膨胀炭质层品质对IFR体系的阻燃效果起着决定性作用。本项目针对IFR体系膨胀炭质层存在的残碳量低、致密性和热稳定性差等品质问题，利用木质素含碳量高、苯环结构多且成炭性好等特点以及木质素可以诱导聚合物成炭，形成坚硬炭层，提高聚合物热稳定性等特性，提出以木质素替代季戊四醇等作炭源，构建基于木质素的IFR体系，以改善膨胀炭质层的品质。项目研究不同类型木质素的热稳定性，探讨其与酸源、气源间的匹配性；从宏观和微观结构、元素组成及化学特性等方面表征基于木质素的膨胀炭质层的品质，研究木质素对膨胀炭质层残碳量、致密性、隔热性、热稳定性及阻燃性的影响。本项目旨在构建基于木质素的IFR体系及相关理论，揭示木质素对膨胀炭质层品质和性能的影响机制及协同作用机理，建立基于锥形量热仪法的膨胀炭质层品质评价方法。项目通过以生物质原料替代化石原料，实现具有“绿色阻燃”特征的技术创新，以推动材料阻燃技术的进步。

Foamed charring layer of the IFR system is crucial for flame retardent properties, but it still has some problems. For example, the amount of the residual carbon is relatively low; the structure compactness is unsatisfactory and the thermal stability is poor. In this proposal, we use lignin, which is rich of the carbon atoms and hydroxyl and could induce the polymer into carbon to form a hard charring layer, to improve the quality of the foamed charring layer of the new type IFR system as an charring agent. The thermal stability of the lignin as carbon source is characterized by the thermal gravimetric analysis method and the mutual matches among the lignin, acid source and gas supply are explored. Methods of modern analytical tools, the macro and micro, are used to characterize the quality of the foamed charring layer of the IFR system in order to research the influence of lignin on the amount of the residual carbon, structure compactness, heat insulation, thermal stability of the foamed charring layer and flame retardant properties of the IFR system. The objective of the project is to construct the lignin-based IFR system and related theories, to uncover the synergy mechanism and the influence law of the lignin in the system, and to establish a evaluation methods based on the cone calorimeter method on the quality of the foamed charring layer of the IFR system. The significance of the project is to promote technological progress in the field of fire retardant by the technical innovation of “Green flame retardant” using biomass to replace fossil raw materials.