Effects of blowing agents and curing temperatures on physical and mechanical properties of natural rubber foam for laminated floor tiles

Abstract

Falling on the floor has been one of the most common causes of breaking a bone. Falls in senior homes and care facilities can lead to immobility symptoms and treatments. Rubber flooring is a great alternative for fall protection. Thus, this study aimed to investigate the effects of organic blowing agents (dinitroso pentamethylene tetramine and azodicarbonamide) on the physical and mechanical properties of natural rubber foam used for laminated floor tiles. The curing temperatures were also examined in the range of 140–160 oC. From the experimental results, the blowing agent was an important component added to the rubber foam layer at various contents and temperatures. The compression set increased when curing temperatures and adding blowing agent increased. With an increase in the curing temperature, the elongation at break decreased. The findings indicated that the mechanical properties of natural rubber foam were significantly affected by the kind of blowing agent and the curing temperature. Finally, an optimal energy absorption was found in the dinitroso pentamethylene tetramine condition with 3 phr and the curing temperature of 160°C, which offers the maximum energy absorption value of 110 J.

Facial fabrication of self‐healing natural rubber foam based on zinc thiolate ionic networks

“…These findings align with the observations of Petdee et al, 27 who noted that increasing the blowing agent concentration leads to a reduction in the density of NR foam. This reduction in density offers various benefits in the manufacturing of foam‐based products.…”

“…The presence of higher amounts of CO 2 gas generated during the foaming process leads to a thinner cell wall thickness and consequently contributes to the reduction in weight of the SHNR foam. This effect is consistent with the findings of Petdee et al, 27 who observed that the volume fraction of the rubber compound doubled from 35% to 70% as the pore or cell sizes increased. As a result, the density of the foam decreased from 0.41 to 0.73 g/cm 3 .…”

“…However, it is worth noting that different studies have reported varied effects of adding blowing agents on elongation at break. Petdee et al 27 and Tang et al 28 found that adding a blowing agent to foams initially increased the elongation at break, but it eventually decreased when the blowing agent loading exceeded the optimum level. This behavior can be attributed to the initiation of cell wall rupture and slow strain development caused by the small‐sized cells in the rubber foam during stretching and crack formation.…”