磷改性酚醛树脂的制备与性能

通过DOPO(9,10–二氢–9–氧杂–10–磷杂菲–10–氧化物)和多聚甲醛反应制备了含磷单体ODOPM(9,10–二氢–9–氧杂–10–磷杂菲–10–羟甲基–10–氧化物),并用于制备磷改性酚醛树脂。通过差示扫描量热(DSC)仪测试体系DOPO的反应程度,通过红外光谱表征ODOPM的结构,通过热重分析测试改性酚醛树脂体系的热行为,通过极限氧指数和垂直燃烧法测试树脂体系的阻燃性能,通过扫描电子显微镜观察树脂燃烧后残炭的微观形貌,并采用万能试验机测试树脂样条的强度性能。实验结果表明:实验成果制备得到目标产品ODOPM,随着含磷单体ODOPM含量的提高,酚醛树脂的阻燃性能随着提高,酚醛树脂的残炭量也随着提高。酚醛树脂通过凝聚相阻燃机理起到阻燃作用。当磷改性酚醛树脂的ODOPM单体含量为15%时,树脂的LOI值可以达到32.4%,并通过V–0垂直燃烧测试,并且磷改性酚醛树脂保持较好的强度。

Preparation and Properties of Phosphorus Modified Phenolic Resin

Phosphorus-containing monomer 9,10-dihydro-9-oxo-10-phosphaphenanthrene-10-methylol-10-oxide(ODOPM) was synthesized with 9,10-dihydro-9-oxo-10-phosphaphenanthrene-10-oxide (DOPO) and paraformaldehyde and then uesd to prepare phosphorus-containing phenolic resin. The reaction degree of DOPO was characterized by differential scanning calorimetry (DSC) test. The structure of the ODOPM was characterized by Fourier transform infrared spectroscopy (FTIR). The thermal behavior of modified phenolic resin was measured by thermogravimetric analysis(TG) and the flame retardancy of resin system was measured by limiting oxygen index (LOI) and UL-94 test. The micro-morphology of the char residue after combustion of resin was observed by scanning electron microscope (SEM). The strength property of resin spline was tested by universal testing machine. The results show that the target product ODOPM is prepared. The flame retardancy and content of residual char of the phenolic resin increase when the content of phosphorus-containing monomer ODOPM increases. The phenolic resin acts as a flame retardant through the condensed-phase flame retardant mechanism. When the content of ODOPM is 15%,LOI of the resin is 32.4%,pass the V-0 level of the UL-94 test,and also maintain good strength performances.