增塑剂对EPDM绝热层可挥发逸出物影响研究

Influence of plasticizer on volatile emission from EPDM insulation

研究了低挥发性增塑剂种类、用量和预烘温度对可挥发逸出物含量及逸出速率的影响,并与常用增塑剂石蜡油做比较。结果表明,低挥发性增塑剂的挥发逸出物含量均低于石蜡油,80℃预烘100 h大豆油(SO)逸出物含量最低,较石蜡油降低38.60%;80℃预烘7 h,SO由6份增加至15份,单位质量绝热层中SO的失重量增加178%;预烘温度升高更多可挥发小分子达到可逸出沸点,逸出物含量明显增加。改变增塑剂种类和增塑剂用量时,影响逸出速率的主要因素为可逸出物含量,因此可逸出物含量越高,逸出速率越快;升高预烘温度可逸出物含量增加,扩散系数增大,逸出速率增加最为显著。因此,若要降低逸出物含量且使逸出速率增加,可将增塑剂替换为SO,并适当提高预烘温度。

Compared with common plasticizer paraffin oil,the effects of low-volatile plasticizers types,dosage and pre-baked temperature on the content and emission rate of volatile were investigated.The results show that the volatile of all low-volatile plasticizers are lower than that of paraffin oil.The volatile content of soybean oil(SO)pre-baked at 80℃for 100 h is the lowest,which is 38.60%lower than paraffin oil.Increase the dosage of SO from 6 phr to 15 phr,the weight loss of SO in unit mass insulation pre-baked at 80℃for 7 h increases by 178%.The higher pre-baked temperature,the more volatile small molecules reach their escapable boiling point,resulting in a higher content of escaped substances obviously.The main factors affecting the escape rate is the content of escaped substances,when the type and dosage of plasticizer are changed.The higher volatile content,the higher escape rate,and the escape rate increases most significantly by increasing the pre-baked temperature because of the increase of both the volatile content and the diffusion coefficient.Therefore,in order to reduce the volatile content,the plasticizer should be substitute by SO,and the pre-baked temperature should be increased appropriately.