表面化学接枝改性阻燃棉织物的制备与性能

采用高碘酸钠对棉织物表面进行选择性氧化生成醛基，选取乙二胺与醛基反应，通过膦氢化加成反应将阻燃剂亚磷酸二甲酯接枝到棉织物表面，最后通过三羟甲基三聚氰胺对棉织物表面进行接枝改性，制备了含三羟甲基三聚氰胺/乙二胺/亚磷酸二甲酯阻燃棉织物.通过傅里叶红外光谱（FTIR）对改性后棉织物的结构进行了表征，通过极限氧指数（LOI）测试研究了其阻燃性能，通过锥形量热测试研究了其燃烧行为，通过在40℃皂水中洗涤10次考察了其耐水性能，通过扫描电子显微镜测试了其表面及燃烧后炭层的形貌.研究结果表明，经表面改性后，棉织物的LOI值由（19.5±1.0）%提高到了（43.1±1.0）%，经耐水洗测试后，LOI值仅下降至（42.6±1.0）%，保持了非常好的阻燃性能，表明通过表面接枝方法制备的三羟甲基三聚氰胺/乙二胺/亚磷酸二甲酯阻燃棉织物具有非常好的耐水洗性能.表面阻燃改性提高了棉织物在燃烧过程中的成炭性能，形成的连续膨胀的炭层较好地保护了内部织物，抑制了织物的降解和燃烧，从而提高了棉织物的阻燃性能.

Preparation and Properties of Flame Retardant Cotton Fabric by Surface Chemical Grafted Modification

Cotton fabric was firstly selective oxidized by sodium periodate to formed aldehyde groups, ethylenediamine was chosen and reacted with aldehyde groups. Then, the flame retardant dimethyl phosphite was grafted on cotton fabric surface by phosphine hydride addition reaction. Finally, trimethylolmelamine was grafted on the surface of cotton fabric and the phosphorus-nitrogen containing flame retardant cotton fabric was obtained. The structure of the modified cotton fabric was characterized by Fourier transform infrared spectroscopy(FTIR). The flame retardancy of the modified cotton fabric was evaluated by limiting oxygen index(LOI) tests, and the combustion behavior was investigated by cone calorimeter tests. The water washing durability of the modified cotton fabric was investigated by washing in soap water for 10 times at 40℃, and the surface morphology was studied by scanning electron microscopy. The result indicated that the LOI value of the obtained modified cotton fabric dramatically increased from (19.5±1.0)% for pure cotton fabric to (43.1±1.0)%, and after washing test, the LOI value slightly decreased to (42.6±1.0)%, which indicated that the obtained cotton fabric remained superior flame retardancy and possessed excellent washing durability. The surface chemical grafted modification for cotton fabric enhanced the char-forming ability of cotton fabric during combustion, and the formed intumescent char layer protected the inner cotton fabric from further degradation and combustion, thus enhanced the flame retardancy of cotton fabric.