【作者】 章涛；

【导师】 胡源； 阚永春；

【作者基本信息】 中国科学技术大学 ， 高分子化学与物理， 2020， 硕士

【摘要】 聚合物材料因其密度小、耐腐蚀性、加工工艺简单、无毒、卓越的力学性能等,而被广泛地应用于住宅、化工、电子、电力工业和交通运输设备等人们生活和生产的通用材料。但易燃性的聚合物材料无疑是增加了火灾的危险性,例如,燃烧过程中会产生大量的CO、NO2、SO2等有毒烟气会严重威胁着人类生命安全,同时也会造成严重的财产损失。此外,聚合物材料在燃烧过程中易发生熔滴,导致火焰扩散。聚脲弹性体涂料被认为是用于战略应用(特别是减震和防弹保护)的聚合物材料。鉴于其优异的减震性能和弹道防护性能,由聚醚胺和异氰酸酯的快速逐步聚合反应合成的聚脲在国防军工项目(例如坦克底盘、防弹头盔、防护装甲)、混凝土涂料、管道防腐、储罐衬里和建筑物防水中得到了广泛应用。本论文在综述阻燃聚脲复合材料研究的基础上,针对聚脲材料的阻燃、热解与燃烧特性做了如下研究:合HPPU阻燃剂对PUA燃烧热解的影响、HAP对PUA阻燃和力学性能的影响,SiO2/PUA复合涂层对木材阻燃和防火的影响。通过对材料进行各种物性和化学结构的表征,得到了材料的化学结构、表面形貌、热稳定性和阻燃性。然后,通过锥形量热仪和火焰燃烧实验,对阻燃机理进行探索,具体工作如下:1.以THPO和TDI为原料,在室温下进行缩聚反应,合成了一种HPPU阻燃剂。利用NMR和FT-IR对HPPU的化学结构进行了表征。通过TGA对HPPU和聚磷酸铵(APP)的热稳定进行了研究,并且对其复配的PUA复合材料从初始降解温度,和成炭量对其阻燃效果进行了分析。此外,还利用实时红外(RT-FTIR)对PUA复合材料在不同温度下,凝聚相热解物质的变化进行了分析。2.无机纳米材料增强PUA,采用原位聚合技术,将聚碳二苯甲烷二异氰酸酯(MDI-100L)与聚四甲氧基二氨基苯甲酸酯(PTMO,P1000)共价连接,制备了羟基磷灰石(HAP)/PUA纳米复合材料。通过观察纳米复合材料的分散性和界面作用,研究了纳米复合材料的性能增强。力学性能方面,拉伸试验结果表明,添加0.2 wt%HAP纳米棒的PUA/HAP纳米复合材料的抗拉强度提高了52.4%。SEM、EDSM、ATR-FTIR和XRD测试结果表明,HAP的分散以及HAP纳米棒与PUA之间氢键相互作用力是PUA复合材料在外部动态载荷下,刚度减弱的重要因素。此外,HAP纳米棒的加入可以有效地抑制了 PUA的自硬现象,并且随着HAP含量的增加而降低。3.木制材料是现代家居中经常使用的材料,尤其是靠近明火的厨房家具,其表层的防火能力,决定着房屋的安全。传统无机涂料工艺复杂,成本高。同样,有机绝缘涂层也因其结构完整性和耐火性差而受到限制。在此,我们开发了一种具有隔热和优异防火性能的无机/有机复合涂料。异氰酸酯和硅酸钠通过聚合形成最终的Si-O-Si网络结构。LOI测试的结果显示该涂层具有非常卓越的防火性能。根据锥形量热仪测试的结果显示:5 min内的总热释放量小于8 MJ·m-2,表明了涂层使得木材赋予了极佳的防火性。通过丁烷火焰燃烧30 min后,涂膜的木材仍保持其结构完整性,未暴露火焰的一侧仅180℃。作为一种快速喷涂成型涂料,它在防火材料领域从实用性和隔热性两方面都显示出巨大的潜力。更多还原

【Abstract】 Due to its low production cost,low density,non-toxic,corrosion-resistant,easy processing,superior mechanical properties,polymer materials have been widely used in residential,chemical,electronic,power industry,transportation equipment and other people’s lives and production of general materials.However,the flammability of polymer materials increases the risk of fire.For example,a large number of carbon monoxide and toxic gases will be produced in the combustion process,which seriously threatens the safety of human property and life.In addition,polymer materials are prone to drop during combustion,which leads to flame diffusion.Polyurea elastomer coatings are considered to be polymer materials for strategic applications,especially shock absorption and bullet proof protection.In view of its excellent shock absorption performance and ballistic protection performance,the polyurea synthesized by the rapid and gradual polymerization of polyether amine and isocyanate has been widely used in national defense and military projects(such as tank chassis,bullet proof helmet,protective armor),concrete coating,pipeline anticorrosion,tank lining and building waterproofing.In this dissertation,based on the review of the research on flame retardant polyurea polymer composite materials,study on the synthesis of hyperbranched flame retardants,flame retardant properties of polyurea composite materials,and fire-retardant coatings prepared by hybridization of isocyanate and inorganic materials.Through the technical characterization of various physical properties and chemical structure of the material,the chemical structure,surface morphology,thermal stability and flame retardancy of the material are obtained.Then,through small-scale and large-scale combustion experiments,the flame retardant mechanism was investigated.The specific work is as follows:1.Using THPO and TDI as raw materials,a polycondensation reaction was carried out at room temperature to synthesize a HPPU flame retardant.The chemical structure of HPPU was characterized by NMR and FT-IR.The thermal stability of HPPU and APP was studied by TGA,and the flame retardant effect of PUA composites was analyzed from the initial degradation temperature and the carbonaceous residue.In addition,real time Fourier transform infrared spectra(RT-FTIR)was also used to investigate the changes of the pyrolysis substances in the condensed phase of PUA composites at different temperatures.2.Inorganic nano-materials reinforced PUA.In-situ polymerization technology was used to covalently linking polycarbodiphenylmethane diisocyanate(MDI-100L)and polytetramethoxydiaminobenzoate(PTMO,P1000)to prepare hydroxyapatite HAP/PUA nanocomposite material.By observing the dispersion and interface effects of nanocomposites,the enhancements of composites properties were studied.In terms of mechanical properties,the tensile test results showed that the tensile stress of PUA/HAP nanocomposites with 0.2 wt%HAP nanorods increased by 52.4%.SEM,EDSM,ATR-FTIR and XRD test results show that the dispersion of HAPs and the hydrogen bonding interaction between HAP nanorods and PUA are important factors for the increase in tensile strength and the decrease in rigidity of PUA composites.In addition,the addition of HAP nanorods can effectively suppress the self-hardening phenomenon of PUA with the increase of HAP content.3.Doors of high-rise buildings,furniture in kitchen and other places easily accessible to fire all require woods with a high flame resistance and a low thermal conductivity.Traditional inorganic coatings are restricted by complex process and high cost.Similarly,organic insulation coatings are limited by their poor structural integrity and fire resistance.Herein,we developed an inorganic/organic composite coating with a lower thermal conductivity and brilliant fire resistance.Isocyanate and sodium silicate are polymerized to form the final Si-O-Si network structure.The results of the LOI test showed that the coating has very excellent fire resistance,and its value can reach 48.0 vol%.According to the fire resistance standard of the CC test,the coating can make wooden materials reaching the fire resistance standard.After exposed to butane flame 30 min,coated wood still maintained its structural integrity with only 180℃ on the non-exposed side.As a fast spray-formed coating,it exhibits a great potential in the field of fire-safe materials,both from practicality and thermal insulation.更多还原