纤维素基介电材料

Cellulose-Based Dielectric Composite

作为电荷的高效存储设备,介电电容器受到学术界和产业界越来越多的关注,其中介电材料是介电电容器的核心。长久以来,双向拉伸聚丙烯和聚对苯二甲酸乙二醇酯等石油基聚合物作为介电材料广泛应用于商用电容器设备。然而,随着服役环境的变化(如工作温度升高等),聚合物材料的介电常数与充放电效率下降,同时介电损耗与电流漏导增加,导致储能密度大幅降低,亟待开发具有高储能密度的新型可持续聚合物介电材料。纤维素是地球上储量最丰富的天然聚合物,具有可持续、价格低廉、可生物降解等特点,是理想的候选生物基材料。近年来,通过将纤维素纳米纤维、氰乙基纤维素、再生纤维素及醋酸纤维素分别与不同填料进行复合,显著提高了介电常数、击穿场强与充放电效率,获得了一系列具有高储能密度的生物基介电材料。本文总结了上述纤维素基介电材料的研究进展,并对该领域面临的挑战与发展前景进行了探讨与展望。

As an electric charge storage device,dielectric capacitor has attracted growing research interest from both academy and industry.The dielectric material is the key component for the capacitor.Fossil based commercial polymers,such as biaxially oriented polypropylene(BOPP)and polyethylene terephthalate(PET),have been widely used as the dielectric materials in the capacitors.However,the change of service condition(e.g.increasing the temperature)will resulted in the low energy storage density of the fossil based polymer dielectric materials because of the reduced dielectric constant and discharge-charge efficiency,and the increased dielectric loss and current leakage.Therefore,novel sustainable polymer dielectric materials with high energy storage density are highly desirable.As the most abundant natural polymer on the earth,cellulose is considered as the candidate for the potential dielectric materials due to the renewable feedstock,low price and biodegradability,etc.Recently,cellulose-based dielectric composites with high energy storage density have been developed,which show improved dielectric constant,breakdown strength and discharge-charge efficiency.This article focuses on the advances in cellulose-based dielectric composites mentioned above.Moreover,the challenges and opportunities are discussed for the further development in the related topics.