聚丙烯腈纤维/织物表面阻燃改性、阻燃机理研究

It is a major issue concerned by the countries around the world to develop the halogen-free fire retarded polyacrylonitrile (PAN) fiber/fabric.The effective solution to the question is to effectively promote the cyclization reaction of nitrile group in PAN fiber/fabric and the formation of physical shielding. In view of the defect of the difficult industrial implementation of halogen-free fire retardant PAN fiber/fabric, the project will firstly take advantage of UV-induced graft polymerization technique to implement graft polymerization of hydroxy group contained functional monomer onto PAN fiber/fabric, followed by the phosphorylation of the hydroxy of the grafted chain to obatin halogen-free fire retardant PAN fiber/fabric containing phosphorus pendant group. Secondly, Sol-gel coating technique will be used to achieve PAN fiber/fabric halogen-free fire retardant coating. Thirdly, UV-induced graft polymerization and sol-gel fire retardant coating techniques are combined to obtain halogen-free fire retardant PAN fiber/fabric. we make full use of the superiority of the combined modern analytic techniques of thermogravimetry-Fourier transform infrared spectroscopy, thermogravimetry-mass spectrometry, pyrolysis gas chromatography-mass spectrometry and cone calorimeter and cross-polarization magic angle spinning solid nuclear magnetic resonance to obtain the thermal decomposition mechanism, fire retardant mechanism, the combustion behavior and the cyclization mechasim of the halogen-free fire retarded PAN fiber/fabric in detail. The project aims to pioneers a surface fire retardant method to develop the halogen-free fire retarded PAN fiber/fabric, to propose a novel idea to develop halogen-free fire retardant PAN fiber/fabric, and it will be the foundation for the industrialization of the halogen-free fire retarded PAN fiber/fabric.

聚丙烯腈(PAN)纤维/织物的无卤阻燃是世界各国长期关注的亟待解决的重大课题，能有效促进PAN纤维/织物中氰基（CN）环化成炭反应及形成物理屏障是成功解决此问题的关键。鉴于此，本项目首先采用紫外光接枝技术将含羟基的功能单体接枝到PAN纤维/织物表面，继而通过对接枝链中羟基的磷酰化反应，获得侧链含磷的无卤阻燃PAN纤维/织物；其次，利用溶胶-凝胶涂层技术实现PAN纤维/织物无卤阻燃涂层；第三，将紫外光接枝与溶胶-凝胶阻燃涂层技术相结合进行PAN纤维/织物无卤阻燃。借助热重-红外、热重-质谱、裂解气质联用、锥形量热和交叉极化魔角旋转固体核磁等分析技术，掌握无卤阻燃PAN纤维/织物的热分解及阻燃机理和燃烧行为，揭示阻燃PAN纤维/织物的环化机理。本项目旨在开发一种通过表面阻燃技术实现PAN纤维/织物的高效无卤阻燃，提出一种PAN纤维/织物无卤阻燃改性的新思路、新方法，为其工业化奠定基础。

聚丙烯腈（PAN）纤维享有“人造羊毛”的美誉，在纺织行业中占有重要地位，然而，该纤维的极限氧指数（LOI）值仅为18%左右，由其纺织成的织物极易燃烧而引发火灾，所以，开发阻燃PAN纤维/织物具有重大的现实意义。目前为止，产业化的阻燃PAN纤维仅有腈氯纶，该纤维虽具有良好的阻燃性能，但由于该纤维中大量含卤成分的存在，使得该纤维一旦燃烧会释放大量烟雾及腐蚀性卤化氢气体，极大地限制了该纤维的广泛使用。因此，PAN纤维及其织物的无卤阻燃是世界各国长期关注的亟待解决的重大课题。鉴于此，本项目为制备无卤阻燃PAN纤维/织物，采用表面阻燃改性技术进行了以下研究：1）采用紫外光接枝技术将功能单体接枝到PAN织物表面，继而通过对接枝链的化学改性，获得侧链含磷、氮的无卤阻燃PAN织物；2）针对PAN织物的直接表面化学改性，制备了耐久阻燃PAN织物；3）利用溶胶-凝胶涂层技术对PAN织物进行磷掺杂的有机-无机硅杂化涂层，实现PAN织物的无卤阻燃；4）以溶胶-凝胶与层-层自组装相结合技术，赋予PAN织物良好的阻燃性；5）将紫外光接枝与溶胶-凝胶阻燃涂层技术相结合进行了PAN织物无卤阻燃；6）采用共混增强与表面改性相结合技术制备高效高强耐久阻燃PAN纤维；7）借助热重-红外、裂解气质联用、锥形量热等分析技术，掌握无卤阻燃PAN纤维/织物的热分解及阻燃机理和燃烧行为；8）研究了阻燃PAN纤维/织物的阻燃耐久性。本项目验证了表面阻燃改性技术在制备无卤阻燃PAN纤维/织物中的可行性，实现了PAN纤维/织物的耐久无卤阻燃，阻燃改性后的PAN纤维织物30次水洗后其极限氧指数（LOI）值仍高达30%以上，热释放速率峰值（pHRR）最大可降低90%以上，显示出优异的阻燃性能。本项目开发了一种PAN纤维/织物无卤阻燃改性的新思路、新方法，避免了常规共聚法及共混法制备阻燃聚丙烯腈的缺陷，实现了改性单元与PAN纤维/织物间的良好化学键合，从而赋予了PAN纤维/织物良好的阻燃耐久性，为其工业化奠定了基础。