Assessment of the devulcanization process of EPDM waste from roofing systems by combined thermomechanical/microwave procedures

Colom, X.; Cañavate, Javier; Formela, Krzysztof; Shadman, Alireza; Saeb, Mohammad Reza

doi:10.1016/j.polymdegradstab.2020.109450

Cited by 27 publications

(28 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, it should be pointed that during peroxide curing, it is also possible that the peroxide-induced degradation of GTR might occur. Sabzekar et al [ 43 ] and Colom et al [ 44 ] studied the effect of BPO on the thermo-mechanical devulcanization of waste rubber, but due to a similarity in the peroxide decomposition mechanisms for other peroxides, similar effects can be expected. In the case of BIB and DCP, some differences are related to their affinity of GTR and NBR.…”

Section: Resultsmentioning

confidence: 99%

GTR/NBR/Silica Composites Performance Properties as a Function of Curing System: Sulfur versus Peroxides

et al. 2021

View full text Add to dashboard Cite

In this work, conventional sulfur and two types of organic peroxides (dicumyl peroxide (DCP) and di-(2-tert-butyl-peroxyisopropyl)-benzene (BIB)) curing systems were used to investigate the possibility for tailoring of the performance properties of GTR/NBR blends reinforced with a variable content of highly dispersive silica (0–30 phr). The curing characteristics, static mechanical and acoustical properties, swelling behavior, thermal stability, and microstructure of the prepared composites were investigated. The results show that regardless of the curing system used, increasing the content of highly dispersive silica resulted in the improvement of the mechanical properties of the studied materials. It was observed that sulfur-based systems are the best choice in terms of cross-linking efficiency determined based on torque increment and cross-link density parameters. However, further analysis of the physico-mechanical properties indicated that the cross-linking efficiency does not match the performance of specimens, and the materials obtained using organic peroxides show higher tensile properties. This is due to the improved physical interactions between the GTR/NBR matrix and highly dispersive silica when using peroxide systems. It was confirmed using the analysis of the Wolff activity coefficient, indicating the enhanced synergy.

show abstract

Section: Resultsmentioning

confidence: 99%

GTR/NBR/Silica Composites Performance Properties as a Function of Curing System: Sulfur versus Peroxides

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Intensive studies have been carried out in the last decades to break down the crosslinked rubber network by devulcanization. This involves treating rubber waste thermo‐mechanical, 1,2 chemically, 3–5 biologically, 6–8 with ultrasound 9,10 and microwaves, 11,12 or by a combination 13 of such methods to achieve selective cleavage of C‐S and S‐S bonds without additional damage of C‐C bonds in the polymer backbone. Devulcanization as a reversible process of vulcanization is the standard processing method for the material recovery of rubber waste.…”

Section: Introductionmentioning

confidence: 99%

Devulcanization of ethylene‐propylene‐diene monomer rubber waste. Effect of diphenyl disulfide derivate as devulcanizing agent on vulcanization, and devulcanization process

Gschwind

Jordan

Vennemann³

2022

J of Applied Polymer Sci

View full text Add to dashboard Cite

A systematic study was performed to understand the effects of the devulcanizing agent dibenzamido diphenyl disulfide (DBD) on the vulcanization and devulcanization process of a sulfur‐cured ethylene‐propylene‐diene monomer (EPDM) rubber. The influence of DBD on vulcanization was investigated by mixing DBD with virgin rubber and curative system. The devulcanization of rubber waste was achieved with varying amounts of DBD ranging from 0.4 to 13.8 wt% and temperatures from 150 to 200°C. The quality of vulcanizates and devulcanizates was evaluated by rheometer tests, temperature scanning stress relaxation measurements, and analysis of mechanical properties. During vulcanization, DBD acts as an accelerator in the presence of sulfur. When accelerators are added, the scorch time increases, and the cure rate decreases. Thus, DBD acts as a retarder. In the presence of activators, DBD leads to a significant reduction of crosslink density. This results in composites with high elongation at break and poor compression set values. The efficiency of the devulcanization of rubber waste depends strongly on DBD concentration and temperature. The monosulfidic crosslinks are cleaved by low concentrations of DBD, while polysulfidic crosslinks require higher concentrations. These results show that DBD is effective as a devulcanizing agent and degrades the network below 200°C.

show abstract

“…EPDM rubber has several uses in the automotive industry (profiles, hoses, seals), electrical and construction industries, aerospace or nuclear technology. EPDM is also utilized as a dielectric material for cable and wire insulation, especially cables in nuclear power plants which are subjected to thermal and radiation attacks during their utilization, and as an insulator matrix in rocket combustion chambers due to its excellent mechanical, chemical and electrical characteristics [ 7 , 8 , 9 , 10 ].…”

Section: Introductionmentioning

confidence: 99%

Dielectric, Thermal and Water Absorption Properties of Some EPDM/Flax Fiber Composites

Airinei¹,

Asăndulesa²,

Stelescu

et al. 2021

Polymers

View full text Add to dashboard Cite

This paper deals with the dielectric and sorption properties of some flax fiber-reinforced ethylene-propylene-diene monomer (EPDM) composites containing different fiber loadings as well as their behavior after exposure to different doses of electron beam irradiation. Three relaxation processes were evinced, a weak relaxation β at sub-Tg temperatures and two α-type relaxations above the Tg. The EPDM/flax composites exhibited higher values of dielectric constant, dielectric loss and conductivity as compared to a pristine EPDM sample. Using thermogravimetric analysis (TG) coupled with Fourier transform infrared spectroscopy (FTIR) and mass spectrometry (MS) (TG/FTIR/MS system), the degradation products can be identified. The water uptake increased as the flax fiber level increased in composites. The water uptake tests of irradiated composites showed that the highest water content was obtained for a flax fiber level of 20 phr.

show abstract

Assessment of the devulcanization process of EPDM waste from roofing systems by combined thermomechanical/microwave procedures

Cited by 27 publications

References 35 publications

GTR/NBR/Silica Composites Performance Properties as a Function of Curing System: Sulfur versus Peroxides

GTR/NBR/Silica Composites Performance Properties as a Function of Curing System: Sulfur versus Peroxides

Devulcanization of ethylene‐propylene‐diene monomer rubber waste. Effect of diphenyl disulfide derivate as devulcanizing agent on vulcanization, and devulcanization process

Dielectric, Thermal and Water Absorption Properties of Some EPDM/Flax Fiber Composites

Contact Info

Product

Resources

About