Ground Tire Rubber Modified by Ethylene-Vinyl Acetate Copolymer: Processing, Physico-Mechanical Properties, Volatile Organic Compounds Emission and Recycling Possibility

Abstract

Ground tire rubber (GTR) was reclaimed and modified with 10 phr of ethylene-vinyl acetate copolymer via low-temperature extrusion process. Processing, physico-mechanical properties, volatile organic compounds emission, and recycling possibility were investigated. In order to better understand the impact of used modifiers, their efficiency was compared with trans-polyoctenamer, which is an additive that is commercially dedicated to waste rubber recycling. The results showed that a relatively small amount of ethylene-vinyl acetate copolymer improves the mechanical properties of modified reclaimed GTR and also allows further recycling by multiple processing without the deterioration of performance after three cycles.

Processing, Performance Properties, and Storage Stability of Ground Tire Rubber Modified by Dicumyl Peroxide and Ethylene-Vinyl Acetate Copolymers

“…The tensile properties of the GTR modified EVA copolymers in most compositions an exception was the sample with 2.5 phr of EVA-39%) were higher compared to the reference sample (GTR DCP ). Moreover, the prepared modified GTR showed tensile properties comparable or even higher than those of commercially available reclaimed rubbers (~4-5 MPa) [30], which fully justifies the application of GTR modification.…”

“…Our previous work [30] showed that using of a relatively small amount (10 phr) of ethylene-vinyl acetate copolymer during low-temperature devulcanization resulted in the improvement of the tensile properties of the modified reclaimed GTR, which were also higher compared to GTR modified by trans-polyoctenamer (an additive commonly used in waste rubber recycling). Furthermore, the results showed that using of thermoplastics in GTR limits the emission of volatile organic compounds.…”

Ground Tire Rubber Filled Flexible Polyurethane Foam—Effect of Waste Rubber Treatment on Composite Performance

“…Such a low value points to the efficient polymerization of the system and a low portion of unbound extractives [ 76 ]. Higher sol fraction contents for composite foams are attributed to the noticeably higher value of this parameter for GTR itself (even over 10% [ 34 , 77 ]), as well as to the GTR interactions with the polyurethane matrix. The functional groups present on the surface of rubber particles (see GTR hydroxyl values in Table 2 ) may interact with isocyanates present in the polyurethane system, resulting in partially loose polyols macromolecules [ 78 ].…”

“…Moreover, the whole process (extrusion with specific screws configuration) generates shear forces adding additional energy to the system. In the work of Zedler et al [34], research was conducted on extrusion of modified rubber. The temperature settings of the Table 2 presents the properties of modified GTR samples, including the hydroxyl values (L OH ) determined according to the method based on the modified test method for isocyanate groups, as described in our previous works [28,29].…”

“…Moreover, the whole process (extrusion with specific screws configuration) generates shear forces adding additional energy to the system. In the work of Zedler et al [34], research was conducted on extrusion of modified rubber. The temperature settings of the extruder were as follows: 40/40/60/60/60/60/60/60/60/60/60 • C. Temperature measurements were conducted on the extruder nozzle using a thermal imaging camera.…”