Preparation of PO43−-Intercalated Calcium–Aluminum Hydrotalcites via Coprecipitation Method and Its Flame-Retardant Effect on Bamboo Scrimber

Abstract

To improve the flame retardancy of bamboo scrimber, flame-retardant CaAl-PO4-LDHs were synthesized via the coprecipitation method using PO43− as the anion of an intercalated calcium–aluminum hydrotalcite in this work. The fine CaAl-PO4-LDHs were characterized via X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), cold field scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) and thermogravimetry (TG). Different concentrations (1% and 2%) of CaAl-PO4-LDHs were used as flame retardants for the bamboo scrimber, and the flame retardancy of the bamboo scrimber was characterized via cone calorimetry. The results showed that CaAl-PO4-LDHs with excellent structures were successfully synthesized via the coprecipitation method in 6 h and at 120 °C. Compared with the bamboo scrimber without the flame retardant treatment, the peak heat release rate (HRR) of the bamboo scrimber treated with 1% and 2% concentrations of flame-retardant CaAl-PO4-LDHs decreased by 16.62% and 34.46%, the time taken to reach the exothermic peak was delayed by 103 s and 204 s and the Time to Ignition (TTI) was increased by 30% and 40%, respectively. Furthermore, the residual carbon of the bamboo scrimber did not change significantly, increasing by 0.8% and 2.08%, respectively. CO production decreased by 18.87% and 26.42%, respectively, and CO2 production decreased by 11.11% and 14.46%, respectively. The combined results show that the CaAl-PO4-LDHs synthesized in this work significantly improved the flame retardancy of bamboo scrimber. This work exhibited the great potential of the CaAl-PO4-LDHs, which were successfully synthesized via the coprecipitation method and applied as a flame retardant to improve the fire safety of bamboo scrimber.

Preeminent Flame-Retardant and Smoke Suppression Properties of PCaAl-LDHs Nanostructures on Bamboo Scrimber

“…By employing the coprecipitation method under specific process conditions of the crystallization temperature of 120 • C and a crystallization time of 6 h, the flame retardant PCaAl-LDHs with an excellent flame retardant performance was successfully synthesized. The specific synthesis process of the PCaAl-LDHs could be referred to in our previous work [41]. The rough surface structure of bamboo bundles endowed them with exceptional adsorption properties.…”

High-Throughput, In Situ Preparation of Mg–Al Hydrotalcites and Tandem Self-Condensation of Cyclopentanone Integrated via the Ball-Milling Process

“…18 It has the disadvantages of long preparation time (20 h) and complicated reaction steps. 19 Therefore, it is important to create a simple and efficient preparation method for hydrotalcite with high catalytic properties.…”

“…At present, the main methods for preparing Mg–Al hydrotalcite include the coprecipitation method, urea method, and sol–gel method . It has the disadvantages of long preparation time (20 h) and complicated reaction steps . Therefore, it is important to create a simple and efficient preparation method for hydrotalcite with high catalytic properties.…”