Natural fillers composed of cellulose, lignin and fillers with a varying lignin/cellulose ratio (flax, jute, curauà fibers and miscanthus stem fragments) were used to prepare composites with polypropylene using the same procedure, with or without a maleic anhydride–grafted polypropylene (MA-g-PP) coupling agent. A clear acceleration of the crystallization kinetics was observed in the presence of miscanthus stem fragments. For non-coupled composites, the size and aspect ratio of fragments had no significant influence onto the crystallization kinetics of polypropylene. The presence of the MA-g-PP coupling agent increased even more the kinetics. A clear effect of the nature of the polymers present in the filler was observed. There is a direct relationship between the values of the Avrami kinetic constant k for the six fillers and their lignin content, the more effective to enhance crystallization kinetics being pure cellulose. Lignin has no effect onto the crystallization kinetics of polypropylene.

天然填料由纤维素，木质素和木质素/纤维素比变化的填料（亚麻，黄麻，咖喱粉纤维和猕猴桃茎碎片）组成，使用相同的步骤，用或不用马来酸酐接枝聚丙烯，用聚丙烯制备复合材料（ MA- g -PP）偶联剂。在存在桔梗茎碎片的情况下，观察到结晶动力学的明显加速。对于非偶联复合材料，碎片的大小和长宽比对聚丙烯的结晶动力学没有显着影响。MA-g-PP偶联剂的存在甚至增加了动力学。观察到存在于填料中的聚合物的性质的明显效果。Avrami动力学常数之间存在直接关系对于六个填料及其木质素含量的k，更有效地增强结晶动力学的是纯纤维素。木质素对聚丙烯的结晶动力学没有影响。