In this work, kaolinite (K) was firstly converted to one kind of microporus aluminosilicate (4A) by a green andeconomical method, which was thenacted as the precursor to synthesize two other microporus aluminosilicate (3A and 5A) by ions exchange. After modified and loaded with one kind of rare earth ion (La³⁺), the final product (A‐La) was then used as synergist to enhance fire retardant property for polypropylene (PP) with intumescent flame‐retardants (IFR). The properties of PP composites for thermal stability and flame retardant were studied and demonstrated that A‐La, especially 4A‐La, had the most obviously flame‐retardant effect. Meanwhile, the macro/micro‐structure of char residues and real‐time fourier transform infrared spectroscopy (FTIR) after heating also showed that A‐La were helpful to promote the formation of homogenous and compact intumescent char layer. This dense carbon layer can effectively control the convection of combustion gases mixture, and heat transfer between underlying matrix and outside environment.

中文翻译：

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以高岭土为增效剂的改性微孔硅铝酸盐增强聚丙烯耐火性的有效方法

在这项工作中，高岭石（K）首先通过绿色经济的方法转化为一种微孔硅铝酸盐（4A），然后作为前体通过离子交换合成另外两种微孔硅铝酸盐（3A和5A）。改性后负载一种稀土离子（La ³⁺），然后将最终产品（A‐La）用作增效剂，以增强具有膨胀型阻燃剂（IFR）的聚丙烯（PP）的阻燃性。研究了聚丙烯复合材料的热稳定性和阻燃性能，并证明了A‐La，尤其是4A‐La具有最明显的阻燃效果。同时，炭渣的宏观/微观结构以及加热后的实时傅立叶变换红外光谱（FTIR）也显示出A‐La有助于促进均匀且致密的膨胀型炭层的形成。这种致密的碳层可以有效地控制燃烧气体混合物的对流以及底层基质与外部环境之间的热传递。