Basic polyester chemistry

Polyester: Basic Polyester Chemistry Polyester Content: Products made of Polyester Properties of Polyester What is Polyester - Definition- Production of Polyester Side reactions Products made of Polyester Example: Clothes Vlies Jacket Jacket T-Shirt Trikot Thermo shirt Gloves Cap Sweater Windcheater Waist coat Rain coat Products made from Polyester Example: PET bottles Products made from Polyester Example: Film Products made from Polyester Example: Film UV-stabilized PET film Transparent PET film Barriere PET-Folie Metal coated Flame retardand PET film PET film Cover PET film Electro isollated PET film Thermo shrinkage PET film White opal film Products made from Polyester Example: Film Products made from Polyester Example: Tire cord Products made from Polyester Example: Canvas Produkte made from Polyester Example: Tennis racket tension Polyester Granulat: Specification of Polyethylene terephthalate (PET): Intrinsic viscosity (IV) adjustable 0.62 - 0.68 dl/g (measured acc to DIN 53228 in Phenol/o-Dichlorobenzene 1:1 at 25° C) Variation of intrinsic viscosity max ± 0.01 (measured in the laboratory) Melting point Variation of melting point max COOH-endgroups max DEG content adjustable Variation of DEG content max 259 ° C  ° C 25  mval/kg 1.1 - 1.3 wt %  0.1 wt % Color number L*- value 80 (CIE-LAB method) b* -value max + 3.5 DSC measurement of amorphous PET sample: 129.9° C 129.4° C Explaination: 129.0° C 126.6° C - Black: direct measured 146.7° C - Red: 145.4° C - Green:measured after hours - Blue: measured after hours measured after hours Depending on the time of DSC-measuring, 256.4° C 256.0° C 255.6° C 255.6° C after chips production, the 2.nd crystallization peak gets smaller and will finally disappear How small is a PET molecule ? (1313 pm) effectiv ~ 1000 pm 72 154 278 154 143 143 154 O HO - C - 143 At a number of 100 monomer units per chain length, i.e at a polymerisation 72 degree (DP) of 100 correspond the O effective length of a PET molecule - C - O - CH - CH - O - H n Monomer approx 100‘000 pm 100‘000 pm correspond to a length of 100 nm or 0.1 um or 0.0001 mm 0.01 mm -> i.e still 100x smaller 0.1 mm mm How long is gram of PET, if all molecule chains within of gram are connected together: (1313 pm) effectiv ~ 1000 pm 72 154 278 154 143 143 154 O HO - C - 143 72 O A PET molecule with 100 monomer units per chain length, i.e the degree of polymerisation (DP) of 100 has a length of - C - O - CH - CH - O - H n Monomer approx 100‘000 pm or 0.0001 mm -7 or x 10 m 23 molecules mole of a component contains 6.02 x 10 mole of PET with PD = 100 has a molecular weight of approx 19308 g 23 19308 g PET contains 6.02 x 10 moleculese 23 19 g PET contains 6.02 x 10 / 19308 = 3.12 x 10 molecules -7 PET molecule (DP = 100) has a length of x 10 m 19 molecules has a calculated length of: g PET with 3.12 x 10 19) -7 (3.12 x 10 x (1 x 10 )m = 12 3.12 x 10 m, or 3.12 x 10 km How long is gram of PET, if all molecule chains within of gram are connected together: km g PET has a length of 3.12 x 10 This corresponds to a distance of approx 78‘000 mal around the earth Earth circumference: approx 40‘074 km or a distance of approx 8‘000 times from earth to the moon Earth to moon: approx 384‘000 km or a distance of approx 20 x from earth to the sun Earth to sun: approx 149‘680‘000 km The molecules of g PET connected together corresponds to: - a distance of approx 78‘ 000 x around the earth - a distance of approx 8‘ 000 x earth to the moon - a distance of approx 20 x earth to the sun Side reactions By producing of Polyester also side reactions take place, means: by the reaction of terephthalic acid with ethylene glycol, not only polyethylene terephthalate (PET) and water are build, also many by-products are formed: The most formed by-products are: - Oligomeres (OM) approx 1.5 wt-% - Diethylene glycol (DEG) approx 1.1 wt-% - Acetaldehyde (AA) approx 0.18 wt-% (~ 1800 ppm) - 2-Methyl-1,3-dioxolane (2-MDO) approx 0.18 wt-% (~ 1800 ppm) as well as: While OM and DEG remain in the polymer, - 1.4-Dioxane (1.4-DO) the AA and 2-MDO will be driven out - Acetic acid (HAc) mostly - Derivates of terephthalic acid By-products: Building of Oligomers (OM) O O - C - OH HO - C - O HO - C - + HO - CH - CH - OH O O - C - O - CH - CH - O - H O + O O - C - O - CH - CH - O - H OM-Content in the PET: - C - O - CH - CH - O - C - C - HO H HO catalyst X = 2: Trimers ~ 0.95 % / mp ~ 319° C X = 3: Tetramers ~ 0.35 % / mp ~ 325° C - - catalyst C C - O - CH - CH - O - O O X By-products: Building of Diethylene glycol (DEG) catalyst HO - CH - CH - OH + HO - CH - CH - O - CH - CH - OH H O DEG-Content in the PET: approx 1.1 % O HO - C - O HO - C - O O CH O - C - - C - O - CH - CH - OH - CH - O - O O -C - C - O - CH H - - CH - O - O - C - O - CH - CH - O - H O H - C - O - CH - CH - O - By-products: O R - C - O O R' - C - O - CH - CH - O - O O + - C - O - CH CH HO - C - O + R - C - O H O + R - C - HO - CH - CH - OH O + R - C - O R' - C - O - CH - CH - O - O + CH - COH - C - OH O CH - C - O - CH - COH - CH - OH + O - C - HO - CH - CH - O O AA-Building in PET: ~ 4000 ppm O - C - - C - O - CH - CH - O - O R - C - Building of Acetaldehyde (AA) O - C - O - R'' O - C - - C - O - CH - CH - O O - C - O - R'' + CH - COH By-products: Reaction of Ethylene glycol (EG) with Acetaldehyde (AA) HO - CH - CH - OH CH - COH + O H Acetaldehyde (AA) O HO - CH - CH - OH + CH CH - COH CH - CH CH + H O O 2-Methyl-1.3-dioxolane (2-MDO) O HO - CH - CH - OH CH CH O CH - COH + ½ O CH CH + O H 1.4-Dioxane (1.4-DO) CH - COOH Acetic acid (HAc) Degradation reactions of Polyester O R - C - O R' - C - O - CH - CH - O - - C - - C - O - CH - CH - O - O + H O O O R - C - O O O R' - C - O - CH - CH - O - - C - - C - O - CH - CH - OH + HO Hydrolytic Degradation O R - C - O O - C - O - CH CH Thermal Degradation O R - C - + O R' - C - O - CH - CH - O - HO - C - O - C - CH + ½ O Oxidative Degradation + CO .. .Polyester Content: Products made of Polyester Properties of Polyester What is Polyester - Definition- Production of Polyester Side reactions Products made of Polyester Example:... opal film Products made from Polyester Example: Film Products made from Polyester Example: Tire cord Products made from Polyester Example: Canvas Produkte made from Polyester Example: Tennis racket... Windcheater Waist coat Rain coat Products made from Polyester Example: PET bottles Products made from Polyester Example: Film Products made from Polyester Example: Film UV-stabilized PET film Transparent