Synergistic Effect of APP and TBC Fire-Retardants on the Physico-Mechanical Properties of Strandboard.

Feiyu Tian,Deliang Xu,Xinwu Xu

doi:10.3390/ma15020435

Abstract

This study explored the feasibility of fabricating fire-retardant strandboard with low mechanical properties deterioration to the physico-mechanical properties. A hybrid fire-retardant system of ammonium polyphosphate (APP) and 1,3,5-tris(2,3-dibromopropyl)-1,3,5-triazinane-2,4,6-trione (TBC) was investigated. Thermogravimetric analysis results show that both APP and TBC enhance the thermal stability and incombustibility of wood strands. An infrared spectrum was applied to investigate the effect of flame retardants on the curing behaviors of polymeric diphenylmethane diisocyanate (PMDI) resin. Based on the results of limiting oxygen index (LOI) and Cone calorimetry (CONE), APP and TBC both lead to a higher fire retardancy to strandboard. It is worth mentioning that the two flame retardants lead to evidently differential influences on the modulus of rupture (MOR), modulus of elasticity (MOE), internal bond (IB), and water-soaking thickness swelling (TS) properties of strandboard. Hence, a hybrid flame retardant is prominent in manufacturing strandboard with both good fire retardant and satisfying physico-mechanical properties.

Highlights

Considering their low-carbon advantages and constructional friendliness, wood constructions are encouraged by Chinese administrations with commercially engineered wood products quantitatively available.Fire safety tends to be a key factor in wood construction
A valuable finding is that ammonium polyphosphate (APP) and TBC lead to differential influences on the bending and internal bond properties of strandboard
Fourier transform infrared (FTIR) indicated that the addition of APP would make polymeric diphenylmethane diisocyanate (PMDI) curing in advance, and the macroscopic mechanical performance was the decrease of internal bond (IB) strength

Summary

Introduction

Considering their low-carbon advantages and constructional friendliness, wood constructions are encouraged by Chinese administrations with commercially engineered wood products quantitatively available (e.g., oriented strandboard or OSB [1,2], glued laminated timber or glulam, etc.). Fire safety tends to be a key factor in wood construction. In 2020, there were 109,000 residential building fires in China, resulting in 1416 death and injuries [3]. In 2018 alone, there were 379,600 residential building fires across the country, resulting in 14,315 death and injuries [5]. The materials for wood constructions, e.g., OSB, need to be technically treated with fire retardants, such as brominated fire-retardants (BFRs) [6,7,8]

Methods

Results

Conclusion