耐高温杂化阻燃剂/改性红磷阻燃半芳香尼龙的研究

Semi-aromatic Polyamide Flame-retarded by Modified Red Phosphorus and BM@Al-PPi Hybrid with High Temperature Resistance

将自制的耐高温勃姆石@苯基次膦酸铝杂化阻燃剂(BM@Al-PPi)与市售改性红磷(MRP)复配制得一种可用于半芳香尼龙PA6T/DT(HTN)的耐高温高效阻燃体系.保持阻燃剂15 wt%的总添加量不变时,MRP的添加量仅为5 wt%即可赋予HTN垂直燃烧V-0级别,极限氧指数为29.8%.锥形量热测试及其燃烧残余物研究表明,MRP阻燃HTN材料以气相阻燃作用为主,抑制热释放效果不佳且烟释放明显增加;而BM@Al-PPi的凝聚相交联成炭作用可同时抑制热释放与烟释放.结合裂解气相色谱质谱联用(Py-GC-MS)分析,给出了HTN/BM@Al-PPi/MRP体系的阻燃机理.BM@Al-PPi与MRP结合使得残炭质量显著提高,同时兼具气相作用,达到了较好的阻燃效果.

An inorganic-organic hybrid named boehmite@ aluminum phenylphosphinate （BM@ A1-PPi） with high temperature resistance was used to flame retard semi-aromatic polyamide （HTN） in combination with a modified red phosphorus （MRP） flame retardant. The flame-retardant property and mechanism of the resulting flame-retardant HTN systems were investigated. When the total Content of the flame retardants was 15 wt% ,the HTN could achieve UL-94 V-0 rating at the mass ratio of BM@ A1-PPi to MRP ranging from 1：4 to 2： 1, and the limiting oxygen index was raised to 30.0% from 23.5%. Cone calorimetry was used to investigate the combustion behaviour of flame-retardant HTN samples. For HTN/15% MRP system, MRP reduced the heat release of HTN, meanwhile a great mass loss rate during combustion led to a 30% lower effective heat of combustion （Av-EHC） and much higher smoke release than those of neat HTN,which supported that the MRP mainly work in the gas phase. With addition of 15 wt% （HTN/15% BM@ A1-PPi）,more compact burning char was obtained,reducing the heat release and suppressed the smoke production,and BM@ A1-PPi played a role in condensed phase. The HTN flame-retarded by the binary flame retardants was endowed lower heat release values （such as PHRR,THR and MAERH） and lower smoke production than by MRP. In particular the total heat release of HTN/10% BM@ A1-PPi/5% MRP decreased by 60%. These results indicated that there was a synergistic effect between BM@ A1-PPi and MRP for flame-retarding HTN. The function of char forming and the synergistic flame-retardant mechanism in condensed phase were investigated by SEM-EDX,in which a uniform distribution of phosphorus element both in the outer and inner surfaces of the char layers was observed,suggesting that a continuous and compact char was formed, and the heat flow and fuel could be blocked effectively. Furthermore,the corresponding gaseous phase flame-retardant mechanism was put forward via pyrolysis gas chromatography coupled with mass spectrometry （Py-GC-MS）