Investigation of bond strength and failure mode between SiC-coated mesophase ribbon fiber and an epoxy matrix
9
Citation
16
Reference
10
Related Paper
Citation Trend
Keywords:
Thermosetting polymer
Ribbon
Polyethylene naphthalate
The chemical and physical processes involved in formation of mesophase pitch are described. Carbonaceous mesophase exhibits properties of both nematic liquid crystals and glass-like pitches. Mesophase development requires polymerization of aromatic pitch components to a sufficient molecular size, and a proper concentration balance between molecules with different mesophase forming tendencies.
Cite
Citations (19)
Carbon fibers
Cite
Citations (22)
Ribbon
Cite
Citations (45)
The effect of ferrocene in pitch on nucleation and growth processes of mesophase was investigated from the behavior of iron. The quinoline soluble coal-tar pitch to which ferrocene was added, was heat-treated at 430°C for a certain period. Quinoline insoluble part in the heat-treated pitch was separated by solvent extraction with quinoline. Then, the quinoline insoluble part was treated with HCl. Iron contents in the heat-treated pitch, the quinoline insoluble part, and the quinoline insoluble part treated with HCl were examined. The obtained results are as follows.Ferrocene added in pitch was already decomposed at 430°C and changed into the fine crystals of α-Fe and FeS, which covered the surface of mesophase spherules formed in pitch. The mesophase spherules were found to have almost the same size. Amounts of mesophase formation in the ferrocene-added pitch were larger than those in the pitch having no ferrocene content. From these results, it is considered that the iron crystals controll the size of mesophase spherules and accelerate the mesophase formation. Furthermore, when the mesophase coalesces each other, the crystals not only covers the surface of the coalesced mesophase but also exists inside the mesophase.It is also made clear that the shape of mesophase spherules changes from lemon-like form to spherical form with growth of mesophase spherules.
Quinoline
Cite
Citations (4)
A new 13C-NMR measurement technique, named fused-state 13C-NMR, has been developed. Using this technique, many aspects of carbonaceous mesophase have been elucidated: Constituents of soft mesophase have methyl and/or naphthenic groups whereas those of hard mesophase have no aliphatic groups. The order parameter of carbonaceous mesophase in the nematic phase is about 0.7. Very small molecules such as hexamethylbenzene and pyrene orientate in a carbonaceous mesophase. In a liquid crystalline phase, all oriented molecules in a carbonaceous mesophase (including the small molecules trapped in the mesophase) fluctuate around the orientation axis in the same manner. That is, an oriented molecule behaves as if it were trapped between two walls the distance between which is about 1.0 nm. The analyzed results rule out the assertion that soft mesophase is a gel and also rule out the existence of basic structural units. A constructed model for molecular ordering in a mesophase has clarified some pending questions on carbonaceous mesophase.
Hexamethylbenzene
Cite
Citations (0)
A method in determination of the mesophase contents of pitches are presented. The method is based on the reflectivity difference between a mesophase part and an isotropic part. In order to get clear contrast between a mesophase part and an isotropic part, image processing is used. The method achieved accurate determination of the mesophase content from 0% to 100% in several minuets.
Cite
Citations (0)
Polyethylene naphthalate
Synthetic fiber
Cite
Citations (3)
Mesophase pitch is the pioneer body of the new carbon materials.This paper reveals recent research aspects of mesophase pitch such as transform mechanism,the composition,properties,and the influencing factors of mesophase pitch and the latest application of mesophase pitch.
Carbon fibers
Cite
Citations (0)
Coalescence (physics)
Reactivity
Cite
Citations (0)
Films of poly(ethylene naphthalate) (PEN) and poly(ethylene naphthalate bibenzoate) (PENBB) have been drawn under a variety of conditions of temperature and strain rate to determine the conditions under which a nematic-like mesophase structure can be produced. In PEN the combination of low temperature and high-strain rate encourages mesophase formation, while in PENBB the mesophase was formed under all conditions where it proved possible to draw the material at all. A molecular modelling study of the mesophase in PEN and in poly(ethylene terephthalate) (PET) offers possible structures for the mesophase and showed that the mesophase structure could be stable once formed © 1997 John Wiley & Sons, Ltd.
Poly ethylene
Polyethylene naphthalate
Cite
Citations (0)