This experimental study is conducted to investigate the effects of boric acid additive into polypropylene in terms of microstructure formation and thermal properties. Boric acid granules are added into pure polypropylene at three mass rates of 0.5, 1.5, and 2.5% which are notated as PP/BA-0.5, PP/BA-1.5, and PP/BA-2.5, respectively. The pure polypropylene material (pure PP) and boric acid reinforced polypropylene composite materials (PP/BA) are manufactured in an injection molding machine. The microstructure of composite materials is examined with an SEM (scanning electron microscope) device. Thermal analyses are conducted by using a TGA (thermogravimetric analyzer) device. In addition, thermal conductivities of composite materials are measured between 10 and 50 °C temperatures. SEM images show that boric acid at 0.5% additive rate forms a homogeneous composite by uniformly spreading the polymer chains, while boric acid at high additive rates of 1.5% and 2.5% becomes agglomerated within the polymer. TGA analyses show that the initial evaluation degradation temperature (T_i) tends to decrease with the addition of boric acid. Thermal conductivity for all examined materials almost linearly increases with temperature at a slope of about 0.0004 [(W m⁻¹ K⁻¹)/K]. Thermal conductivity is reversely proportional to the boric acid additive rate. The thermal conductivity for 2.5% boric acid added polypropylene is about 5% less than pure polypropylene.

本实验研究旨在研究硼酸添加剂对聚丙烯的微观结构形成和热性能的影响。硼酸颗粒以 0.5%、1.5% 和 2.5% 三种质量比率添加到纯聚丙烯中，分别表示为 PP/BA-0.5、PP/BA-1.5 和 PP/BA-2.5。纯聚丙烯材料（pure PP）和硼酸增强聚丙烯复合材料（PP/BA）在注塑机上制造。复合材料的微观结构使用 SEM（扫描电子显微镜）设备进行检查。热分析是通过使用 TGA（热重分析仪）设备进行的。此外，复合材料的热导率是在 10 到 50 °C 的温度下测量的。SEM 图像显示硼酸在 0. 5% 的添加率通过均匀分布聚合物链形成均匀的复合材料，而 1.5% 和 2.5% 的高添加率的硼酸在聚合物内聚集。TGA 分析表明，初始评价降解温度（T_i ) 随着硼酸的加入而降低。所有检查材料的热导率几乎以约 0.0004 [(W m ^-1  K ^-1 )/K]的斜率随温度线性增加。热导率与硼酸添加率成反比。添加 2.5% 硼酸的聚丙烯的热导率比纯聚丙烯低约 5%。