Waste tire rubber as low-cost and environmentally-friendly modifier in thermoset polymers - A review

Nowadays, waste tire rubber (WTR) management is a growing and serious problem. Therefore, research works focused on the development of cost-effective and environmentally-friendly methods of WTR recycling are fully justified. Incorporation of WTR into polymer matrices and composite materials attracts much attention, because this approach allows sustainable development of industrially applicable waste tires recycling technologies. Generally, utilization of WTR as a filler for polymer composites noticeably reduces materials costs, while suitable modification/functionalization of WTR may significantly enhance the performance of plastics and rubbers. This work aims to summarize the literature reports related to the thermoset/WTR composites based on various matrices such as: polyurethanes, epoxy and other resins. It particularly focuses on compatibilization strategies in thermosets/WTR systems and their impact on the chemistry and physical interfacial interactions between thermoset matrix and WTR filler phase, what significantly affecting performance properties of prepared materials. Moreover, future trends and limitation related to thermoset/WTR composites development are discussed.

Rigid Polyurethane Foams Modified with Ground Tire Rubber - Mechanical, Morphological and Thermal Studies

Rigid polyurethane foams, prepared by a single step method, were modified with the two types of ground tire rubber particles, i.e. untreated and thermo-mechanically reclaimed using a co-rotating twin screw extruder. The foaming process as well as the structure and the physical, mechanical and thermal properties of the resulting foams were investigated. The presence of ground tire rubber decreased the rate of polymerization. The incorporation of ground tire rubber decreased the total crosslink density of the produced material, as confirmed by a decrease in glass transition temperature measured by dynamic mechanical analysis and differential scanning calorimetry. The temperatures associated with a 10% and 50% mass loss of foam, determined by thermogravimetric analysis, increased due to the addition of ground tire rubber particles.