Amorphous phase evolution during crystallization of poly(ethylene-terephthalate)

1992 ◽  
Vol 270 (12) ◽  
pp. 1182-1187 ◽  
Author(s):  
G. Vigier ◽  
J. Tatibouet ◽  
A. Benatmane ◽  
R. Vassoille
Keyword(s):  
Amorphous Phase ◽  
Ethylene Terephthalate ◽  
Phase Evolution ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

Constant-Temperature Embossing of Amorphous Poly(Ethylene Terephthalate) Films

2007 ◽  
Author(s):  
Donggang Yao ◽  
Pratapkumar Nagarajan ◽  
K. R. T. Ramasubramani
Keyword(s):  
Thermal Cycling ◽  
Amorphous Phase ◽  
Constant Temperature ◽  
Ethylene Terephthalate ◽  
Mold Temperature ◽  
Cycle Times ◽  
Poly Ethylene Terephthalate ◽  
Micro Features ◽  
Poly Ethylene ◽  
Pet Film

In the standard hot embossing process for thermoplastic polymers, thermal cycling is needed in order to soften and subsequently cool and solidify the polymer. This thermal cycling, however, not only results in long cycle times but also deteriorates the quality of embossed features. A new embossing method based on slowly crystallizing polymers was investigated to eliminate thermal cycling. Poly(ethylene terephthalate) was used as a model system for demonstration. Due to its slow crystallization, amorphous PET film can be made by casting a PET melt onto a chill roll. The amorphous PET film was embossed at a constant temperature of 180°C for a period of time comparable to or longer than PET’s half-time of crystallization. During constant-temperature embossing, the film first liquefies, caused by rubber softening of the amorphous phase, and then solidifies, resulting from the crystallization of the amorphous phase. Since the embossed film is hardened under the constant mold temperature, no cooling is needed. Selected micro features, including circular microchannels and high aspect ratio rectangular microchannels, were successfully embossed using a total cycle time about 40 s.

Structure of the amorphous phase in crystallizable polymers: poly(ethylene terephthalate)

1991 ◽  
Vol 24 (5) ◽  
pp. 1185-1189 ◽  
Author(s):  
N. S. Murthy ◽  
S. T. Correale ◽  
H. Minor
Keyword(s):  
Amorphous Phase ◽  
Ethylene Terephthalate ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

Study of the Amorphous Phase in Semicrystalline Poly(ethylene terephthalate) via Physical Aging

2002 ◽  
Vol 35 (8) ◽  
pp. 3097-3103 ◽  
Author(s):  
Jun Zhao ◽  
Jijun Wang ◽  
Chaoxu Li ◽  
Qingrong Fan
Keyword(s):  
Amorphous Phase ◽  
Ethylene Terephthalate ◽  
Physical Aging ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

Influence of orientation in the amorphous phase of poly(ethylene terephthalate)

1991 ◽  
Vol 192 ◽  
pp. 155-163 ◽  
Author(s):  
A. Bernes ◽  
D. Chatain ◽  
C. Lacabanne ◽  
G. Lorentz
Keyword(s):  
Amorphous Phase ◽  
Ethylene Terephthalate ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

scholarly journals The role of the amorphous phase in the re-crystallization process of cold-crystallized poly(ethylene terephthalate)

2008 ◽  
Vol 27 (4) ◽  
pp. 365-373 ◽  
Author(s):  
M. Pieruccini ◽  
A. Flores ◽  
U. Nöchel ◽  
G. Di Marco ◽  
N. Stribeck ◽  
...  
Keyword(s):  
Amorphous Phase ◽  
Ethylene Terephthalate ◽  
Crystallization Process ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

Dependence of Mechanical Properties on Crystalline, Intermediate, and Amorphous Phases in Poly(Ethylene Terephthalate) Fibers

1977 ◽  
Vol 47 (4) ◽  
pp. 267-271 ◽  
Author(s):  
B. L. Deopura ◽  
T. B. Sinha ◽  
D. S. Varma
Keyword(s):  
Mechanical Properties ◽  
Amorphous Phase ◽  
Ethylene Terephthalate ◽  
Intermediate Phase ◽  
Loss Modulus ◽  
Phase Index ◽  
Poly Ethylene Terephthalate ◽  
Initial Modulus ◽  
Static Mechanical ◽  
Poly Ethylene

Crystalline, intermediate, and amorphous phase indices have been obtained for poly (ethylene terephthalate) fibers of different draw ratios. Azimuthal x-ray diffraction from the (010) plane is used for such an analysis. The intermediate phase is found to be linearly dependent on the draw ratio of the fibers. Experiments like shrinkage, dynamic, and static mechanical properties have been carried out for these samples, and an attempt is made to relate these properties with different phase indices. Storage modulus, loss modulus, initial modulus, strength, and shrinkage are linearly dependent on the intermediate phase. The elongation is found to be essentially determined by the amorphous phase index. The results provide further evidence for the existence of three phases in drawn PET fibers.

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