Flame-Retardant and Smoke Suppression Properties of Nano MgAl-LDH Coating on Bamboo Prepared by an In Situ Reaction

Abstract

In recent years, bamboo has been widely used for building materials and household goods. However, bamboo is flammable, so a flame-retardant treatment for bamboo is urgently needed. In this work, nano MgAl-layered double hydroxide (MgAl-LDH) coated on bamboo, which was called MgAl-LB, was synthesized by an in situ one-step method. To determine the optimal in situ time, the effects of different reaction times on LDH growth on the bamboo surface and the flame retardancy of the MgAl-LBs were investigated. The SEM observations show that LDH growth on the surface of bamboo was basically saturated when the in situ reaction time was 24 h. Abrasion experiments show that MgAl-LDH coating has good abrasion resistance. The fire performance of the MgAl-LBs was evaluated by cone calorimeter tests, which indicated that the THR and TSP of the MgAl-LBs were significantly lower than those of untreated bamboo. Taking into account the energy consumption problem, determining the reaction time of 24 h is the optimal reaction time. Compared with untreated bamboo, the THR and TSP of MgAl-LB prepared at 24 h decreased by 33.3% and 88.9%, respectively.

Improving the Flame Retardancy of Bamboo Slices by Coating With Melamine–Phytate via Layer-by-Layer Assembly

“…The thermal degradation of the untreated bamboo can be divided into two stages (Figure 4A). The thermal degradation of main components of the untreated bamboo in different temperature ranges is as follows: 200-260°C for hemicellulose, 240-350°C for cellulose, and 280-500°C for lignin (Yao et al, 2019). The treated bamboo exhibited the same two stages of thermal deterioration as the untreated bamboo.…”

“…Many efforts have been devoted to improving the flame retardancy of bamboo. Traditional methods to improve the flame retardancy of bamboo materials included impregnation (Guo et al, 2019), copolymerization (Bidsorkhi et al, 2017), and surface coating (Yao et al, 2019). Although the impregnation method has the advantages of low cost and applicability, it needs to use high-voltage equipment.…”

Application of Nanotechnology in Wood-Based Products Industry: A Review

“…The findings showed that the oxygen index increased from 25.6 to 30.2% after being covered with a ZnO–TiO 2 coating, which revealed a significant enhancement of its flame retardant property. Layered double hydroxides [ 180 ] can absorb a large amount of heat, dilute the concentration of flammable gas, and absorb harmful acid gases during the decomposition process; therefore, it is an excellent flame retardant. Yao et al [ 180 ] applied nanomagnesium aluminium layered double hydroxide (Mg–Al LDH) to bamboo in an in situ one-step process and found that the total heat release and total smoke production were reduced by 33.3% and 88.9%, respectively, compared to those of samples without Mg–Al LDH.…”

“…Layered double hydroxides [ 180 ] can absorb a large amount of heat, dilute the concentration of flammable gas, and absorb harmful acid gases during the decomposition process; therefore, it is an excellent flame retardant. Yao et al [ 180 ] applied nanomagnesium aluminium layered double hydroxide (Mg–Al LDH) to bamboo in an in situ one-step process and found that the total heat release and total smoke production were reduced by 33.3% and 88.9%, respectively, compared to those of samples without Mg–Al LDH. Wang et al [ 181 ] introduced zinc-aluminum layered double hydroxide (Zn–Al LDH) nanostructures to wood and found that the peak heat release rate (PHRR) and total smoke production were reduced by 55% and 47%, respectively, compared to those of the pristine wood [ 181 ].…”

Electrospun Polystyrene/LDH Fibrous Membranes for the Removal of Cd2+ Ions

“…Among the known inorganic fillers, the addition of layered double hydroxide (LDH) to a polymer widens the scope of the applications of the produced composites. LDHs have found a wide range of applications, such as adsorption [4], separation [5], energy storage [6], corrosion protection [7], drug delivery [8], catalysis [9], and flame retardation [10].…”