𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Modification of PAN precursor—Its influence on the reaction kinetics

✍ Scribed by R.B. Mathur; O.P. Bahl; V.K. Matta; K.C. Nagpal

Publisher
Elsevier Science
Year
1988
Tongue
English
Weight
609 KB
Volume
26
Category
Article
ISSN
0008-6223

No coin nor oath required. For personal study only.

✦ Synopsis

Polyacrylonitrile (PAN) fibers of special grade variety for making carbon fibers, have been modified by stretching in the presence of a plastisizer to 70% maximum strain. By doing so, the diameter of the original fibers is reduced from 12.5 p. to 10 CL, and the angle of orientation of the molecular chains along the fiber axis is reduced to almost half of its original value as determined by the X-ray flat-plate technique.

The tensile strength and the Young's modulus values of the modified samples show an improvement of about 70% and lOO%, respectively.

A systematic study on the reaction kinetics up to 265°C by following DSC, TGA, and TMA has revealed various interesting deviations in the characteristics of modified PAN precursors over those of the original sample. The implications of these are discussed.

Key WordsAcrylic fiber modification, mechanical properties, thermal characterization, angle of orientation.

📜 SIMILAR VOLUMES

The influence of oxygen on the chemical
The influence of oxygen on the chemical reactions during stabilization of pan as carbon fiber precursor
✍ E. Fitzer; D.J. Müller 📂 Article 📅 1975 🏛 Elsevier Science 🌐 English ⚖ 654 KB

DTA measurements were used for studies of the kinetics of the cyclization and oxidation of PAN during the thermal treatment in air and nitrogen. The cyclization is a first order reaction with an activation energy of about 30 kcal/mole in nitrogen and about 34 kcal/mole in air. For copolymer PAN (5%

237. The influence of textile prestretch
237. The influence of textile prestretching on the cyclization kinetics of pan-fibres
✍ E. Fitzer; Th. Multer 📂 Article 📅 1982 🏛 Elsevier Science 🌐 English ⚖ 127 KB

## I51 sive wrinkling and corrugation. A disclination model seems to apply to the core of round filaments, the transitions from round to cracked structures imply disclination interactions along the length of the filament. 236. The textile prestretching of PAN-fibres as a controlling parameter for

The influence of cobaltous chloride modi
The influence of cobaltous chloride modification on physical properties and microstructure of modified PAN fiber during carbonization
✍ Tse-Hao Ko; Li-Chuan Huang 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 142 KB 👁 2 views

Modification of polyacrylonitrile (PAN) fibers with cobaltous chloride has increased crystal size, crystallinity, and density, and also improved tensile strength and modulus of the resulting carbon fibers. In this study, the effect of cobaltous chloride modification on the physical properties, micro

Oxidation kinetics and its influence on
Oxidation kinetics and its influence on the near-surface effect of diffusion
✍ D.K Reimann; J.P Stark 📂 Article 📅 1970 🏛 Elsevier Science ⚖ 710 KB

Kinetic equations are derived which describe the effect of thermal fluctuations upon tracer oxides on the surface of diffusion specimens. The rate of metal oxide reduction by such fluctuations is shown to be consistent with observations on the near-surface effect (NSE) of diffusion. In particular, t