星型无卤阻燃剂改性粘胶纤维的制备及其性能

针对粘胶纤维的可燃性带来安全隐患的问题,优选含有六元环结构的六氯环三磷腈作为功能单体,设计合成了一种同时含有磷、氮、硅三元阻燃元素的星型无卤阻燃剂。将该阻燃剂添加到粘胶中,采用湿法纺丝工艺制备了阻燃改性粘胶纤维。借助傅里叶红外光谱仪、X射线光电子能谱仪、热重分析仪、热重-质谱联用系统等对阻燃改性粘胶纤维的结构和性能进行分析。结果表明:改性后粘胶纤维的阻燃性能明显提高,且具有一定的耐洗性;与未改性粘胶纤维相比,其在氮气氛围下800 ℃时的残炭量从12.5%提高到31.2%;在改性粘胶纤维燃烧过程中,可燃性气体释放量明显降低并产生大量膨胀炭层,说明阻燃剂在气相和凝聚相发挥阻燃作用。

Preparation and properties of viscose fibers modified with star-shaped halogen-free flame retardants

Aiming at the potential safety hazard caused by the flammability of viscose fibers, phosphonitrilic chloride trimer containing a ring structure was selected as a functional monomer to design a star-shaped halogen-free flame retardant that combines phosphorus, nitrogen, silicon ternary flame retardant elements. The flame retardant was added to the viscose, and then the flame retardant modified viscose fibers was prepared through wetting spinning. The structures and properties of the modified viscose fibers were characterized by means of Fourier infrared spectroscopy, X-ray photoelectron spectroscopy, thermogravimetric analyzer, and thermogravimetric-mass spectrometry system. The results show that the flame retardancy of the modified viscose fibers was improved while the fibers maintaining the durability. In nitrogen atmosphere, its char residue rate at 800 ℃ increased from 12.5% to 31.2% compared with the unmodified viscose fibers. During the combustion process of the modified fibers, the release of combustible gas was significantly reduced and abundant expanded carbon layer was produced. The flame retardant operated in condensed phase and gas phase.