A flame retardant monomer 6-(2,5-bis ((4-vinylbenzyl) oxy) phenyl) dibenzo [c,e][1,2] phosphono-6-oxide (DOPVB) was synthesized by using 10-(2,5-dihydroxyphenyl)-10-hydro-9-oxy-10-phosphophenanthrene-10-oxide (DOPO-HQ) and 4-chloromethyl styrene (VBC) as raw materials. The DOPVB flame retardant was compounded with epoxy resin (EP) to prepare EP/DOPVB composites with different phosphorus contents, and their thermal, flame retardant, and dielectric properties were tested. The results show that the optimal synthesis conditions for DOPVB is that the molar ratio of reactants DOPO-HQ, VBC, and K2CO3 is 1∶2.2∶3.0, and the reaction time is 6 hours, then the yield is 74.55%. The EP/DOPVB cured material with a phosphorus content of 2.5% has the best comprehensive performance, its glass transition temperature is 130.4℃, which is 45.21% higher than that of pure EP. The dielectric constant is 2.98 and the dielectric loss factor is 0.005 03, which is 21.99% and 72.16% lower than that of pure EP, respectively. The vertical combustion test of the composite material prepared from the cured material reaches V-0 level, with a limit oxygen index of 67.4%.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |