The development in the field of electronics and microelectronics has greatly promoted the research on thermally conductive polymer film materials. However, there is a lack of systematic study on both the analyzing technology of thermal conductivity and the testing methods suitable for polymer films. The light/laser flash analysis (LFA) is the most representative method in transient analysis technique. In this paper, the basic principle, testing conditions and application scope of LFA method were systematically introduced. Thermally conductive polyimide films were taken as the representative examples to analyze the key factors on the testing results in detail, including the film thickness, surface quality, pretreatment conditions, instrument parameters, and data analyzing and processing. In addition, the application of LFA method for testing thermal conductivity along different directions of polymer film materials was further discussed. The results show that the thickness accuracy, surface quality, and transparency of the samples will affect the test results, and the pretreatment methods such as gold sputtering or graphite spraying can effectively improve the test accuracy. In addition, the parameter setting and data processing of the testing instrument will affect the shape of temperature-time curve and the fitting results. Thus, it is necessary to reasonably select the appropriate testing conditions according to the characteristics of polymer film samples.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |