices for advanced composites cured by ionizing radiation. Study of the influence of process parameters on final properties

2006

Novel epoxy formulations for high energy radiation curable composites

2005

Abstract It has been widely recognised that high energy radiation can be effectively applied to the cure of epoxy resins in applications as composite matrices or structural adhesives with improvements in product quality and/or reduction in production costs. In the presence of suitable initiators, polymerisation of epoxies occurs via cationic mechanism, thus restricting the choice of the resin system components to species which do not contain electron donor groups. The present investigation is aimed to identify suitable co-monomers to be formulated with an epoxy resin, resulting in different cure reaction kinetics and application properties of the cured resin. In particular, four different a…

Structural investigation of e-beam cured epoxy resins through solid state NMR

2012

Abstract In this paper the network structure of e-beam cured DGEBF based epoxy resins is investigated. Two epoxy systems, having different reactivity and cured in different process conditions, were analyzed through solid state NMR spectroscopy. The analysis shows that the more reactive system has higher cross-linking density and higher uniformity of network distribution. Similar information were obtained, in a previous work, on the same systems through dynamic mechanical thermal analysis. It is worth noting that unlike DMTA tests, which interfere with the molecular structure of the analyzed material, due to the heating during the analysis itself, more reliable information, without any artef…

Radiation curing of carbon fibre composites

2014

Epoxy/carbon fibre reinforced composites were produced by means of e-beam irradiation through a pulsed 10 MeV electron beam accelerator. The matrix consisted of a difunctional epoxy monomer (DGEBA) and an initiator of cationic polymerisation, while the reinforcement was a unidirectional high modulus carbon fibre fabric. Dynamic mechanical thermal analysis was carried out in order to determine the cross-linking degree. The analysis pointed out a nonuniformity in the cross-linking degree of the e-beam cured panels, with the formation of clusters at low Tg (glass transition temperature) and clusters at high Tg. An out-of-mould post irradiation thermal treatment on e-beam cured samples provides…

The influence of the processing temperature on gamma curing of epoxy resins for the production of advanced composites

2007

Abstract Gamma radiation curing of an epoxy monomer, in the presence of an iodonium salt, as initiator, is studied. Systems have been polymerized at the same irradiation dose and dose rate and at different processing temperatures. The experimental results show that all the irradiated materials exhibit a latent reactivity, undergoing toward an increase of crosslinking density if they are thermally cured after irradiation. The results indicate that the processing temperature affects both the crosslinking density after irradiation and the sensibility to the post-irradiation thermal treatment.

Cytotoxicity, antibacterial and physicochemical properties of a new epoxy resin-based endodontic sealer containing calcium hydroxide

2019

Background This study evaluated the cytotoxicity, antibacterial and physicochemical properties of a new epoxy resin-based endodontic sealer containing calcium-hydroxide Sealer Plus. AH Plus was used as a reference for comparison. Material and Methods Cytotoxicity evaluation was performed according to ISO-10993-5 specifications using MTT assay to check the 3T3 cells viability at 1- to 4-week periods. Antibacterial activity was evaluated using a direct contact test against Enterococcus faecalis. Radiopacity, solubility and flow evaluations were performed according to ISO-6876/2012 specifications. Setting time was assessed following the ANSI/ADA-standard-n.57. The pH level was measured at 3,24…

New reactive isoeugenol based phosphate flame retardant : toward green epoxy resins

2019

A biobased reactive phosphate flame retardant derived from isoeugenol was synthesized and fully characterized (1H, 13C, 31P NMR, FTIR, MS) with the aim of improving flame retardancy behavior of bio...