高相对分子质量膨胀型阻燃剂的合成及在聚氨酯阻燃中的应用

Synthesis and Application of High Molecular Weight Intumescent Flame Retardant in Thermalplastic Polyurethanes

为了改善热塑性聚氨酯的阻燃性能,并尽量减小阻燃剂对其力学强度的影响,本文以三氯氧磷、季戊四醇(PER)、硫氰酸钾(KSCN)和1,3-丙二胺为原料合成了一种螺环状膨胀型高分子阻燃剂ISPDP,并采用核磁共振氢谱、红外光谱和凝胶渗透色谱对其结构进行了表征。热失重分析表明,ISPDP对热塑性聚氨酯具有明显促进成炭的作用。通过极限氧指数(LOI)和垂直燃烧(UL-94)对阻燃热塑性聚氨酯(ISPDPTPUs)体系进行燃烧测试,结果表明随着ISPDP添加量的增加,LOI增长显著,当达到最佳添加量15%时,LOI可以达到33,垂直燃烧等级为UL-94 V-0。扫描电镜对ISPDPTPUs燃烧后炭层表面研究结果显示,随着ISPDP添加量的增大,炭层表面变得更加致密。力学性能测试结果显示,ISPDP最优添加量15%时其拉伸强度略有增加,弹性模量大幅度增强,断裂伸长率仍可保持65%。

In order to improve flame retardant properties of thermoplastic polyurethanes（ TPU）,and to minimize effect on mechanical strength,a novel intumescent flame retardant ISPDP with high molecular weight was synthesized using pentaerythrite,prophorus oxychloride（ POCl3）,potassium thiocyanate（ KSCN） and 1,3-diaminopropane. The structure of ISPDP was characterized via1H-NMR and FT-IR,and the molecular weight was characterized by gel permeation chromatography（ GPC）. The results of TGA indicate that ISPDP could significantly improve the char yield of TPU.Limiting oxygen index（ LOI） and vertical burning were used to test its flame-retardant properties. ISPDPTPU with 15%ISPDP could achieve the optimal flam retardancy,of which the LOI value is 33% and UL-94 rating is V-0. The microstructures of the char residues for pure TPU and ISPDPTPUs are observed via SEM. The results show that the residual char of ISPDPTPU with optimal loading content is dense and continuous. Adding the optimal loading content of ISPDP could improve tensile modulus and ultimate tensile strength of TPU,and the elongation of ISPDPTPU（ 15%） could remain 65% of that of TPU0.