蓖麻油基含硅阻燃增塑剂的合成及其在聚氯乙烯中的应用

为提高增塑剂的阻燃性能,以可再生资源蓖麻油合成了一种蓖麻油基含硅阻燃增塑剂(Si-ECO),并将其应用到聚氯乙烯(PVC)中。首先将蓖麻油与三甲基氯硅烷反应得到中间体(Si-CO),再与双氧水、甲酸等进行环氧化得到最终产品。采用傅里叶红外光谱(FT-IR)和核磁共振氢谱(~1H NMR)对分子结构进行表征。将该蓖麻油基含硅增塑剂与PVC以及其他助剂进行共混注塑,得到不同含量Si-ECO的PVC树脂。以动态机械分析(DMA)、热重(TG)以及极限氧指数(LOI)等方法测试共混树脂的热力学性能和阻燃性能;以万能力学试验机表征力学性能。试验结果表明:随着Si-ECO阻燃增塑剂含量的增加,其热稳定性有所提高,同时残炭量也增加到4.72%;通过DMA分析可知,该蓖麻油基增塑剂Si-ECO与PVC具有良好的相容性,且能有效提高树脂的阻燃性能,体系的LOI从25.0增加到30.7,热释放速率(HRR)和总释放热(THR)分别为263.14 k W/m^2和29.5 MJ。以蓖麻油为基础合成具有阻燃功能的增塑剂具有广阔的发展前景。

Synthesis and properties of silicon-containing castor oil based plasticizer and its application in poly( vinyl chloride)

Petreleum-based plasticizers such as o-benzene have been banned in many countries such as European Union, United States, Japan and South Korea,due to their toxicity to human.Therefore, the development of non-toxic and environment-friendly plasticizers has become urgent. Plant oil-based plasticizers have the advantages of low toxicity, environmental benign, biodegradability and recyclability.In addition, the increasing demand for fire-resisted material drives the development of novel plasticizer from biomass resources with flame retardant function. A castor oil based flame-retardant plasticizer (Si-ECO) was synthesized by reacted castor oil with chlorotrimethylsilane followed by epoxidation. The chemical structure of Si-ECO was confirmed by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance( 1HNMR). The castor oil-base plasticizer was mixed at different contents with PVC and other additives to obtain PVC resin. The thermal degradation and fire retardant properties of the Si-ECO/PVC were investigated by thermogravimetry analysis(TGA) and limiting oxygen index (LOI). The results showed that the thermal stability and the LOI value were increased with the increasing loading of Si-ECO and the amount of residual carbon also increased to 4.72%. The compatibility of the Si-ECO with PVC blends was investigated by dynamic mechanical analysis (DMA). Meanwhile, the DMA analysis showed that the resulting resin displayed single T g, indicating a homogeneous structure of the resin. The addition of Si-ECO increased the LOI of the PVC resinfrom 25.0 to 30.7. The heat release rate (HRR) and the peak value of total heat release (THR) were 263.14 kW/m^2 and 29.5 MJ, respectively. With the increasing loading of flame retardant plasticizer Si-ECO, the tensile strength of the resulting resin first increased and then decreased. Modulus of elasticity showed a similar trend, and the elongation at break increased from 217.23% to 326.46%. The above results have demonstrated that a variety of flame retardant plasticizers can be synthesized from castor oil and have potential for industrial applications.