Ionomeric Blends of Poly(ethyl acrylate-co-4-vinylpyridine) with Zinc-Neutralized Sulfonated Poly(ethylene terephthalate). 1. Effect of Specific Interactions upon the Amorphous Phase

1994 ◽  
Vol 27 (11) ◽  
pp. 3027-3032 ◽  
Author(s):  
Chui-Wah A. Ng ◽  
Martin J. Lindway ◽  
William J. MacKnight
Keyword(s):  
Amorphous Phase ◽  
Ethylene Terephthalate ◽  
Ethyl Acrylate ◽  
Specific Interactions ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
Sulfonated Poly

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.

Preparation and hydrolytic degradation of sulfonated poly(ethylene terephthalate) copolymers

Polymer ◽  
2003 ◽  
Vol 44 (24) ◽  
pp. 7281-7289 ◽  
Author(s):  
Oscar Gaona ◽  
Darwin P.R. Kint ◽  
Antxon Martı́nez de Ilarduya ◽  
Abdelilah Alla ◽  
Jordi Bou ◽  
...  
Keyword(s):  
Ethylene Terephthalate ◽  
Hydrolytic Degradation ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
Sulfonated Poly
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