ZHONGSHAN XINRUN PLASTIC PRODUCTS CO., LTD.
ZHONGSHAN XINRUN PLASTIC PRODUCTS CO., LTD. ZHONGSHAN XINRUN PLASTIC PRODUCTS CO., LTD.
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Do You Know These Two Processing Characteristics Of Plastic Bottles?

Plastic bottles have certain processing and production methods. The main processing methods are extrusion, injection molding, calendering, blow moulding, moulding, lamination, casting and so on. The plastic bottle is made by blow moulding, which is to melt the plastic and press it into the special blow moulds. At the same time, there is air pressure inside the bottle, which will press the plastic onto the moulds to form the final product shape. Because the bottle is subjected to external pressure during the forming process, the internal stress of the bottle itself is inward, and the plastic will be softened when the heating temperature reaches a certain degree. The resistance to internal stress decreases, and the bottle decreases.

Plastic bottles have certain processing characteristics in processing and production. Processing according to certain methods ensures good quality and performance in production and processing. The processing characteristics of plastic bottles in terms of shrinkage and fluidity are described below.

Shrinkage rate

The shrinkage rate of reinforced plastics is smaller than that of ordinary pressed plastics. It mainly consists of heat shrinkage and chemical structure shrinkage. The first factor affecting shrinkage is plastic species. Generally, phenolic resin is larger than epoxy, epoxy phenolic resin and unsaturated polyester, among which the shrinkage of unsaturated polyester is the smallest. Other factors affecting shrinkage are the shape and wall thickness of plastic parts. The shrinkage of plastic parts will be small when the content of fillers and glass fibers is large, the shrinkage of plastic parts will be large when the content of volatiles is large. If the forming pressure is large, the shrinkage of plastic parts will be small when the loading is large, the shrinkage of thermal demoulding is larger than that of cold demoulding, and the shrinkage of curing inadequacy is larger. The shrinkage rate of plastic bottles is one of the important factors affecting the use of plastic bottles. It is necessary to reduce the shrinkage rate of plastic bottles in use, preventing important shrinkage phenomena in use and affecting the actual use effect.

Mobility

The fluidity of reinforcing materials is worse than that of ordinary pressure plastics. When the fluidity is too large, resin loss and glass fiber segregation are easy to occur. The forming pressure and temperature will increase remarkably when it is too small. There are many factors affecting liquidity. To evaluate the liquidity of a material, it is necessary to make a specific analysis according to its composition.