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

Abstract

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.

The Impact of Ground Tire Rubber Oxidation with H2O2 and KMnO4 on the Structure and Performance of Flexible Polyurethane/Ground Tire Rubber Composite Foams

“…Such an effect could be associated with the noticeable increase of the polyol mixture's viscosity related to the incorporation of GTR. A similar phenomenon was noted in our previous works [39,40]. As shown in the SEM images of modified GTR (Figure 3), treatment with hydrogen peroxide caused surface development, which resulted in the enhanced interactions with the polyol mixture.…”

“…The introduction of GTR into polyurethane foam reduced the maximum foam temperature during polymerization. It was associated with the interactions between GTR and isocyanates and confirms the results of previous works [39,40]. Moreover, the maximum temperature is reached almost 30 s later than for unfilled polyurethane foam, which confirms the processing times' elongation due to the polyol mixture's increased viscosity.…”

“…Such an effect may be related to the lower stability of introduced rubber particles than the polyurethane matrix, due to its oxidation (see Table 3). Similar effects were observed in our previous works, when partially devulcanized rubber was introduced into PU foams [39,40]. The effect was more pronounced for GTR modified with potassium permanganate, which is associated with the enhanced catalytic activity and weaker polyurethane matrix.…”

“…The introduction of GTR into the polyol mixture resulted mainly in the elongation of rise time. Such an effect was related to increased viscosity of the polyol mixture due to the incorporation of solid rubber particles, which was also noted in our previous works [39][40][41]. Nevertheless, in these works, we investigated the rigid polyurethane foams, so different material behavior was noted.…”

Preparation and properties of melamine-formaldehyde rigid closed-cell foam toughened by ethylene glycol/carbon fiber

“…More spherical closed-cell structure formed and the cellular strength can be improved by filler reinforcement. [26][27][28] In the last years, the use of reinforcements from natural resources, such as glass fiber, 29,30 nano-clay, 31 and nano-particles, 32 which possessed low density and cost, in polymeric foams had attracted the attention of many researchers. Liu et al fabricated the intrinsic flameretardant urea-formaldehyde/aramid fiber (UF/AF) composite foam, the incorporation of AF into UF foams could reduce the cell size and porosity.…”