【摘要】 <正> 聚四氟乙烯(Polytetrafluoroethylene,PTFE)树脂经模压、烧结等加工过程,制成聚四氟乙烯塑料制品。PTFE本身性能稳定,生物活性极低,曾以25％PTFE树脂的饲料喂饲大鼠及兔子三个月,均未见异常反应及病理组织学改变。本品加工过程需经高温(约380℃)烧结,如使用或加工温度超过限度,则可引起聚合体的热解,产生有毒的热解更多还原

【Abstract】 Polytetrafluoroethylene(PTFE)is one of the new type synthetic polymers, which has widespread utilization because of its desirable ohemioo-physioal properties and inert biological activity. Owing to iiss thermal stability, many of the usages and manufacturing processes of PTFE can be carried out at elevated temperature (380℃). Former investigation has shown that PTFE does evolve toxic materials, called pyrolysis products, when heated above certain degrees of temperature. It has been observed that in the proximity to sintering temperature (350℃) of PTFE, pyrolysates evolved would cause adverse effects.In order to seek the basis for establishing the MAO of pyrolysis products of PTFE in the air of working premises, animal experiments had been carried out. Two groups of 7 rabbits were exposed to different concentrations of pyrolysis products, which evolved from the PTFE at the sintering temperature (400±10℃), 3 hours per day for 3 months. Another group of 7 rabbits served as control.The results of the analyses of the air samples taken from exposure chambers indicated that hexafluoropropylene (HFP), tetrafluoroethylene (TFE), oetafluprocyolo-butane (OFOB), hydrogen fluoride (HF), carbonyl fluoride (COF2) and trace of pernuoroisobutylene(PFIB) were the major components in pyrolysis products of PTFE. However, the principal toxic effects were due to HF, COFa and traces of PFIB. All of these three toxicants were strongly irritative to the lungs. The lesions observed in the lungs of exposed animals were hyperplastio after exposure to lower concentration and necrotic after bigher concentration.Based upon the data of animal experiments and field surveys, the values proposed for establishing the MAO of several pyrolysis products of PTFE in the air of working premises are: HFP 1.0-1.2, TFE6-8, OFCB 12-16, PFTB0.05, HF0.1and COF20.3mg/m3.更多还原