Open AccessBionic boron/silicon‐modified phenolic resin system with multifunctional groups: synthesis, thermal properties and ablation mechanism
Author(s) -
Wang Fengyi,
Huang Zhixiong,
Guo Zhiguang
Publication year - 2018
Publication title -
biosurface and biotribology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.497
H-Index - 4
ISSN - 2405-4518
DOI - 10.1049/bsbt.2018.0013
Subject(s) - materials science , charring , silicon , boron , composite material , thermal stability , formaldehyde , graphite , composite number , layer (electronics) , chemical engineering , ablation , organic chemistry , chemistry , engineering , metallurgy , aerospace engineering
A kind of silicon‐and‐boron‐modified phenolic–formaldehyde resin (SBPF) with excellent thermal stability was fabricated via a simple two‐step method and used for the matrix of ablation materials. The structure and thermal stability of the modified phenolic–formaldehyde resins (PFs) were characterised. The results showed that boron and silicon elements have been incorporated into SBPF in the form of a chemical bond. Meanwhile, the cured products showed an increase in graphite structure and a decrease in disordered structure due to the incorporation of boron and silicon. Compared with the ordinary phenolic resin, the initial thermal degradation temperature and charring yield at 800°C of SBPF increased by 73°C and 15 wt%, respectively. Further, the modified PFs, nano‐Al 2 O 3 powders, glass powders and vitreous silica fibres were used to obtain a novel ceramizable phenolic moulding composite. The morphology, chemical composition and ablative characteristics of the composites were explored. The results showed that a compact and homogeneous SiO 2 –Al 2 O 3 layer formed on the ablated surface and protected the carbonised matrix and fibres from further oxidation. Compared with the ordinary PF composites, the SBPF composites showed a highly decreased linear/mass ablation rates, indicating the synergistic effect of boron and silicon modification on the enhanced ablation property.