High-performance thermoplastic elastomers (TPEs), based on recycled high-density polyethylene (HD-PE R ), olefinic type ethylene-propylene-diene monomer rubber (EPDM), and ground tire rubber (GTR) treated with bitumen, were prepared by using dynamic vulcanization technology, and their structure-property relationships were investigated. It was established that special pretreatment of GTR by bitumen confers outstanding mechanical properties on the resulting TPEs. TPEs, containing GTR pretreated by bitumen, exhibit thermal behavior similar to that of the HDPE R /EPDM basic blend in the temperature region up to about 340°C. Rheological measurements showed that bitumen acts as an effective plasticizer for the GTR-containing TPEs. SEM, DSC, and DMTA results revealed improved adhesion between the particles of GTR treated by bitumen and the surrounding thermoplastic matrix, compared to that of the untreated GTR particles. It was concluded that bitumen acts as an effective devulcanizing agent in the GTR treatment stage. In the following steps of TPE production, bitumen acts simultaneously as a curing agent for the rubber components (EPDM/GTR) and as a compatibilizer for the blend components. GTR-containing TPEs, prepared by extrusion technology, were reprocessed (by passing through the extruder six times) without any observable changes in their tensile properties, thermal stability, and melt viscosity.

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Thermosetting polymers are widely used as industrial materials due to good heat resistance, dimensional stability and chemical resistance. There is a longstanding and widespread interest in designing novel polymer networks, and utilization of ionic liquids (ILs) opens up new frontiers to meet this challenge by creating new materials. For thermosetting polymers, ILs offer many advantages, either as catalytic agents, plasticizers, conducting additives, or porogens. Furthermore, ILs show rich structural diversity and can be incorporated into a polymer matrix to achieve better final properties. This review emphasizes the urgent need for understanding the role, efficiency and perspectives of an innovative class of components, namely ILs with the potential to impact across many areas of thermosetting polymers. To avoid ambiguity and make the review selfreading, basic ideas about the application of ILs in thermosetting polymers are first outlined.

Thermochemically partially devulcanized ground tire rubber (GTRD) was revulcanized in compositions with different virgin rubbers. Two different devulcanizing groups (mixture of softeners) with and without processing oil have been used for GTR treatment. As virgin rubbers methylstyrene/butadiene (SBR), isoprene (IR) and butadiene (BR) rubbers or their combinations were selected. They were cured by using sulfur, tetramethyl thiuram disulfide (TMTD) or peroxide based vulcanizing systems. The Rubber/GTRD (re)vulcanizates with the GTRD content from 20 to 80 wt. % have been prepared and studied. Vulcanization by sulfur system was found as preferable for IR/GTRD formulations. The best properties for BR/GTRD and SBR/GTRD vulcanizates were reached with the vulcanization system based on TMTD. The co-curing in the interphase between the GTRD particles and the surrounding rubber matrix improves the mechanical properties of (re)vulcanizates obtained. The reclaimed GTRD studied has been used successfully in standard formulations for tires instead of the part of virgin rubbers.