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1、染染 整整 工工 艺艺 原原 理理 纺织物的前处理和后整理纺织物的前处理和后整理董 永 春 教授纺 织 学 院 天 津 工 业 大 学1第九章 阻燃整理第一节 引言 纤维制品如服装、装饰织物、产业用布易于引发火灾，需要进行 阻燃整理。不同的纺织品有不同的阻燃要求。 美、英国调查：近一半的火灾是由纺织品引起的，德国调查：约 20%是由装饰布引起的。 阻燃产品最初是仅用于军用特品，继而用于运输工具、公共场所 的装饰布和工作服，近年来发达国家在衣服、家用织物上亦要求 阻燃性。 值得指出的是阻燃整理不能使纤维不燃烧，而是降低其可燃性， 离开火源后能迅速停止燃烧。阻燃是相对的。2第二节 关于纤维燃烧的分
2、析vv 燃烧过程中的三个要素：纤维、燃烧过程中的三个要素：纤维、OO2 2和热量。和热量。3vv 纤维的燃烧性纤维的燃烧性 以极限需氧指数（极限需氧指数（Limiting Limiting Oxygen Oxygen Index Index LOI LOI or or OIOI）指样品在 氮、氧混合气环境中保持烛状燃烧所需的氧气的最小体积分数。 标准：不燃性：LOI 35，难燃性： LOI = 2634可燃性 LOI = 2026， 高燃性： LOI 20大气中O = 21%（V），因此一般民用纤维都是可燃性纤维。LOI：棉 17-19，涤纶 20-22 羊毛 24-264vv 影响纤维燃烧的
3、因素影响纤维燃烧的因素o化学组成中的H含量，LOI。o组成中N含量，LOI。o组成中的阻燃元素Cl、Br、 P、S和 Sb ，阻燃性。o分子结构刚性好、规整；结晶度、取白度高，燃烧性。o炭化倾向，燃烧性。5THEORY OF COMBUSTIONTHEORY OF COMBUSTIONq When solid materials are heated, physical and chemical changes occur at specific temperatures depending on the chemical make- up of the solid. q Thermoplas
4、tic polymers soften at the glass transition temperature (Tg), and subsequently melt at Tm. At some higher temperature (Tp), both thermoplastic and non-thermoplastic solids will chemically decompose (pyrolyze) into lower molecular weight fragments. q Chemical changes begin at Tp and continue through
5、the temperature at which combustion occurs (Tc). These four temperatures are very important when considering the flame resistance of fibers. 6q Another important factor in combustion is the Limiting Oxygen Index (LOI). q This is the amount of oxygen in the fuel mix needed to support combustion. q Th
6、e higher the number, the more difficult it is for combustion to occur. Values for these parameters for various fibers are given in Table 22. 78q For non-thermoplastic fibers, Tp and/or Tc is less than Tg and/or Tm, however for thermoplastic fibers Tp and/or Tc is greater than Tg and/or Tm.q Natural
7、fibers are not thermoplastic, therefore when they are subjected to a heat source, pyrolysis and combustion temperatures are encountered before softening or melting temperatures are reached and eventually ignite. q On the other hand, low melting thermoplastic fibers will melt and drip away from the f
8、lame before pyrolysis and combustion temperatures are reached. However if the melt doesnt shrink away from the flame front, pyrolysis and combustion temperatures are eventually reached and ignition will occur.9第三节 阻燃机理q 覆盖论：覆盖保护作用，阻燃剂如硼砂/硼酸在高温下发生熔融现 象，形成玻璃状保护膜，一方面是隔断外界氧气进入，另一方面 是阻止可燃性气体向外界扩散，达到对纤维的覆
