Compressible, Flame-Resistant and Thermally Insulating Fiber-Reinforced Polybenzoxazine Aerogel Composites.

Yunyun Xiao,Liangjun Li,Junzong Feng,Fengqi Liu,Jian Feng,Sizhao Zhang,Yonggang Jiang

doi:10.3390/ma13122809

Abstract

The preparation of novel polymer aerogel materials with enhanced flame-retardancy, superior thermal insulation and mechanical strength is of great practical significance in energy-savings and fire-prevention for buildings. Herein, we reported the fiber-reinforced polybenzoxazine (PBO) aerogel composites with flame retardance and thermal insulation, which were prepared under room temperature and atmospheric pressure, and using 4,4′-diaminodiphenlymethane (MDA) benzoxazine monomer as the raw material and oxalic acid (OA) as the catalyst. Several outstanding attributes were achieved in the aerogel composites, such as relatively low thermal conductivity (0.069 W/m·K at 105 Pa, 0.031 W/m·K at 5 Pa), high limiting oxygen index (LOI) up to 32.5, and enhanced mechanical properties. It can be compressed to more than 80% of the deformation without obvious cracks, and shows high compressive modulus and specific modulus (20.69 MPa and 5.05 × 104 N·m/Kg, respectively). All the excellent comprehensive properties mean that fiber-reinforced PBO aerogel composites have broad application prospects in the fields of flame retardancy and thermal insulation.

Highlights

Aerogels have been widely used in civil, residential and industrial buildings, due to their low density, and excellent thermal insulation and acoustic insulation [1,2,3]
The density of the fiber-reinforced PBO aerogel composites was calculated based on the measured volume and weight
The compressive strength of phenolic aerogel composites with a similar density at 3%, 5%, 10% and 20% strain are (LOI) respectively was used to measure the flame-retardancy the composite

Summary

Introduction

Aerogels have been widely used in civil, residential and industrial buildings, due to their low density, and excellent thermal insulation and acoustic insulation [1,2,3]. It is still a challenge to prepare flame-retardant and thermally insulating polymer aerogels with superior mechanical properties. We reported on PBO aerogels derived from a 4,40 -diaminodiphenlymethane (MDA) monomer, prepared by supercritical drying and using HCl as the catalyst under room temperature, and systematically studied their structure, thermal insulation and mechanical properties [23]. There are few reports on the use of fiber reinforcement to improve the strength and flame-retardancy of PBO aerogels, or to overcome the mismatch of inorganic components, such as particles and whiskers, with the PBO aerogel matrix. After compounding with PBO aerogels that are self-extinguishing and have low thermal conductivity, the composite aerogels can ensure low density and excellent mechanical properties, while further improving flame-retardancy

Experimental Section

Discussion

Pa initially

Conclusions