Plastic bottles have certain processing and production methods. The processing methods mainly include extrusion, injection molding, calendering, blow molding, molding, lamination, casting, and the like. The plastic bottle is blow molded, which is to melt and melt the plastic and then press it into a special blow mold. At the same time, there is air pressure inside, and the plastic is pressed onto the mold to form the final product shape. Because the bottle is formed. When the pressure is outward, the internal stress of the bottle itself is inward. When the temperature of the heating reaches a certain level, the plastic softens and the resistance of the internal stress becomes small, so the bottle becomes smaller.
Plastic bottles have certain processing characteristics in processing and production, and are processed according to certain methods of processing, ensuring good quality and performance in production and processing. The following describes the processing characteristics of plastic bottles in different aspects:
Reinforced plastics shrink less than conventional compression plastics and consist primarily of heat shrinkage and chemical structural shrinkage. The factors affecting shrinkage are first of all plastic types. Generally, phenolic is larger than epoxy, epoxy phenolic, unsaturated polyester, etc., and unsaturated polyester material has the smallest shrinkage. Other factors affecting shrinkage are the shape and wall thickness of the plastic part, and the thick wall shrinks greatly. The plastic contains filler and the glass fiber has a large shrinkage, and the volatile content is large, the shrinkage is large, the molding pressure is large, and the loading amount is large. The shrinkage is small, the hot mold release has a larger shrinkage than the cold mold release, and the curing is insufficient to shrink. The shrinkage rate of plastic bottles is one of the important factors affecting the use of plastic bottles. In use, the shrinkage rate of plastic bottles should be reduced to prevent important shrinkage during use and affect the actual use.
The fluidity of the reinforcing material is inferior to that of the general pressed plastic. When the fluidity is too large, the loss of the resin and the accumulation of the glass fiber are likely to occur. If it is too small, the molding pressure and temperature will increase significantly. There are many factors affecting liquidity. To assess the fluidity of a certain material, it must be analyzed according to the composition. Factors affecting liquidity.