9、盖保护作用。q 气体论：阻燃剂在高温时放出不燃性气体，将燃烧放出的可燃性 气体冲淡到燃烧浓度以下，即具有气体稀释作用。不同气体的稀 释作用如下列顺序： N2CO2SO2NH3 。q 吸热论： 阻燃剂在受热时发生吸热反应，如分解、熔融、升华、 相变等，使纤维迅速散热，达不到燃烧温度。10q 催化脱水论：阻燃剂改变纤维的热裂解历程，发生脱水，阻止可 燃性物质产生，固体炭量增加，抑制有焰燃烧。q 熔滴作用：阻燃剂降低熔融温度，形成熔滴，离开燃烧体系。q 吸收游离基作用（气相阻燃理论）：阻燃剂作为游离基的转移体 ，使它们失去活性，阻止游离基反应的进行。卤化烃有此作用： RX + H HX + R 客观
10、而言，在实际中，阻燃剂的阻燃作用是多种机理的复合作用 。 其中覆盖论、气体论、吸热论和催化脱水论通常适用于纤维素纤 维织物，而熔滴作用和吸收游离基作用通常适用于合成纤维织物 。11第四节 纤维素纤维织物的阻燃整理v 纤维素的燃烧过程（COMBUSTION OF CELLULOSE）When cellulose fibers are heated, three classes of volatile chemicals are generated at pyrolysis temperature, 350C, oflammable volatiles（可燃性挥发物）, e.g., alcohol
11、s, aldehydes and alkanes, oflammable gases（可燃性气体）, e.g., carbon monoxide, ethylene and methane。 onon-flammable gases （可燃性气体）, e.g., carbon dioxide and water vapor.If oxygen is present when the pyrolysis products reach or exceed the combustion temperature, oxidation takes place (burning) and the vola
12、tiles are converted to carbon dioxide and water as shown in figure 64. 1213 Levoglucosan（左旋葡聚糖）, shown in figure 65. is the major product formed by the pyrolysis of cellulose. It is the cyclic acetal（乙缩醛）created when the alpha-1,4-glucosidic（甙） linkage is split, and a molecule of water is lost betwe
13、en the C(1) and C(6) hydroxyls of the anhydroglucose （葡萄糖 ）unit.14v 常用阻燃剂及其工艺o硼砂/硼酸或磷酸二氢铵混合物非耐久性阻燃剂，价廉、效果好，用于窗帘等不常洗织物。可用浸轧、喷雾、涂刷等方法应用。 Boric acid (H3BO3) /borax (Na2B4O7) are often used as non-durable flame retardants in applications such as cellulose fibers for insulation. Boron functions in the co
14、ndensed phase as a lewis acid and as mentioned earlier, coats the fiber with a glassy polymer to insulate the polymer.o金属氧化物或氯化物常用锑、钛的氧化物或卤化物，处理纤维后经水解生成氢氧化锑或 钛沉积在纤维表面，作为纤维素的脱水剂，纤维燃烧时生成较多的 固体炭，挥发性物质减少，是一种半耐久性阻燃剂（经15次温和洗 涤），可用浸渍法加工，加工织物手感粗硬，强力下降30%左右。15o磷酸及其盐类常用磷酸、磷酸氢二胺、磷酸二氢胺和聚磷酸胺，由于它们与纤 维素反应，使其燃烧时固体炭
15、量，焦油及可燃性气体，有阻燃 作用，为半耐久阻燃剂，因对纤维损伤严重而不常应用。Phosphorus compounds react with the C(6) hydroxyl of the anhydroglucose unit blocking the formation of levoglucosan. This reduces the amount of fuel to the flame. Additionally, phosphorous promotes char formation. The acidity associated with certain phosphorou
16、s analogues and its electrophilic nature lowers the activation energy for dehydrating cellulose. Additionally there is the possibility of crosslinking cellulose chains which further enhances char formation. 16o Tetrakis(hydroxymethyl) phosphonium Chloride (THPC) 四羟甲基氯化磷四羟甲基氯化磷 P（CH2OH）4+Cl-50年代由美国人发明，现代许多阻燃剂由其衍化而来，是一种耐 久性阻燃剂（其中四个活泼的羟甲基能与纤维素上的甲基反应） 。应用方法： THPC/酰胺法 THPC与TMM、尿素、氢氧化钠、柔软剂等混合组成阻燃工作浴 ， 应用P-
