Analysis on the development technology of plastic

2022-08-16
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Food packaging: analysis of the development technology of "plastic beer bottles"

compared with traditional glass beer bottles, plastic beer bottles have obvious advantages of light weight, not easy to break, not easy to explode, and low storage and transportation costs

at present, the plasticization of beer bottles has become an internationally recognized trend. Equipment suppliers in various countries are stepping up research and seeking breakthroughs in the development of plastic beer bottles

basic conditions for beer packaging with plastic bottles:

1 Ensure that the stored beer will not deteriorate within the validity period

2. It has the competitiveness that the production cost of beer is not higher than the original

3. For the original production site, the production line is not changed much, and the transformation time is not long. It is best to be able to achieve dual-use of one machine

therefore, the selection of raw materials and bottle making technology for plastic beer bottles is extremely important. First of all, the bottle must have high barrier to gas (i.e. prevent oxygen from entering and carbon dioxide from seeping out) and Guangya aluminum's sprayed aluminum profile products have passed the quality certification of European famous aluminum profile powder coating QUALICOAT, which can block ultraviolet light. It is better to absorb the oxygen in the bottle. At present, manufacturers have added oxygen absorbing materials to the gasket of the bottle cap, and even added oxygen absorbing materials to the interlayer materials when blowing multi-layer bottles. In addition, the bottle mouth and cap should be sealed tightly without any air leakage

types of plastic beer bottles at home and abroad

1, polyethylene terephthalate (PET). At present, most of the plastic used in soft drink packaging is pet. When pet plastic is used to make beer bottles, due to its poor gas barrier, it is easy to make beer deflated and oxidized. Therefore, the storage period of beer in bottles made of pet is relatively short. Foreign pure PET bottles are only used to hold cheap beer stored for a short time. In addition, untreated pure PET bottles have poor temperature resistance and scratch resistance. PET bottles cannot be reused after recycling, but can only be recycled for other purposes

2. Pen bottle. Pen bottles are several times better than PET bottles in terms of heat resistance, UV resistance, scratch resistance and long storage time after beer filling. Pen has excellent heat resistance, and there is no problem after minutes of water spray sterilization below 80 ℃

3. Plastic bottles produced by multi-layer composite or coating and modification technology

at present, most plastic beer bottles in the foreign market are made of coating or modification and multi-layer composite. The modified plastic bottles and the coating technology on the inner wall of PET plastic bottles, especially the beer bottles with multi-layer plastic composite, have entered the quantitative production experiment. Most of the so-called pet multi-layer composite plastic bottles have a three-layer structure, and the outer layer is pet plastic; The middle interlayer is EVOH or nano nylon, which is rarely used because pen is too expensive; The inner layer is also made of PET plastic. Modified plastics, such as nano pet, are seldom used for bottle blowing production because of the high production temperature of modified PET, which is easy to produce crystallization

advantages and disadvantages of plastic bottles

1. Plastic bottles made by one-step blowing have less mechanical scars, good air tightness between bottle mouth and bottle cap, small air leakage and water seepage ratio, high transparency and beautiful appearance. The biggest technical problem is that it is difficult to control the uniformity of the bottle wall, the thickness difference is large, and it is easy to produce bulge deformation

2. The plastic bottle blown by two-step method has more mechanical scars, and the transparency is slightly worse than that of one-step method. In the two-step blowing of plastic bottles, the preform of the bottle is first injected, prefabricated and shaped, and then sent to the next process for secondary heating and blowing. Mechanical trauma is inevitable during the transportation of bottle blanks in the hopper and storage, and the mutual friction of bottle blanks causes the damage of bottle blanks and blank mouths. Therefore, the air tightness of bottle caps and bottle mouths is poor, and the air leakage rate is higher than that of one-step blowing. The advantage is that the bottles blown out by this technology are tested with an ultrasonic thickness measuring instrument with a year-on-year drop of 91%. These bottles have uniform walls and small thickness error, and it is not easy to produce bulge deformation after filling beer drinks. However, the investment of this equipment is large and the operation risk is high

3. Due to the plastic characteristics of PET plastic bottles, when filling beer drinks with plastic bottles, special attention should be paid to whether the whole line uses the lubricating fluid that meets the standard. Only the lubricating fluid that meets the standard can ensure that PET plastic bottles are not damaged by chemical factors. Otherwise, the bottom of the plastic bottles may burst or leak due to the high acid or high alkali chemical damage of the lubricating fluid after filling or even after packing, This phenomenon is particularly common in filling carbonated water

4. Precautions for PET plastic beer bottle capping. When sealing the metal cap, it is best to know the material of the metal cap clearly. For example, if the aluminum metal cap is used for bottle sealing, its sealing and sealing tightness will not have much problem. When the bottle cap is made of iron metal, special attention should be paid to whether the metal cap of the crown cap will bounce off due to the mechanical rebound of the metal material after its claw is pressed against the bottle. If there is rebound and dislocation, the sealing effect of its packaging must be poor. Once the packaging bottle encounters light, heat and vibration, it will shrink or expand under the action of external force, which will move the sealing joint between the bottle mouth and the bottle cap, resulting in air leakage and liquid seepage

5. Plastic coating technology has the advantages of good gas barrier and strong UV barrier, but its disadvantage is that it is not resistant to impact. When encountering strong vibration, the liquor will be polluted due to the separation and falling off of its coating, which will cause physical injury to those who consume it into three kinds of manual wood-based panel universal testing machine

6. Due to the soft and thin wall of plastic bottles, when filling beer drinks, due to its stiffness, it can not withstand vacuum treatment. Long tube filling method is widely used for oxygen removal in bottles, and carbon dioxide gas is added to expel oxygen. When using plastic bottles for beer beverage packaging, it is necessary to add a special bottle sorting machine for PET plastic bottles when filling beer beverages. It can also be produced simultaneously by combining the bottle blowing machine with the beer beverage filling line. Beer beverage filling in view of the different technical requirements of plastic bottles and glass bottles, the former uses the hanging bottleneck to supply bottles by airflow, and most of the bottle closures used are plastic and metal, and the capping methods are basically fork pressure rotary sealing and fork pressure claw sealing. The latter is supplied by the conveying chain and star wheel. The filling and capping are carried out by the support of the bottle. The capping methods are basically plastic and metal, and the capping methods are spinning and clawing

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