Characterization and analysis of toughened bio-oil-basedphenolic foam prepared from poplar

Different catalysts (NaOH, H2O2, and NaOH/H2O2) was used to catalyze the conversion of poplar to bio-oil, which was then used to synthesize bio-oil-based phenolic foam (BPM). The bio-oil and BPM were characterized with GC-MS, FT-IR, TGA, optical microscope, extreme oxygen index analyzer, and universal testing machine. The results showed that the BPM had the better flame retardancy. The maximum limiting oxygen index was 37.7% found on the BPM prepared from NaOH/H2O2-catalyzed bio-oil. Compared with NaOH or H2O2, the NaOH/H2O2 presented synergistic catalysis in producing bio-oil with the highest phenolic content. The BPM synthesized with the bio-oil substitution at 20% showed the maximum compressive strength of 0.27 MPa. After the microscopic observation and TGA, it was found that BPM prepared from NaOH/H2O2 catalyzed bio-oil had more uniform and tiny bubbles, and higher thermal stability. In addition, a reasonable reaction mechanism was provided to explain the role of bio-oil in BPM synthesis.

Automated summary

Different catalysts (NaOH, H2O2, and NaOH/H2O2) were used to convert poplar to bio-oil and synthesize bio-oil-based phenolic foam (BPM). The BPM showed better flame retardancy, with the highest phenolic content achieved through NaOH/H2O2 catalysis. The BPM also exhibited higher compressive strength and thermal stability when prepared from NaOH/H2O2-catalyzed bio-oil.