Maqsood Muhammad, Seide Gunnar
Aachen Maastricht Institute for Biobased Materials, Faculty of Science and Engineering, Maastricht University, Urmonderbaan 22, 6167 RD Geleen, The Netherlands.
Materials (Basel). 2019 Sep 23;12(19):3095. doi: 10.3390/ma12193095.
The objective of this study is to examine the effect of intumescent flame-retardants (IFR's) on the spinnability of sheath/core bicomponent melt-spun fibers, produced from Polylactic acid (PLA) single polymer composites, as IFR's have not been tested in bicomponent fibers so far. Highly crystalline PLA-containing IFR's was used in the core component, while an amorphous PLA was tested in the sheath component of melt-spun bicomponent fibers. Ammonium polyphosphate and lignin powder were used as acid, and carbon source, respectively, together with PES as a plasticizing agent in the core component of bicomponent fibers. Multifilament fibers, with sheath/core configurations, were produced on a pilot-scale melt spinning machine, and the changes in fibers mechanical properties and crystallinity were recorded in response to varying process parameters. The crystallinity of the bicomponent fibers was studied by differential scanning calorimetry and thermal stabilities were analyzed by thermogravimetric analysis. Thermally bonded, non-woven fabric samples, from as prepared bicomponent fibers, were produced and their fire properties, such as limiting oxygen index and cone calorimetry values were measured. However, the ignitability of fabric samples was tested by a single-flame source test. Cone calorimetry showed a 46% decline in the heat release rate of nonwovens, produced from FR PLA bicomponent fibers, compared to pure PLA nonwovens. This indicated the development of an intumescent char by leaving a residual mass of 34% relative to the initial mass of the sample. It was found that the IFRs can be melt spun into bicomponent fibers by sheath/core configuration, and the enhanced functionality in the fibers can be achieved with suitable mechanical properties.
本研究的目的是研究膨胀型阻燃剂（IFR）对由聚乳酸（PLA）单聚合物复合材料制成的皮芯双组分熔纺纤维可纺性的影响，因为迄今为止IFR尚未在双组分纤维中进行测试。含高度结晶PLA的IFR用于芯组分，而无定形PLA在熔纺双组分纤维的皮层组分中进行测试。聚磷酸铵和木质素粉末分别用作酸和碳源，与作为增塑剂的PES一起用于双组分纤维的芯组分中。在中试规模的熔纺机上生产具有皮芯结构的复丝纤维，并记录纤维机械性能和结晶度随工艺参数变化的情况。通过差示扫描量热法研究双组分纤维的结晶度，并通过热重分析分析热稳定性。由制备好的双组分纤维生产热粘合无纺布样品，并测量其燃烧性能，如极限氧指数和锥形量热法值。然而，织物样品的可燃性通过单火焰源试验进行测试。锥形量热法显示，与纯PLA无纺布相比，由FR PLA双组分纤维制成的无纺布的热释放速率下降了46%。这表明通过留下相对于样品初始质量34%的残余质量形成了膨胀型炭。研究发现，IFR可以通过皮芯结构熔纺成双组分纤维，并且通过合适的机械性能可以实现纤维中增强的功能。
