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

Xiaoling Yao,Rui Peng,Chungui Du,Yating Hua,Hongzhi Liu,Qiuli Huang,Jingjing Zhang

doi:10.1155/2019/9067510

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.

Highlights

In recent years, the demand for wood resources has gradually increased, but natural forestry is protected in China [1]
Structural information about the MgAl-Layered double hydroxides (LDHs) on the MgAl-LDH coated on bamboo (MgAl-LB) surface was further obtained by Transmission electron microscopy (TEM), and the typical TEM image shows that the MgAl-LDHs are present as ultrathin nanosheets (Figure 3(a))
The HRTEM image shows that the interplanar spacing is 0.25 nm (Figure 3(b)), which corresponds to the (012) plane spacing shown in the X-ray diffraction (XRD) pattern

Summary

Introduction

The demand for wood resources has gradually increased, but natural forestry is protected in China [1]. LDHs have a wide range of applications in many fields, such as catalysts [6], adsorbents [7], corrosion protection [8], and flame-retardant materials [9, 10]. Unlike the abovementioned application of LDHs as a wood fire retardant, MgAl-LDH coated on bamboo (MgAl-LB) was prepared by a one-step method, and the flame-retardant properties of MgAl-LBs prepared under different reaction times were analyzed. It was found through abrasion experiments that MgAl-LDHs synthesized on the surface of bamboo by this method had good abrasion resistance. The structure and chemical composition of MgAl-LDH on the bamboo surface were analyzed by Xray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, and elemental analyses. Sandpaper 30 cm Figure 1: Schematic diagram of the abrasion test

Materials and Methods

Results and Discussion

50 Untreated bamboo

Conclusion