The effect of adding chitin on the physical-mechanical properties of polyurethane foam

This study uses chitin as a filler for a polyurethane composite foam. The obtained polymer composite materials (PCM) are examined the technological parameters of the foaming (start time, rise time, and apparent density), the physical-mechanical properties (the compressive stress, compression set, resilience), and the cross-link density. The results present that the chitin-containing PCM with a filler ratio of 10% has no significant difference in the technological parameters of the foaming and the physical-mechanical properties. However, the physical-mechanical properties of elastic polyurethane foam (PUF)-chitin materials tend to change less than the semi-rigid PCMs. Furthermore, the cross-link density of obtained PCMs is increased compared with the blank PUFs due to an increase in the number of bonds between components in the polymer chain. Scanning electron microscopy analysis showed that the PCM with the filling has a larger pore size and a number of closed cells, and the pore's surface is rougher than the blank PUF. Waste-containing PCMs are developed to reduce the amount of solid waste in the environment. As a result, these PCMs became denser and stronger while reducing their elasticity and becoming heavier. Thus, the process of synthesis of chitin-containing PCM, using and recycling waste PCM, is circular.