Abstract:
Silicon-containing arylacetylene terminated by phenylacetylene (PTPSA) was synthesized by Grignard reaction, and the molecular structure was characterized and confirmed by Fourier transform-infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (
1H-NMR) and differential scanning calorimeter (DSC). A novel polytriazole (P-PTA3) resin was further synthesized through 1, 3-dipolar cycloaddition reaction between PTPSA and 1, 3, 5-tris(azidomethyl)-2, 4, 6-trimethylbenzene (TAMTMB). The unidirectional T700 carbon fiber reinforced P-PTA3 resin composite (T700/P-PTA3) was prepared by compression molding. The curing behaviors of the resin were monitored by FT-IR and DSC. The effects of molar ratio of monomers on the thermal properties of P-PTA3 resin were studied by dynamic thermos mechanical analysis (DMA) and thermogravimetric (TG) analysis. The storage stability of the resin and its tetrahydrofuran(THF) solution were evaluated by measuring the variation of the gel time against storage time. The gel time was measured under 90℃. The results show that the glass transition temperature (
Tg) of the cured P-PTA3 resin is 304℃ and 5% weight loss temperature (
Td5) is 341℃ as tested in nitrogen atmosphere (the molar ratio of the alkynyl and triazo is 1.1:1.0), and
Td5 of the samples with different molar ratios of the cured P-PTA3 resins is higher than 330℃. The P-PTA3 resin and its THF solution can be stored for more than 20 d and 40 d at 35℃ and 25℃, respectively. Correspondingly, the gel time of the resins at 90℃ is 24 min and 42 min, respectively, which presents a better storage stability than the currently existing polytriazole resin solution at the same storage temperature. The flexural strength and flexural modulus of T700/P-PTA3 composite at room temperature was 1 875 MPa, and 135.5 GPa, respectively, while the retention rate of bending strength was 75% under 180℃.