With the development of production equipment and raw ma […]
With the development of production equipment and raw materials, plastic packaging has been widely used in various fields. In recent years, compared with glass bottles, this packaging form, which has the characteristics of lighter weight, less fragile, easy to manufacture and sterilize, easy to seal, and low cost, has been widely concerned by pharmaceutical companies and has been developing rapidly.
Raw materials for plastic bottles
The raw materials of medical plastic bottles must meet the medical and health requirements. Common plastic varieties are: polyethylene (PE), polypropylene (PP), polystyrene (PS), polyester (PET), etc. Polyethylene (PE) has corrosion resistance and can be chlorinated. Polyethylene is divided into high density (HDPE), low density (LDPE) and linear low density (LDPE). HDPE has high melting point, hardness and strength, low water absorption, good processability and radiation resistance, and is often used in the production of plastic bottles for tablets; LDPE has good flexibility, elongation and impact strength, and can be used Plastic bottles for eye drops; LDPE has high impact strength, fatigue resistance and abrasion resistance, and is rarely used in pharmaceutical packaging.
Polypropylene (PP) has a low density, and its strength, hardness and heat resistance are better than high-density polyethylene, but it becomes brittle at low temperatures, not wear-resistant, and easy to age. However, corresponding additives can be added for modification, and the performance level of HDPE can be reached after modification.
Polystyrene (PS) is colorless and transparent, with light transmittance second only to plexiglass, good colorability, water resistance, chemical stability, and general strength. However, PS is brittle, prone to stress embrittlement, and is not resistant to organic solvents such as benzene and gasoline, so it is rarely used in the field of pharmaceutical packaging. But after modification, the impact resistance of the material can be greatly improved.
As a medicine packaging container, PET has many advantages. First of all, PET bottles are light and strong, and their strength and elasticity are significantly higher than those of plastic bottles made of other plastic materials. They have better performance in blocking water vapor and oxygen in commonly used plastics; PET bottles have good chemical resistance and can be used. It is suitable for the packaging of all items except strong alkalis and some organic solvents, and is suitable for making thin-walled, light-weight, and high-strength pharmaceutical packaging bottles. Therefore, PET bottles have a tendency to replace traditional glass bottles.