Introduction to the classification of general plastics for blow molding machinery

2019-02-14 08:37:48

Plastic PVC is also a general-purpose plastic for blow molding machinery with good induction function and low price, and it has many additives. It can adjust the formula, and the large undulation also changes the function of the product, for example, it can be added less or not. A plasticizer is added to produce a rigid plastic polyvinyl chloride product. Hard plastic PVC products have outstanding rigidity and good resistance to water and moisture, and oxygen, carbon dioxide and nitrogen permeation. Its oil resistance and transparency are also significantly better than polyolefin plastics. However, it is difficult to reclaim and use the discarded materials after packaging, and it is relatively simple to differentiate when the furnace is recycled. When burning and treating, substances such as hydrogen chloride that damage the environment will occur, and energy is consumed. Therefore, plastics The use of PVC in packaging has been bound, and with the continuous improvement of environmental awareness, its use in packaging has gradually replaced the trend of other plastics.

Among several plastic polyethylenes, high-density plastic polyethylene is the best mechanical strength of plastic polyethylene. The isolation of water vapor is the best among various plastic guesses, but in several plastic polyethylenes. Among them, it is the worst type of softness and transparency. When soft and transparent products are required, low-density plastic polyethylene should be used. The mechanical strength of linear low-density plastic polyethylene is high-density plastic. The greatest strength between ethylene and low-density plastic polyethylene is its high puncture resistance, high tear propagation resistance and excellent stress crack resistance. In addition, its heat sealing function is superior to high density plastic polymerization. Ethylene and general low-density plastic polyethylene, therefore, it is an outstanding substrate for film, one of its primary drawbacks is that the molding process is less advanced.

Polypropylene and propylene copolymers, polypropylene and plastic polyethylene, are typical polyolefin polymers, so they have many similar functions, such as good chemical stability, non-toxic, odorless, tasteless, and reliable cleaning function. Compared with plastic polyethylene, the primary advantage of polypropylene is that it has good heat resistance and can be used at temperatures up to 120 degrees. Therefore, a composite bag with propylene as a heat seal layer is used for retort sterilization. In addition, the strength of polypropylene is significantly higher than that of plastic polyethylene. One of the biggest defects in the function of polypropylene is its low temperature resistance. The polypropylene homopolymer has a large brittleness at 0 degree, and a small amount of ethylene and propylene. The copolymer can significantly improve the cold resistance of polypropylene, but the heat resistance is also correspondingly reduced.

Ethylene-vinyl acetate copolymer is also a kind of ethylene polymer used in packaging. Its price is slightly higher than that of plastic polyethylene. However, it is still a cheaper type in plastic guessing. It is resistant to cold with the addition of vinyl acetate. Sex, softness, heat sealability improvement, transparency improvement, but when the vinyl acetate content exceeds 10%, it can produce sourness, and it is not suitable to directly touch food.

Hollow Blow Molding Machine Hollow Blow Molding Machine The thermoplastic in the general plastic guess has a balanced function, convenient forming and processing, convenient returning and abandoning materials, and the product price is lower than the first grade, and many are used for plastic packaging materials. The primary types are plastic polyethylene and ethylene copolymers, which include high density plastic polyethylene, low density plastic polyethylene, linear low density plastic polyethylene, ethylene, vinyl acetate copolymer, and the like.

As a plastic packaging material, it is very similar to plastic polyethylene. Polypropylene has excellent moisture resistance and moisture resistance, but it is inferior to non-polar gases such as oxygen, carbon dioxide and nitrogen. When the product needs to be stored in oxygen, it needs to be used. The so-called insulating plastic packaging material is used for packaging, and the composite product of polypropylene (plastic polyethylene) and insulating plastic packaging material may be used as the plastic packaging material.

Plastic polyethylene plastic is a typical polyolefin compound, non-toxic, odorless, tasteless, reliable in cleaning function, acid-proof, alkali, salt and various chemicals, stable in function; balanced in physical and mechanical functions, excellent in moisture and moisture resistance. Its molding processing function is convenient, it can be conveniently made into various packaging plastic products such as plates, films, containers, flat wires, etc., and the price is low, so it is widely used in packaging. As a plastic packaging material, its primary defect is Poor oxygen barrier.