IMDEA Materials Institute, C/Eric Kandel 2, 28906 Getafe, Madrid, Spain.
IMDEA Materials Institute, C/Eric Kandel 2, 28906 Getafe, Madrid, Spain.
J Hazard Mater. 2017 Oct 5;339:143-153. doi: 10.1016/j.jhazmat.2017.05.047. Epub 2017 Jun 15.
As a naturally abundant biopolymer, chitosan is considered to be a suitable adsorbent for stannate (SnO) in tin plating wastewater. However, mass transfer of the adsorbent and its recycling remain challenging problems. Though flexible poly(vinyl chloride) (PVC) is highly flammable due to the addition of plasticizers, the traditional flame retardant, antimony trioxide (SbO), is potentially harmful. In this study, chitosan was anchored onto the surface of PVC resin to adsorb SnO from wastewater. Thereafter, tin-doped chitosan-coated PVC resin was readily recycled and processed into a flexible PVC composite (modified fPVC). The limiting oxygen index value of the modified fPVC increased to 33.1%, and the peak heat release rate decreased to 161kW/m. In addition to reducing fire hazards, this approach also decreased the content of harmful hydrogen chloride gas released during the combustion of modified fPVC. Meanwhile, the tensile properties of modified fPVC were enhanced compared with those of the SbO-treated sample. These results indicated the synthesis of an eco-friendly SbO-free flexible PVC composite that poses a low fire hazard.
壳聚糖作为一种天然存在的生物聚合物，被认为是一种适合用于镀锡废水的锡酸盐（SnO）吸附剂。然而，吸附剂的传质及其回收仍然是具有挑战性的问题。尽管聚氯乙烯（PVC）由于添加了增塑剂而具有很高的可燃性，但传统的阻燃剂三氧化二锑（SbO）可能是有害的。在这项研究中，壳聚糖被固定在 PVC 树脂的表面上，以从废水中吸附 SnO。此后，锡掺杂壳聚糖涂覆的 PVC 树脂很容易被回收，并加工成一种柔性 PVC 复合材料（改性 fPVC）。改性 fPVC 的极限氧指数值增加到 33.1%，峰值热释放率降低到 161kW/m。除了降低火灾风险外，这种方法还减少了在改性 fPVC 燃烧过程中释放的有害氯化氢气体的含量。同时，与 SbO 处理的样品相比，改性 fPVC 的拉伸性能得到了提高。这些结果表明，合成了一种环保的无 SbO 柔性 PVC 复合材料，其火灾风险较低。
