scholarly journals Kinetics of Depolymerization of Poly(ethylene terephthalate) in a Potassium Hydroxide Solution

2001 ◽  
Vol 40 (2) ◽  
pp. 509-514 ◽  
Author(s):  
Ben-Zu Wan ◽  
Chih-Yu Kao ◽  
Wu-Hsun Cheng
Keyword(s):  
Potassium Hydroxide ◽  
Ethylene Terephthalate ◽  
Potassium Hydroxide Solution ◽  
Hydroxide Solution ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
Kinetics Of

Kinetics and mechanism of cyclization of N-(2-methoxycarbonylphenyl)-N’-methylsulphonamide to 3-methyl-(1H)-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide

1991 ◽  
Vol 56 (8) ◽  
pp. 1701-1710 ◽  
Author(s):  
Jaromír Kaválek ◽  
Vladimír Macháček ◽  
Miloš Sedlák ◽  
Vojeslav Štěrba
Keyword(s):  
Potassium Hydroxide ◽  
Acid Catalysis ◽  
Potassium Hydroxide Solution ◽  
Hydroxide Solution ◽  
General Base ◽  
Rate Limiting Step ◽  
Limiting Step ◽  
Cyclization Kinetics ◽  
Rate Limiting ◽  
Kinetics Of

The cyclization kinetics of N-(2-methylcarbonylphenyl)-N’-methylsulfonamide (IIb) into 3-methyl-(1H)-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide (Ib) has been studied in ethanolamine, morpholine, and butylamine buffers and in potassium hydroxide solution. The cyclization is subject to general base and general acid catalysis. The value of the Bronsted coefficient β is about 0.1, which indicates that splitting off of the proton from negatively charged tetrahedral intermediate represents the rate-limiting and thermodynamically favourable step. In the solutions of potassium hydroxide the cyclization of dianion of the starting ester IIb probably becomes the rate-limiting step.

Ethylene Glycol and Glycerin as the Solvent for Alkaline Treatment of Poly(ethylene Terephthalate) Fabrics

1997 ◽  
Vol 67 (10) ◽  
pp. 760-766 ◽  
Author(s):  
M.-C. Yang ◽  
H.-Y. Tsai
Keyword(s):  
Ethylene Glycol ◽  
Degradation Rate ◽  
Ethylene Terephthalate ◽  
Treatment Time ◽  
Alkaline Treatment ◽  
Aqueous System ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
Kinetics Of ◽  
Scanning Electron

Poly(ethylene terephthalate) fabrics are treated with sodium hydroxide using ethylene glycol or glycerin as the solvent. Compared with conventional aqueous alkaline hydrolysis, the degradation rate in ethylene glycol increases tenfold. The kinetics of the alkaline-ethylene glycol treatment show that the weight loss is linear with respect to time. The moisture regain rate and tensile properties of the treated fabrics are measured; other tests include scanning electron microscopy and dyeing properties. The results show that the properties of the treated fabrics do not depend significantly on the solvent; therefore, using ethylene glycol can greatly shorten the treatment time to achieve results similar to those with the conventional aqueous system.

Kinetics of Mass Transfer in the Melt Polycondensation of Poly(Ethylene Terephthalate)

1985 ◽  
Vol 22 (10) ◽  
pp. 1413-1427 ◽  
Author(s):  
Gerald Rafler ◽  
Gerhard Reinisch ◽  
Eckhard Bonatz ◽  
Heinz Versaumer ◽  
Herbert Gajewski ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Ethylene Terephthalate ◽  
Melt Polycondensation ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
Kinetics Of
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