可膨胀石墨-改性稻草纤维@PBAT发泡珠粒复合材料的制备与性能

Preparation and properties of expandable graphite-modified straw fiber@PBAT foamed bead composites

摘要:

为了制备具有低填充、高性能的聚己二酸/对苯二甲酸丁二醇酯（PBAT）发泡复合材料，先对稻草纤维（RSF）进行磷酸和三聚氰胺改性得到改性稻草纤维（MPRSF），再将MPRSF与可膨胀石墨（EG）进行球磨制备界面焊料（EG-MPRSF），然后经EG-MPRSF包覆PBAT制备EG-MPRSF@PBAT发泡珠粒，最后采用超临界二氧化碳（scCO2）和微波烧结成型技术制备了可膨胀石墨-改性稻草纤维@PBAT（EG-MPRSF@PBAT）发泡珠粒复合材料。基于FTIR、XPS、SEM、EDS表征和TGA、硬度、回弹性和压缩强度测试、极限氧指数测试、垂直燃烧等级测试和锥形量热仪测试，考察EG-MPRSF的质量分数（EG-MPRSF质量占PBAT发泡珠粒质量的百分数，下同）对制备的EG-MPRSF@PBAT发泡珠粒复合材料力学性能、阻燃性能的影响。结果表明，EG-MPRSF@PBAT发泡珠粒复合材料烧结后能保留PBAT发泡珠粒原有的泡孔结构，其硬度、回弹性和压缩强度均有较大的提升，且具有阻燃性能。当EG-MPRSF质量分数为0.2%时，制备的EG-MPRSF@PBAT发泡珠粒复合材料压缩强度、回弹性和硬度分别较不加入EG-MPRSF制备的PBAT发泡珠粒复合材料提升77.8%、16.7% 和45.2%，产烟速率和产烟总量分别下降14.9%和24.8%，热释放总量降低17.1%。

Abstract:

In order to prepare poly (butylene adipate-co-terephthalate) (PBAT) foamed composites with low filling and high performance, rice straw fiber (RSF) was modified with phosphoric acid and melamine to obtain modified rice straw fiber (MPRSF). Then MPRSF and expandable graphite (EG) were ball-milled to prepare interfacial solder (EG-MPRSF), and EG-MPRSF@PBAT foamed beads were prepared by coating PBAT with EG-MPRSF. Finally, expandable graphite-modified straw fiber@PBAT (EG-MPRSF@PBAT) foamed bead composites were prepared by supercritical carbon dioxide (scCO2) and microwave sintering technology. Based on FTIR, XPS, SEM, EDS characterization and TGA, hardness, resilience and compressive strength test, limiting oxygen index test, vertical combustion grade test and cone calorimeter test, the effects of EG-MPRSF mass fraction (EG-MPRSF mass percentage of PBAT foamed bead mass, the same below) on the mechanical properties and flame retardant properties of the prepared EG-MPRSF@PBAT foamed bead composites were investigated. The results show that the EG-MPRSF@PBAT foamed beads composite can retain the original cell structure of PBAT foamed beads after sintering, and its hardness, resilience and compressive strength are greatly improved, and it has flame retardant properties. When the mass fraction of EG-MPRSF was 0.2%, the compressive strength, resilience and hardness of the prepared EG-MPRSF@PBAT foamed bead composites were 77.8%, 16.7% and 45.2% higher than those of the PBAT foamed bead composites without EG-MPRSF, respectively. The smoke production rate and total smoke production decreased by 14.9% and 24.8%, respectively, and the total heat release decreased by 17.1%.