Ciolacu Florin, Măluțan Teodor, Lisa Gabriela, Ichim Mariana
"Cristofor Simionescu" Faculty of Chemical Engineering and Environmental Protection, "Gheorghe Asachi" Technical University of Iasi, 73 Prof. Dr. Doc. D. Mangeron Blvd, 700050 Iasi, Romania.
Faculty of Industrial Design and Business Management, "Gheorghe Asachi" Technical University of Iasi, 29 Prof. Dr. Doc. D. Mangeron Blvd, 700050 Iasi, Romania.
Polymers (Basel). 2024 Dec 8;16(23):3442. doi: 10.3390/polym16233442.
Increasing environmental awareness has boosted interest in sustainable alternatives for binding natural reinforcing fibers in composites. Utilizing lignin, a biorenewable polymer byproduct from several industries, as a component in polymer matrices can lead to the development of more eco-friendly and high-performance composite materials. This research work aimed to investigate the effect of two types of lignin (lignosulfonate and soda lignin) on the properties of hemp fiber-reinforced polypropylene composites for furniture applications. The composites were produced by thermoforming six overlapping layers of nonwoven material. A 20% addition of soda lignin or lignosulfonate (relative to the nonwoven mass) was incorporated between the nonwoven layers made of 80% hemp and 20% polypropylene (PP). The addition of both types of lignin resulted in an increase in the tensile and bending strength of lignin-based composites, as well as a decrease in the absorbed water percentage. Compared to oriented strand board (OSB), lignin-based composites exhibited better properties. Regarding the two types of lignin used, the addition of lignosulfonate resulted in better composite properties than those containing soda lignin. Thermal analysis revealed that the thermal degradation of soda lignin begins long before the melting temperature of polypropylene. This early degradation explains the inferior properties of the composites containing soda lignin compared to those with lignosulfonate.
环境意识的提高激发了人们对复合材料中天然增强纤维可持续替代粘结剂的兴趣。利用木质素（一种来自多个行业的生物可再生聚合物副产品）作为聚合物基体的一种成分，可以开发出更环保、高性能的复合材料。本研究旨在研究两种类型的木质素（木质素磺酸盐和碱木质素）对用于家具的麻纤维增强聚丙烯复合材料性能的影响。这些复合材料是通过热成型六层重叠的非织造材料制成的。在由80%的麻和20%的聚丙烯（PP）制成的非织造层之间加入20%（相对于非织造材料质量）的碱木质素或木质素磺酸盐。两种类型木质素的加入均导致木质素基复合材料的拉伸强度和弯曲强度增加，以及吸水率降低。与定向刨花板（OSB）相比，木质素基复合材料表现出更好的性能。关于所使用的两种类型的木质素，木质素磺酸盐的加入导致复合材料性能优于含碱木质素的复合材料。热分析表明，碱木质素的热降解在聚丙烯的熔融温度之前很久就开始了。这种早期降解解释了含碱木质素的复合材料与含木质素磺酸盐的复合材料相比性能较差的原因。
