Amplitude Spectrum Analysis of Dynamic FT-IR Spectra of Uniaxially Drawn Poly(Ethylene Terephthalate) Film with a Variable-Temperature Polymer Stretcher

1997 ◽  
Vol 51 (4) ◽  
pp. 598-600 ◽  
Author(s):  
Masashi Sonoyama ◽  
Kunihiro Shoda ◽  
Gen Katagiri ◽  
Hideyuki Ishida ◽  
Tatsuhiko Nakano ◽  
...  
Keyword(s):  
Ir Spectra ◽  
Ethylene Terephthalate ◽  
Variable Temperature ◽  
Amplitude Spectrum ◽  
Dynamic Variations ◽  
Poly Ethylene Terephthalate ◽  
Dynamic Spectra ◽  
Ft Ir ◽  
Poly Ethylene ◽  
Pet Film

Dynamic FT-IR spectra of uniaxially 5×-drawn poly(ethylene terephthalate) (PET) film at a temperature of 30 to 150 °C were measured with the use of a variable-temperature polymer stretcher, and amplitude spectrum analyses of the dynamic spectra were carried out. A drastic decrease in dynamic variations of the trans C–O stretching band was observed above the glass-to-rubber transition temperature. This observation suggests that the trans C–O bond in the ethylene glycol unit is closely related to changes in macroscopic mechanical properties of PET film in the glass-to-rubber transition.

Amplitude Spectrum Approach in Dynamic FT-IR Spectroscopy of Uniaxially Oriented Poly(Ethylene Terephthalate) Films. Part I: Draw Ratio Dependence

1997 ◽  
Vol 51 (3) ◽  
pp. 346-349 ◽  
Author(s):  
Masashi Sonoyama ◽  
Kunihiro Shoda ◽  
Gen Katagiri ◽  
Hideyuki Ishida
Keyword(s):  
Structural Changes ◽  
Ethylene Terephthalate ◽  
Amplitude Spectrum ◽  
Data Manipulation ◽  
Poly Ethylene Terephthalate ◽  
Ft Ir ◽  
Poly Ethylene ◽  
Mechanical Stretching ◽  
Methylene Group ◽  
Ft Ir Spectroscopy

A method of data manipulation using the dynamic magnitude spectrum and the static absorbance spectrum is applied to uniaxially drawn poly(ethylene terephthalate) films with five different draw ratios for the evaluation of the amplitude of dynamic structural changes under a sinusoidal strain at the level of a functional group. This analysis revealed that, in the drawn film, the skeletal structures, such as the C–O bond in the ethylene glycol unit and the phenyl ring, are susceptible to deformation by mechanical stretching, while the dynamic structural changes around the methylene group are small. It was assumed that the backbone of the polymer is responsible for the change of the mechanical properties induced by the drawing of the film.

Dynamic Step-Scan Two-Dimensional Fourier Transform Infrared Studies of Uniaxially Drawn Poly(Ethylene Terephthalate) Film

1996 ◽  
Vol 50 (3) ◽  
pp. 377-381 ◽  
Author(s):  
Masashi Sonoyama ◽  
Kunihiro Shoda ◽  
Gen Katagiri ◽  
Hideyuki Ishida
Keyword(s):  
Ethylene Glycol ◽  
Phenyl Ring ◽  
Ethylene Terephthalate ◽  
High Mobility ◽  
Two Dimensional ◽  
Poly Ethylene Terephthalate ◽  
Dynamic Spectra ◽  
Infrared Studies ◽  
Poly Ethylene ◽  
Mechanical Stretching

Dynamic infrared spectra of uniaxially drawn poly(ethylene terephthalate) (PET) under a sinusoidal strain were examined. A very intense dynamic band at 973 cm−1 assigned to the trans C-O stretching mode indicated stress-induced high mobility around the C-O bond in the ethylene glycol units. It was supposed that derivative-like skeletal bands observed in the dynamic spectra originated from the stress-induced frequency shift. Two-dimensional correlation analyses of the dynamic spectra were also carried out and revealed that the phenyl ring 18a band at 1018 cm−1 and the phenyl ring 19b band at 1410 cm−1 were composed of three and two independent components, respectively. The correlation peaks between the phenyl ring and CH2 vibrational modes showed that orientation of the methylene group in the ethylene glycol unit, induced by mechanical stretching, is faster than that of the phenyl ring in the terephthalate unit.

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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