真菌劣化对大麻和亚麻天然纤维复合材料物理及力学性能的影响

Effect of Fungal Deterioration on Physical and Mechanical Properties of Hemp and Flax Natural Fiber Composites.

作者信息

Crawford Bryn, Pakpour Sepideh, Kazemian Negin, Klironomos John, Stoeffler Karen, Rho Denis, Denault Johanne, Milani Abbas S

机构信息

Composites Research Network-Okanagan Node, School of Engineering, University of British Columbia, Kelowna, BC V1V 1V7, Canada.

Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.

出版信息

Materials (Basel). 2017 Oct 31;10(11):1252. doi: 10.3390/ma10111252.

DOI:10.3390/ma10111252

PMID:29088118

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC5706199/

Abstract

The development and application of bio-sourced composites have been gaining wide attention, yet their deterioration due to the growth of ubiquitous microorganisms during storage/manufacturing/in-service phases is still not fully understood for optimum material selection and design purposes. In this study, samples of non-woven flax fibers, hemp fibers, and mats made of co-mingled randomly-oriented flax or hemp fiber (50%) and polypropylene fiber (50%) were subjected to 28 days of exposure to (i) no water-no fungi, (ii) water only and (iii) water along with the fungus. Biocomposite samples were measured for weight loss over time, to observe the rate of fungal growth and the respiration of cellulose components in the fibers. Tensile testing was conducted to measure mechanical properties of the composite samples under different configurations. Scanning electron microscopy was employed to visualize fungal hyphal growth on the natural fibers, as well as to observe the fracture planes and failure modes of the biocomposite samples. Results showed that fungal growth significantly affects the dry mass as well as the tensile elastic modulus of the tested natural fiber mats and composites, and the effect depends on both the type and the length scale of fibers, as well as the exposure condition and time.

摘要

生物基复合材料的开发与应用已受到广泛关注，然而，在储存/制造/使用阶段，由于普遍存在的微生物生长导致其性能退化，这一点在为实现最佳材料选择和设计目的时仍未得到充分理解。在本研究中，将非织造亚麻纤维、大麻纤维以及由随机取向的亚麻或大麻纤维（50%）与聚丙烯纤维（50%）混合制成的毡片样本，分别暴露于以下三种环境中28天：（i）无水无真菌环境；（ii）仅有水的环境；（iii）有水且有真菌的环境。对生物复合材料样本随时间的重量损失进行测量，以观察真菌生长速率以及纤维中纤维素成分的呼吸情况。进行拉伸测试以测量不同配置下复合材料样本的力学性能。采用扫描电子显微镜观察天然纤维上真菌菌丝的生长情况，以及生物复合材料样本的断裂面和失效模式。结果表明，真菌生长显著影响测试的天然纤维毡片和复合材料的干质量以及拉伸弹性模量，且这种影响取决于纤维的类型和长度尺度，以及暴露条件和时间。