If categorized by the thermal properties of the plastic. We can be divided into two categories.
1. thermoplastic plastic. (Thermoplastic)
polymer is the molecular structure of the polymer chain is a linear or branched short. Can be dissolved in a solvent of some kind. When the heat is weak. And molten liquid viscosity, since Tangled polymer molecules are able to pass through more easily when heated. And as it cools it hardens. The melting and cooling it. Can come forth without chemical and physical. Or structure of the polymer changed much. This plastic When the heat is weak. When the temperature drops to freezing. If the heating is weak. Can make it back to its original shape or change the other. The plastic properties of the same This plastic Molecular structure A long chain There is a connection between the polymer chains, as well, very little. Can be a melting Or when a very strong compression. The
original structure is not destroyed Examples of thermal plastic is poly ethylene, poly propylene copolymer styrene.
2. thermostat set routing. (Thermosetting)
polymer is a crosslinked network structure. Which will melt in the process of forming a first time. In this process, the chemical reaction occurs causing Gig of bonding between molecules. Make polymers that permanently shaped Can not melt when it gets hot again. And if it is overheating. Make bonds between atoms in a molecule broken. The material properties of the polymer no further.
, manufacturing plastic thermostat set to be different from thermoplastic plastic is plastic. In the first step the reaction polymerase polarization only partially. Is linked molecules occurs slightly. And can melt when heated. It can be molded under high pressure and temperature. When the product is shaped as desired. A constant temperature of about 200-300 ° C to obtain a reticulate structure, stable and strong. Can be removed from the product without waiting for the evening. The product will solidify within the mold. Therefore, the heating process.
plastics thermostat set back, making the material more rigid. Unlike plastics processing, thermo plastic, the heat makes the plastic soft and melting plastic thermostat set when done, can not be brought through melting and production of new products or recycled (recycle. ) again, and if it is too hot. Makes the plastic decomposition or combustion. Without melting Examples of this group, such as plastic Becker Lite and melamine etc..
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