低蛋白天然橡胶在空气和氮气气氛中的热降解行为

Thermal degradation of low protein natural rubber in air and nitrogen atmosphere

采用热重分析法研究了低蛋白天然橡胶(LPNR)在氮气和空气气氛下的热降解和热氧降解行为,并与天然橡胶(NR)在同样条件下的降解行为进行了比较。结果表明,在氮气气氛下,LPNR和NR的热降解都是1步进行,LPNR的起始降解温度(T0)、最大降解温度(Tp)和反应活化能都比NR高,说明其耐热性比NR好;在空气气氛下,LPNR和NR热氧降解都分2步进行,LPNR的T0、Tp总体比NR低,说明LPNR的耐热氧性能比NR差。

The thermodegradation and thermooxidative degradation of low protein natural rubber （LPNR） was studied by thermogravimetry analysis in nitrogen and air atmosphere. And the results were compared with the thermodegradation of natural rubber （NR） in the same conditions. The results showed that the thermodegradation of LPNR and NR in nitrogen atmosphere were a one-step reaction. The initial temperature of mass loss （ To ） and the peak temperature of mass loss（ Tp ） as well as the reaction activation energy of LPNR were higher than those of NR, these suggested that LPNR had better thermal stability than NR in nitrogen atmosphere. The thermooxidative degradation of LPNR and NR in air were a two-step reaction. To, Tp of LPNR were lower than those of NR, these indicated that LPNR had worse thermooxidative stability than NR in air atmosphere.