气相色谱-质谱联用测定酚醛塑料在不同温度下脱出气体的实验研究

Investigation of volatile organic compounds outgassed from bakelite at different temperatures using gas chromatography-mass spectrometry

以有机硅改性酚醛塑料作为实验样品,将其密封于Tedlar气体采样袋中,应用气相色谱-质谱联用仪对该非金属材料在不同温度条件下30 d内脱出的有机物进行定性定量分析。研究了主要脱出有机物———甲苯随时间的变化规律,结果表明:在不同温度下,材料中脱出的甲苯质量占总挥发性有机物的50%以上,材料在40℃和50℃的条件下均有18种有机物脱出,在65℃时,有机物二氟二甲基硅烷从材料样品中释放出来,材料的原有物理性能被破坏;材料在40℃时30 d的甲苯脱气量相当于50℃时5 d的甲苯脱气量,因此,在50℃这个稍高于常温的条件下对材料进行快速脱气处理,不仅有利于加快酚醛塑料中挥发性组分的释放,而且能满足在较短时间对材料释放气体的浓度、毒性进行检测评价的实验要求。

A type of nonmetallic material has been employed to investigate and control contamination levels.Bakelite was sealed in a Tedlar gas sampling bag,and outgassed for 30 days at three different temperatures.Qualitative and quantitative analyses of the volatile organic compounds outgassed from the bakelite were carried out by gas chromatography-mass spectrometry.The major volatile organic compounds outgassed from bakelite-toluene were studied.Toluene constituted 50% or more of the total concentration.Curve fitting and regression were used in data analysis and any toluene outgassing regularities were obtained.18 kinds of volatile organic compounds were detected at both 40 ℃ and 50 ℃.The physical properties of the original material were destroyed at 65 ℃.The amount of toluene outgassed from the bakelite at 40 ℃ for 30 days was equivalent to that obtained by outgassing for 5 days at 50 ℃.There is an equivalent principle for toluene outgassing.The results meet the requirements for evaluation of the toxicity of a material in a short time.