Abstract:Composites have been prepared from devulcanized waste ethylene propylene diene monomer (W‐EPDM) rubber by blending with low‐density polyethylene (LDPE) in a twin‐screw extruder. W‐EPDM was treated separately by optimized microwave and ultrasonic radiation. Effect of compatibilizer such as ethylene octane elastomeric copolymer (POE) on the enhancement of mechanical properties of composites was also studied in addition to the radiation treatment. The enhancement of tensile strength (TS) and elongation at break o… Show more
“…The microwave devulcanization, used in this study, has proved to be an efficient technique. This method enables to apply large amounts of energy rapidly and uniformly to the rubber, without using chemical reagents during the process [17,18], which makes it an eco-friendly process [19]. The energy used to heat the rubber promotes the breaking of sulfur cross-links [13].…”
Abstract.Microwave devulcanization is known to be a promising and an efficient rubber recycling method which makes possible for the rubber to regain its fluidity, and makes it capable of being remolded and revulcanized. The focus of this work is to understand the physical and chemical changes that occur in the ground tire rubber after different microwave exposure periods. For this purpose chemical, thermal, rheological and morphological analyses were performed on the tire rubber, which contains natural rubber (NR) and styrene-butadiene rubber (SBR) as polymeric material. The results showed that the microwave treatment promoted the breaking of sulfur cross-links and consequently increased the rubber fluidity. However, long periods of exposure led to degradation and modification of some properties. At nanoscale, the deformation of the devulcanized NR domain under stress was observed, and the morphology obtained appears to be a droplet dispersion morphology. The most exposed samples presented only one glass transition temperature, and from this it was concluded that the treatment may have played an important role in the compatibilization of the elastomeric blend. Based on the results, it is required to control the microwave exposure time and polymeric degradation in order to achieve a regenerated rubber with satisfactory properties.
“…The microwave devulcanization, used in this study, has proved to be an efficient technique. This method enables to apply large amounts of energy rapidly and uniformly to the rubber, without using chemical reagents during the process [17,18], which makes it an eco-friendly process [19]. The energy used to heat the rubber promotes the breaking of sulfur cross-links [13].…”
Abstract.Microwave devulcanization is known to be a promising and an efficient rubber recycling method which makes possible for the rubber to regain its fluidity, and makes it capable of being remolded and revulcanized. The focus of this work is to understand the physical and chemical changes that occur in the ground tire rubber after different microwave exposure periods. For this purpose chemical, thermal, rheological and morphological analyses were performed on the tire rubber, which contains natural rubber (NR) and styrene-butadiene rubber (SBR) as polymeric material. The results showed that the microwave treatment promoted the breaking of sulfur cross-links and consequently increased the rubber fluidity. However, long periods of exposure led to degradation and modification of some properties. At nanoscale, the deformation of the devulcanized NR domain under stress was observed, and the morphology obtained appears to be a droplet dispersion morphology. The most exposed samples presented only one glass transition temperature, and from this it was concluded that the treatment may have played an important role in the compatibilization of the elastomeric blend. Based on the results, it is required to control the microwave exposure time and polymeric degradation in order to achieve a regenerated rubber with satisfactory properties.
“…The process has physical nature, i.e. it does not involve chemicals during the process and due to this reason is named ecofriendly 39 . Devulcanization of elastomers by microwaves shows promising results for recycling rubber 3,10,[12][13][14][15][16][17][18]40 .…”
Section: Introductionmentioning
confidence: 99%
“…This technique is widely mentioned by the literature to detect the status of devulcanization of elastomers 4,5,[14][15][16]24,31,32,39,41,[43][44][45][46][47][48][49][50][51][52] . In general, the content of soluble material (sol) increases with the increasing of devulcanization degree, due to the breaks of the cross-linkings and, consequently, the release of these molecules from the three-dimensional network of vulcanized rubber.…”
“…The authors highlighted the beneficial effects of DPDS on the efficiency of microwave devulcanization process. In another study, Hong et al [14] also compared devulcanization performance of microwave and ultrasonic procedures and concluded that microwave technique is better than ultrasonic method. To improve devulcanization efficiency and reduce treatment energy, promising new approach consists of impregnation of the waste rubber with solvent and then heat treating the impregnated material with microwave radiation.…”
Abstract. In this study, styrene butadiene rubber (SBR) was devulcanized using microwave irradiation. In particular, effect of ionic liquid (IL), pyrrolidinium hydrogen sulfate [Pyrr] [HSO 4 ], on the devulcanization performance was studied. It was observed that the evolution of the temperature reached by rubber powder exposed to microwave irradiation for different energy values was favored by the presence of ionic liquid [Pyrr] [HSO 4 ] significantly over the whole range of the microwave energy values. Beyond the threshold point of 220 Wh/kg, the soluble fraction after devulcanization sharply increased with increasing devulcanization microwave energy. For the powder mixed with [Pyrr][HSO 4 ], the increase was more significant. Furthermore, the crosslink density was observed to decrease slowly with the microwave energy up to 220 Wh/kg, beyond which the crosslink density decreased significantly for the rubber impregnated with IL. For the rubber with IL, significant and continuous increase in T g with microwave energy values was observed in comparison with the SBR where no change in transition temperature was observed. Mechanical shearing of rubber gums in the two-roll mill favored the devulcanization process, which indicated that the combination of mechanical loading with microwave energy and IL is an efficient procedure allowing an optimal devulcanization of rubbers.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.