摘 要随着当代经济与科技的发展,各个领域对高分子材料的防火性能的要求越来越高,环保法规的限制又使无卤阻燃的开发与应用成为高分子阻燃研究的大势所趋。有机硅阻燃剂作为阻燃剂的后起之秀,凭借其环保、高效、低毒、防熔滴的优点在阻燃领域得到了迅速发展。聚硼硅氧烷(PB)具有硼、硅两种阻燃元素,协效增强了有机硅阻燃剂的阻燃性能,拥有更好的阻燃效果和更广泛的适用性。
本文通过在PC/PBT合金中添加PB阻燃剂来增强该聚合物合金的阻燃性能,并且初步探究了PB对PC/PBT合金的阻燃机理。结果表明,PB可以显著提高PC/PBT合金的极限氧指数(LOI)。PC/PBT合金的LOI为22。8%,当在PC/PBT中添加10%PB时,合金的LOI达到了32。8%,提高了43。9%,显著提高了合金的阻燃性能。PB与二乙基次磷酸铝(PAL)复配使用后LOI没有进一步提高,说明PAL与PB不具有协同阻燃作用。锥形量热分析表明PB使PC/PBT合金体系的热、烟、CO、CO2释放速率降低,火灾性能指数提高,有效降低了燃烧的危险。聚硼硅氧烷的阻燃机理是按照凝聚相阻燃机理,即在燃烧过程中降低质量损失,促进残炭形成,使炭层紧密覆盖在基体表面,减少热辐射和氧气的扩散,从而达到阻燃的效果。90126
毕业论文关键词:聚硼硅氧烷; PC/PBT合金; 阻燃性能;阻燃机理
Abstract With the development of economy, science and technology, the fire resistance of polymer materials in various fields is required much higher。 Additionally, environmental protection law and regulation lead the development and application of halogen free flame retardant to be inevitable。 As a rising star of flame retardant, silicone flame retardant has been developed rapidly in the field of flame retardant by virtues, such as environmentally friendly characteristic, high efficiency, low toxicity and anti-dripping。 Polyborosiloxane (PB) contains boron and silicon, which can enhance the flame retardancy of silicone flame retardant, has better flame retardant effect and wider applicability。源Q于W优E尔A论S文R网wwW.yOueRw.com 原文+QQ75201,8766
The paper investigates the enhancement of flame retadancy of PC/PBT alloy by adding moderate amount of PB and the flame retardant mechanism of PB。 The experimental results show that PB can significantly improve the limiting oxygen index (LOI) of PC/PBT alloy。 When the content of PB was 10%, the LOI of the PC/PBT/PB alloy system reached to 32。8%, which increased by 43。7% than pure PC/PBT alloy。 PB and diethyl aluminium phosphate(PAL) have no synergistic flame retardancy, for adding PB/PAL compound could not increace LOI of the alloy system。 Cone calorimetry analysis shows that PB decreases release rate of heat, smoke, CO and CO2 in PC/PBT aloy system, and improves Fire performance index, so as to reduce the danger during combustion。 The flame reatardant mechanism of PB is based on the mechanism of condensed phase, which reduce mass loss during combustion, induce formation of residual char, make char tightly coat on the surface of alloy and reduce diffusion of thermal radiation and O2, thereby reach the result of flame retardancy。
Keyword: polyborosiloxane; PC/PBT alloy; flame retardany; flame retardant mechanism
目录
摘 要 4
1 引言 6
2 实验部分 8
2。1 主要原料和设备 8
2。2 阻燃合金的制备 8
2。3 测试与表征 9
3 结果与讨论 9
3。1 极限氧指数分析 9 聚硼硅氧烷对PC/PBT合金的阻燃作用:http://www.youerw.com/cailiao/lunwen_195915.html