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

Optimizing physical aging in poly(ethylene terephthalate)-glycol (PETG)

2018 ◽  
Vol 502 ◽  
pp. 15-21 ◽  
Author(s):  
Jun Guo ◽  
Rui Xiao ◽  
Chuanshuai Tian ◽  
Minqiang Jiang
Keyword(s):  
Ethylene Terephthalate ◽  
Physical Aging ◽  
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.

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