期刊
ACS APPLIED MATERIALS & INTERFACES
卷 1, 期 9, 页码 1996-2004出版社
AMER CHEMICAL SOC
DOI: 10.1021/am9003705
关键词
cellulose nanocrystals; nanocrystalline cellulose; cellulose whiskers; surface grafting; electrospinning; fiber reinforcement; nanofibers; nanocomposites; nanoparticles; poly(epsilon-caprolactone)
资金
- National Research Initiative of the USDA Cooperative State Research, Education and Extension Service [2007-35504-18290]
- USDA [2007-38420-17772]
We studied the use of cellulose nanocrystals (CNXs) obtained after acid hydrolysis of ramie cellulose fibers to reinforce poly(epsilon-caprolactone) (PCL) nanofibers. Chemical grafting with low-molecular-weight PCL diol onto the CNXs was carried out in an attempt to improve the Interfacial adhesion with the fiber matrix. Grafting was confirmed via infrared spectroscopy and thermo-gravimetric analyses. The polymer matrix consisted of electrospun nanfibers that were collected as nonwoven webs. The morphology as well as thermal and mechanical properties of filled and unfilled nanofibers were elucidated by scanning electron microscopy, differential scanning calorimetry, and dynamic mechanical analysis, respectively. The addition of CNXs into PCL produced minimal changes in the thermal behavior of the electrospun fibers. However, a significant improvement in the mechanical Properties of the nanofibers after reinforcement with unmodified CNXs was confirmed. Fiber webs from PCL reinforced with 2.5% unmodified CNXs showed ca. 1.5-fold increase in Young's modulus and the ultimate strength compared to PCL webs. Compared to the case of grafted nanocrystals, the unmodified ones imparted better morphological homogeneity to the nanofibrillar structure. The grafted nanocrystals had a negative effect on the morphology of nonwoven webs in which individual nanofibers became annealed during the electrospinning process and, therefore, could not be compared to neat PCL nonwoven webs. A rationalization for the different effects of grafted and unmodified CNXs in reinforcing PCL nanofibers is provided.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据