A refined equation of state of polymer crystals

1980 ◽  
Vol 18 (3) ◽  
pp. 393-406 ◽  
Author(s):  
V. S. Nanda ◽  
O. P. Pahuja ◽  
F. C. Auluck
1982 ◽  
Vol 109 (1) ◽  
pp. 183-188 ◽  
Author(s):  
S. C. Goel ◽  
V. S. Nanda

1988 ◽  
Vol 6 (3-4) ◽  
pp. 157-199 ◽  
Author(s):  
Robert E. Setchell ◽  
Paul A. Taylor

Author(s):  
J. P. Colson ◽  
D. H. Reneker

Polyoxymethylene (POM) crystals grow inside trioxane crystals which have been irradiated and heated to a temperature slightly below their melting point. Figure 1 shows a low magnification electron micrograph of a group of such POM crystals. Detailed examination at higher magnification showed that three distinct types of POM crystals grew in a typical sample. The three types of POM crystals were distinguished by the direction that the polymer chain axis in each crystal made with respect to the threefold axis of the trioxane crystal. These polyoxymethylene crystals were described previously.At low magnifications the three types of polymer crystals appeared as slender rods. One type had a hexagonal cross section and the other two types had rectangular cross sections, that is, they were ribbonlike.


Author(s):  
Philippe Pradère ◽  
Edwin L. Thomas

High Resolution Electron Microscopy (HREM) is a very powerful technique for the study of crystal defects at the molecular level. Unfortunately polymer crystals are beam sensitive and are destroyed almost instantly under the typical HREM imaging conditions used for inorganic materials. Recent developments of low dose imaging at low magnification have nevertheless permitted the attainment of lattice images of very radiation sensitive polymers such as poly-4-methylpentene-1 and enabled molecular level studies of crystal defects in somewhat more resistant ones such as polyparaxylylene (PPX) [2].With low dose conditions the images obtained are very noisy. Noise arises from the support film, photographic emulsion granularity and in particular, the statistical distribution of electrons at the typical doses of only few electrons per unit resolution area. Figure 1 shows the shapes of electron distribution, according to the Poisson formula :


1998 ◽  
Vol 94 (5) ◽  
pp. 809-814 ◽  
Author(s):  
C. BARRIO ◽  
J.R. SOLANA

2000 ◽  
Vol 10 (PR5) ◽  
pp. Pr5-281-Pr5-286
Author(s):  
M. Ross ◽  
L. H. Yang ◽  
G. Galli

1980 ◽  
Vol 41 (C2) ◽  
pp. C2-83-C2-83
Author(s):  
Ph. Choquard
Keyword(s):  

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