模内装饰印刷涂层对薄膜导热系数的影响

Effects of the Coating on the Thermal Conductivity of the Film in the In-mold Decoration

通过实验研究了汽车内饰模内装饰(IMD)工艺用聚碳酸酯(PC)、丙烯腈-丁二烯-苯乙烯共聚物(ABS)、聚对苯二甲酸乙二醇酯(PET)三种材料薄膜的印刷涂层对薄膜的传热性能影响。通过导热系数测试和热重(TG)分析研究了不同温度下涂层对导热系数的影响;通过扫描电子显微镜(SEM)对不同温度处理过的样品进行断面和形貌分析,研究了印刷涂层对薄膜导热系数的影响机理。研究发现,PC、ABS、PET三种材料的有涂层和无涂层的薄膜导热系数都随温度的升高而增大;但当温度高于150℃左右时,有涂层薄膜导热系数急剧增大。当温度低于薄膜软化温度时,有涂层薄膜的导热系数比无涂层薄膜的导热系数小,当温度高于薄膜的软化温度时,有涂层薄膜的导热系数较无涂层薄膜的导热系数高。低于薄膜软化温度时,随着温度的升高,INS用无涂层ABS薄膜与有涂层ABS薄膜的导热系数差值逐渐减小;而IMR用无涂层PET薄膜与有涂层PET薄膜的导热系数差值逐渐增大。

The effects of the coating on the heat transfer performance of in-mold decoration （IMD） films made of PC, ABS and PET materials were studied. The influences of coating on the thermal conductivity at different temperatures were investigated by thermal conductivity test and thermogravimetric analysis （TG）. And the influence mechanism was analyzed by scanning electron microscopy （SEM） of the section and morphology of film samples. The experiment results show that the thermal conductivities of the coated and uncoated polycarbonate （PC）, acrylonitrile-butadiene-styrene copolymer （ABS） and polyethylene terephthalate （PET） films all increase with temperature. But when the temperature is higher than 150 ℃, the heat conductivity coefficients of coated films increase sharply. Compared with the uncoated films, the heat conductivity coefficients of coated films are smaller when the temperature is lower than the film softening temperature, and then they are bigger with the temperature beyond the softening point. The difference of thermal conductivity between the coated and uncoated ABS films used in INS process is gradually reduced, and the difference between coated and uncoated PET films used in IMR process is gradually enlarged, with the elevated temperature lower than softening point.