Polyethylene (PE) Film is a widely used polymeric packaging material crafted from polyethylene resin, standing out as one of the most consumed plastic films globally—accounting for over 40% of the total consumption of plastic films. Boasting exceptional flexibility, reliable moisture resistance, and excellent heat - sealability, coupled with easy processing and cost - effectiveness, it has become an indispensable material across numerous industries. Below is a detailed breakdown of its key categories, core features, applications, and usage guidelines:
Based on density differences and polymerization processes, PE Film is mainly divided into three mainstream types, each with unique properties to meet diverse application needs:
Low - Density Polyethylene (LDPE) Film
It is produced via high - pressure polymerization, with a density ranging from 0.910 - 0.925 g/cm³. This film is soft, flexible, and transparent, featuring non - toxicity and odorlessness. It excels in water resistance, moisture protection, and heat - sealing performance. However, it has relatively low tensile strength and poor oil resistance, and is not suitable for packaging oil - rich or oxidation - prone foods. Its thickness usually falls between 0.02 - 0.1 mm, making it easy to fold and process without cracking.
High - Density Polyethylene (HDPE) Film
Manufactured through low - pressure polymerization, it has a higher density of 0.94 - 0.965 g/cm³. Presenting a milky semi - transparent appearance with low surface gloss, this film outperforms LDPE Film in tensile strength, heat resistance, oil resistance, and chemical stability. It can be made as thin as 0.01 mm, known as "paper - like film" due to its soft texture similar to silk paper. Its drawbacks lie in inferior transparency and relatively poor airtightness, which limits the shelf life of packaged food.
Linear Low - Density Polyethylene (LLDPE) Film
A newer variety with a linear molecular structure and a density of 0.915 - 0.925 g/cm³. It combines the flexibility of LDPE Film and the rigidity of HDPE Film, boasting higher tensile strength, puncture resistance, and elongation. It is not easy to tear even under stretching or rough handling, and has a wide adjustable range of injection molding temperatures, making it suitable for scenarios requiring high durability.
PE Film's versatility enables its application across multiple sectors, covering product packaging, surface protection, and logistics binding:
Food and Daily Necessities Packaging: LDPE Film is extensively used for packaging fresh fruits, vegetables, baked goods, and frozen foods, as it can retain freshness and prevent moisture loss. HDPE Film is commonly made into shopping bags, food packaging bags, and garbage bags.
Surface Protection: It serves as a protective layer for various products during production, transportation, and storage. The applicable items include stainless steel plates, aluminum profiles, high - end furniture, electrical cabinet casings, computer shells, automobile lamps, decorative panels, and coated glass. It effectively prevents surface contamination, scratches, and corrosion, maintaining the products' pristine appearance.
Logistics and Industrial Use: LLDPE Film is the preferred material for pallet wrapping in warehousing and logistics. Its strong puncture resistance and tensile strength ensure stable packaging of goods during transportation. Additionally, it is used in manufacturing cables, hoses, and composite film inner layers.
