石墨模塑聚苯乙烯和普通聚苯乙烯受热行为比较

Comparison of Heating Behavior of Expandable Styrene Polymers Containing Graphite and Normal Expandable Styrene Polymers

利用热失重分析仪和影像式烧结点试验仪对石墨聚苯乙烯泡沫塑料(GEPS)及原料在受热过程中质量随温度变化规律和热裂解变形过程进行了分析,并与普通聚苯乙烯泡沫塑料进行了比较研究。结果表明:GEPS和EPS热失重行为均有2个明显失重阶段,失重主要发生在第二阶段,其中GEPS的热分解温度(θi2)382.7℃较之EPS的236.0℃高出146.7℃;GEPS的最大失重速率温度(θmax2)415.2℃较之EPS的263.7℃高出151.5℃。烧结影像表明:GEPS初始变形温度为128℃,260℃以上时试样熔融流动,GEPS相对于EPS在较高温度下出现熔滴现象。

The mass loss and pyrolytic deformation of graphite-embedded polystyrene （GEPS） and normal expandable polystyrene （EPS） foams were investigated by thermogravity analyzer and stereo pyroscope. As seen from the thermogravity curves,both EPS and GEPS foams presented two obvious stages of mass loss,and the high-temperature stage gave the main contribution of the tota! mass loss. Besides,it was found that the pyrolytic point Oi2 of GEPS reached to 382 ℃, significantly higher than that of EPS （236.0 ℃ ）. Meanwhile, the maximan pyrolytic rate 0max2 reached to 415.2 ℃ , also obviously exceeded over that of EPS（263.7 ~C ）. The pyroscope observation revealed that GEPS foams showed off the deformation at 128 ℃ while began to melt with fluxibily at 260 ℃ ,much higher over EPS foams.