Polyurethane‐layered double hydroxide nanocomposite foam: in situ synthesis by reaction injection molding and characterization.

In the present work, a series of polyurethane ayered double hydroxide (PU‐LDH) nanocomposite molded foams were developed using Mg/Al LDH as the chemical blowing agent. Morphological, physicochemical, thermal and mechanical characterizations were performed to elucidate the mechanistic insight of the chemical blowing effect of the LDH and subsequently its enhanced blowing (foam formation) property. The characterization of standard urethane peaks by Fourier transform infrared spectroscopy attenuated total reflectance (FTIR‐ATR) studies confirmed PU foam formation. The DSC thermogram of all the PU‐LDH nanocomposite foams shows a low temperature glass transition for the soft segment (Tg) and a high temperature peak related to the hard segment. The TGA and DSC studies also reveal an improved phase separation behavior of the nanocomposite foam with increase in LDH content. The volume of the foam generated is increased with increase in LDH. The developed PU‐LDH nanocomposite foams are flexible and light weight. The results demonstrate that LDH can be an alternative cost effective and environmentally friendly blowing agent, whilst supporting other thermal, mechanical and chemical properties through synergistic optimization for the intended/specific application. © 2022 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]