Molecular Formula | C12H12O4 |
Molar Mass | 220.221 |
Density | 1.31 g/mL at 25 °C(lit.) |
Melting Point | 226 °C |
Appearance | Morphological pellets |
Storage Condition | -70°C |
Physical and Chemical Properties | The relative density of chemical properties is 1.31~1.55, and the water absorption rate is the lowest among thermoplastics, only 0.07%. It has excellent toughness and fatigue resistance, high impact strength, self-lubricity and wear resistance, small friction coefficient, but large notch sensitivity. Heat resistance, good weather resistance, flame resistance, but slow combustion. Good dimensional stability, excellent electrical performance, good arc resistance, but volume resistivity, high frequency media loss angle tangent value is large. Excellent chemical resistance, alcohol, ether, aliphatic hydrocarbon, acid and salt aqueous solution does not work. Resistant to carbon tetrachloride, swelling in dichloroethane, some swelling in aromatic hydrocarbons, acetic acid and ethyl acetate, and decomposition in concentrated nitric acid and sulfuric acid. Heat-resistant water, oil-resistant, but vulnerable to halogenated hydrocarbon erosion, poor hydrolysis resistance. The melt has low viscosity, excellent film-forming and formability, but has large shrinkage, good film flexibility, and high tear and yield strength. PBT molding can be used for injection molding, extrusion, blow molding, coating, welding, bonding, machining, vacuum forming, vacuum plating, finishing, etc. |
Use | For the manufacture of instruments, electrical, television, machinery and other parts |
WGK Germany | 3 |
Raw Materials | Antimony(III) oxide Pentabromophenyl ether |
Downstream Products | Antimony(III) oxide Antimony(III) oxide Pentabromophenyl ether Pentabromophenyl ether |
is a crystalline thermoplastic resin with a melting point of 224-227 ° C., a relative density of 1.31-1.55, and an extremely low water absorption of 0. 07%. High mechanical strength, tensile strength, elastic modulus and other mechanical properties are similar to those of engineering plastics such as polyoxymethylene and nylon. The friction coefficient is small, and the self-lubricating performance is excellent. The heat distortion temperature is 60 ℃ under 1. 82MPa load, but it can reach more than 120 ℃ under 0. 45MPa low load. Excellent electrical properties, the volume resistivity of l016 Q- cm, higher than the general engineering plastics. Arc resistance 190s, for other engineering plastics. Chemical resistance is very good, in addition to strong oxidizing acids such as concentrated nitric acid, concentrated sulfuric acid and alkaline substances on the production of its decomposition, other chemical media such as organic solvents, gasoline, oil, General detergent and other stability. PBT crystal surface gloss due to good, more stable size. It is worth mentioning that PBT resin is easy to flame retardant, with high efficiency flame retardant, can be made of mechanical properties do not decline, flame retardant grade UL-94V-O flame retardant plastics. The disadvantage is the sensitivity to notched impact.
The production method of PBT basically follows the production technology of PET, and only 1,4 butanediol is used instead of ethylene glycol. There are two kinds of Ester exchange method and direct esterification method.
The biggest difference between PBT and PET is that in the reaction process, 1,4 butanediol is easily dehydrated into tetrahydrofuran at high temperature, inhibiting the formation of tetrahydrofuran is one of the key control conditions in the production of PBT.
Mainly using injection molding process, can also be used to process film extrusion and other products. Before processing, the resin should be dried in a blast oven at 120 ℃ for 7~8H, and dried in a vacuum oven at 120 ℃ for 3~5H. In order to prevent moisture absorption, the Hopper is also kept warm, and the moisture content of the resin is required to be less than 0. 03% before processing. It is sensitive to the temperature of the cylinder, and if the optimum temperature is exceeded, the color of the product will become deep and brittle. Injection process conditions: cylinder temperature 230~250 ℃, injection pressure 4.OMPa, the mold temperature is 30 ℃, if the mold temperature is increased to 60~80 ℃, the joint strength and the surface gloss of the product can be improved, and the molding shrinkage rate of PBT resin is 1.2% ~ 2.3%, there is no directional difference in the performance of injection molded products.
PBT is known as one of the engineering plastics with excellent comprehensive performance. It is widely used in electrical, electronic, automotive, mechanical, instrumentation and other industries to make structural parts, such as the coil skeleton for TV, radio, connectors, bases, etc., are also suitable for structural components that require lubricity and corrosion resistance, such as gears, bearings, etc. After the flame retardant reinforcement of PBT, its performance is further improved, and it is more important in the above fields (see the section on the use of glass fiber reinforced PBT).
The product was packed in a polypropylene woven bag lined with a plastic bag with a net weight of 25kg/bag. The product should be placed in a clean and dry warehouse. Sun, rain and mechanical damage should be avoided during transportation. This product is not dangerous goods, non-toxic, tasteless, not easy to burn.
EPA chemical information | Terephthalic acid 1,4-butanediol polymer (26062-94-2) |