Brenner Markus, Weichold Oliver
Institute of Building Materials Research, Schinkelstraße 3, 52072 Aachen, Germany.
Polymers (Basel). 2021 Nov 12;13(22):3908. doi: 10.3390/polym13223908.
Most rubbers used today rely on sulphur as a cross-linking agent and carbon black from fossil resources to modify the mechanical properties. A very promising substitute can be found in natural keratins such as feathers. These are not only tough, but also contain a relevant amount of sulphur in the form of disulphide bridges. The present study shows that these can be activated under vulcanisation conditions and then bind covalently to EPDM rubber to form a cross-linked network. Feathers were cut into lengths of 0.08, 0.2, and 1 mm and incorporated at 38, 69, or 100 phr into EPDM mixtures containing either no carbon black or no carbon black nor sulphur. The presence of feather cuttings increases the tensile and compressive strength as well as the hardness, and reduces the rebound resilience. Due to their high (approximately 17%) nitrogen content, the feathers also improve the thermal stability of the composite, as the main degradation step is shifted from 400 °C to 470 °C and the decomposition is significantly slowed down. Since elastomers are a large market and feathers in particular are a high-volume waste, the combination of these two offers enormous ecological and economic prospects.
如今使用的大多数橡胶依赖硫磺作为交联剂，并使用来自化石资源的炭黑来改善机械性能。一种非常有前景的替代品是天然角蛋白，如羽毛。这些角蛋白不仅坚韧，还以二硫键的形式含有相当数量的硫。本研究表明，这些二硫键在硫化条件下可以被激活，然后与三元乙丙橡胶（EPDM）共价结合形成交联网络。将羽毛切成0.08、0.2和1毫米的长度，并以38、69或100份每百份橡胶（phr）的比例加入不含炭黑或既不含炭黑也不含硫磺的EPDM混合物中。羽毛碎片的存在提高了拉伸强度、抗压强度以及硬度，并降低了回弹性。由于羽毛含有高（约17%）氮含量，它们还提高了复合材料的热稳定性，因为主要降解步骤从400℃转移到470℃，并且分解明显减缓。由于弹性体是一个大市场，特别是羽毛是大量的废弃物，这两者的结合具有巨大的生态和经济前景。
