Morphological Studies of Cold Drawn Poly(ethylene terephthalate)

Asano, Tsutomu; Seto, Tsuneo

doi:10.1295/polymj.5.72

Cited by 83 publications

(60 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…4) Large fluctuations are also possible for the dihedral angles 8, and f3, showing a flat distribution with broad maxima centered at 180 ' , -90 " and 90 "C 5) Deviations from the perfectly trans state for 8, and 8, are less tolerated in highly extended chains, as shown by the narrow distribution curves of Fig. 3B.…”

Section: Discussionmentioning

confidence: 90%

Conformational analysis of highly extended poly(ethylene terephthalate) chains by Monte Carlo calculations

Auriemma

Corradini

Guerra

et al. 1995

Macro Theory & Simulations

View full text Add to dashboard Cite

SUMMARY:The conformational disorder compatible with the highly extended chains found in mesomorphic poly(ethy1ene terephthalate) has been studied by Monte Carlo calculations on model oligomers confined inside cylindrical tubes. The distribution of torsional angles for such extended chains is characterized by 0-C-C-0 bonds being always in the trans domain, while the C-0-C-C bonds show an approximately similar probability of being found in trans and gauche states, the probability maxima being centered at 90" and -90" in the latter cases. At variance with the torsional angles of the 0-C-C-0 and the ester bonds, always very close to 180 ' , the distributions for all other torsional angles show flat and broad probability maxima, indicating the possibility of substantial deviations from the average value inside each domain. This is also true for the fictitious 0-C. * .C-0 bonds across the phenylene rings, for which a nearly trans geometry is preferred in extended conformations.

show abstract

Section: Discussionmentioning

confidence: 90%

Conformational analysis of highly extended poly(ethylene terephthalate) chains by Monte Carlo calculations

Auriemma

Corradini

Guerra

et al. 1995

Macro Theory & Simulations

View full text Add to dashboard Cite

show abstract

“…72 It must be remembered that in cold-drawn structures, the crystallites are small and highly defective. Because defects in the lattice reduce the energy for molecular motion, 73 the presence of defects can result in faster crystallization (or at lower temperatures), which would stabilize the structure.…”

Section: Effect Of Setting Conditions and Fiber Structurementioning

confidence: 99%

Heat setting

Gupta¹

2001

J of Applied Polymer Sci

View full text Add to dashboard Cite

As-manufactured polymeric fibers are oriented semi-crystalline structures in which the macromolecules are rarely in their equilibrium state. Further instabilities are imparted when the fibers are converted to yarns and the yarns to fabrics. Heat setting is an important industrial process, since it rids them of their instabilities. This review article first considers aspects that are relevant to the broad area of heat setting, viz., the origin of instability, the durability of set, thermal and dynamic mechanical transitions, thermodynamic basis of setting, shrinkage and shrinkage stress, and characterization of the degree of set. The heat setting of major thermoplastic fibers, viz., polyester, polyamide, polyacrylonitrile, polypropylene, and polyethylene has been described in terms of the conditions of heat setting, the structural and morphological changes that occur on heat setting, and the changes in their physical properties. It is shown that heat setting affects such important properties as stress-strain and recovery behavior, dye-uptake, optical properties, and thermal properties. The structural and morphological changes have been described in terms of changes in crystallinity, crystal size and their size distribution, crystal defects, crystal orientation, the nature of the amorphous phase and its orientation, the coupling of the crystalline and amorphous phases, etc. The structural basis of property changes is then discussed.

show abstract

“…Fig. 16a to g show the improvement of order with increasing annealing temperature [9, [29][30][31]. Some of the relevant features of the X-ray patterns will be discussed later.…”

Section: -To0000-mentioning

confidence: 99%

Structure and properties of polyethyleneterephthalate crystallized by annealing in the highly oriented state

1976

View full text Add to dashboard Cite

The structure of polyethyleneterephthalate bristles drawn about five times in the amorphous state and subsequently crystallized at temperatures between 100 and 260 ~ C has been studied by means of small-angle X-ray scattering. In addition density, heat of fusion and wide-angle scattering behaviour were measured. For comparison, similar experiments were carried out with undrawn samples. The results showed that the degree of crystallinity of PET cannot be calculated from density data on the basis of a simple two-phase model, since the effective densities pc and Pa of the crystalline and amorphous regions depend strongly on crystallization and drawing conditions. With rising crystallization temperature the size of the mosaic blocks building up the crystalline layers and their longitudinal mutual order increase whereas the volume fraction of the crystalline region is only rather slightly effected by the annealing temperature. The difference between the effective density Pc and the "X-ray density" Pc of the crystalline layers is supposed to be caused by lattice vacancies in the boundaries of the mosaic blocks.

show abstract

Morphological Studies of Cold Drawn Poly(ethylene terephthalate)

Cited by 83 publications

References 7 publications

Conformational analysis of highly extended poly(ethylene terephthalate) chains by Monte Carlo calculations

Conformational analysis of highly extended poly(ethylene terephthalate) chains by Monte Carlo calculations

Heat setting

Structure and properties of polyethyleneterephthalate crystallized by annealing in the highly oriented state

Contact Info

Product

Resources

About