6. 6. 2 Poly(ethylene Terephthalate)1-2
6. 6. 2 . 1 General
Poly(ethylene terephthalate), or PET, is a thermoplastic polyester plant. Such resins may be labeled as low-viscosity or high-viscosity resins. Low-viscosity PET typically has an intrinsic viscosity of less than zero. 75, whilst high-viscosity PET typically has an intrinsic viscosity of zero. 9 or more. Low-viscosity resins, which are at times referred to as " staple" PET (when used in textile applications), are used in a wide variety of products, such as attire fiber, bottles, and photo taking film. High-viscosity resins, sometimes referred to as " industrial" or perhaps " large denier" PET, are used in tire wire, seat belts, and so on.
PET can be used extensively in the manufacture of synthetic fibers (i. e., polyester fibers), which write the largest segment of the man made fiber industry. Since it is actually a pure and regulated materials meeting FDA food get in touch with requirements, FAMILY PET is also trusted in food packaging, just like beverage bottles and frozen food racks that can be heated in a microwave or conventional oven. FAMILY PET bottles bring a variety of foods and drinks, including alcoholic beverages, salad shower, mouthwash, syrups, peanut rechausser, and pickled food. Containers made of PET are being used pertaining to toiletries, cosmetics, and household and pharmaceutical drug products (e. g., toothpaste pumps). Various other applications of PET include molding resins, X-ray and other photographic films, magnetic tape, electric powered insulation, producing sheets, and food product packaging film.
6th. 6. 2 . 2 Process Description3-15
FAMILY PET resins will be produced commercially from ethylene glycol (EG) and possibly dimethyl terephthalate (DMT) or terephthalic acidity (TPA). DMT and TPA are solids. DMT includes a melting point of 140В°C (284В°F), while TPA distingue (goes directly from the solid phase towards the gaseous phase). Both operations first generate the advanced bis-(2-hydroxyethyl)-terephthalate (BHET) monomer and either methanol (DMT reaction) or water (TPA process). The BHET monomer can then be polymerized below reduced pressure with heat and catalyst to produce PET resins. The main reaction pertaining to the DMT process is:
CH3OOC COOCH3 + HOCH2CH2OHГћHO - (OC COOCH2CH2O)nH & 2nCH3OH DMT EG FAMILY PET
The primary response for the TPA procedure is:
HOOC COOH & HOCH2CH2OH ГћHO - (OC COOCH2CH20)nH & 2nH2O
TPA EG PET
Both procedures can produce low- and high-viscosity PET. Inbuilt viscosity depends upon the excessive polymerizer working conditions of: (1) vacuum level, (2) temperature, (3) residence period, and (4) agitation (mechanical design).
9/91 (Reformatted 1/95) Organic Substance Process Sector 6. 6. 2-1 The DMT process is the older of the two processes. Polymerization grade TPA has been offered only since 1963. The production of methanol in the DMT process creates the need for methanol recovery and purification procedures. In addition , this methanol will produce major VOC emissions. In order to avoid the need to restore and detox the methanol and to get rid of the potential VOC emissions, newer plants usually use the TPA process.
DMT Process -
Both group and ongoing operations are used to produce PET using DMT. There are three basic differences between the set process and continuous method: (1) a column-type reactor replaces the kettle aeroplano for esterification (ester exchange between DMT and ethylene glycol), (2) " no-back-mix" (i. elizabeth., no stirred tank) aeroplano designs are essential in the ongoing operation, and (3) diverse additives and catalysts must ensure appropriate product attributes (e. g., molecular excess weight, molecular excess weight distribution).
Figure 6. 6. 2-1 is known as a schematic representation of the PET/DMT continuous method, and the numbers and letters following make reference to this number. Ethylene glycol is sucked from raw material storage (1) and provided to a mix tank (2), where factors and ingredients are added too. From the blend tank, the mixture is fed, along with DMT, to the esterifiers, also known as ester exchange reactors (3). About 0. six...
References: installment payments on your Standards Of Performance Achievable Stationary Sources; Polypropylene, Polyethylene,
Polystyrene, And Poly(ethylene terephthalate), 55 FR 51039, January 11, 1990.
3. Polymer Industry Position By VOC Emissions Lowering That Would Happen From New Source
Efficiency Standards, Pullman-Kellogg, Houston, TX, August 40, 1979.
5. Karel Verschueren, Handbook Of Environmental Data On Organic and natural Compounds, Truck Nostrand
Reinhold Co., Ny, NY, 1983.
5. Last Trip Report To Tennessee Eastman Company is Polyester Herb, Kingsport, TN, Energy And
Environmental Examination, Inc., Bowmanville, NC, March 2, 1980.
6. Crafted communication by R. Electronic. Lee, Tennessee Eastman Co., Kingsport, TN, to A. Limpiti,
Energy And Environmental Analysis, Inc., Clarington, NC, Nov 7, 1980.
9. Final Trip To DuPont 's Poly(ethylene terephthalate) Herb, Kinston, NC, Pacific Environmental
Services, Inc., Durham, NC, February 21 years old, 1989.
Services, Inc., Durham, NC, September 29, 1982.
12. Written communication by D. Sixth is v. Perry, Dietary fiber Industries, Salisbury, NC, to K. Meardon, Pacific
Environmental Services, Inc., Durham, NC, November 22, 1982.
Environmental Protection Agency, Research Triangular Park, NC, October 27, 1980.
16. Final Trip Report To Monsanto 's Polyester material Plant, Decatur, Alabama, Energy and Environmental
Analysis, Oshawa, NC, Aug 27, 80.
16. Created communication coming from D. Perry, Fiber Companies, Salisbury, NC, to E. Meardon, Pacific cycles
Environmental Providers, Inc., Bowmanville, NC, Feb 11, 1983.
Roy, U. S. Epa, Research Triangle Park, NC, August twenty-five, 1988.
Farmer, U. T. Environmental Protection Agency, Exploration Triangle Recreation area, NC, Sept 4, 1984.
20. Drafted communication via A. Big t. Roy, Allied-Signal, Petersburg, VA, to K. Meardon, Pacific
Environmental Providers, Inc., Durham, NC, September 18, 1989.
Essay in Market-Based Strategies in Global Tv: Interesting Opportunities in a Fast-Expanding Marketplace
draw:g ANNOUNCEMENT: " I, the undersigned, hereby declare that assignment can be ..