Blown Film Polyethylene

Updated: 2026-07-23

Overview

Polyethylene blown film is manufactured through a continuous extrusion process where molten polyethylene is extruded through a circular die, inflated into a bubble, then cooled and flattened into rolls. This versatile material dominates the flexible packaging market due to its excellent balance of strength, flexibility, and cost-effectiveness. The blown film process allows for precise control over film thickness (typically 10-200 microns) and width (up to several meters). Manufacturers can adjust properties by blending different polyethylene types (LDPE, LLDPE, HDPE) and incorporating additives for UV resistance, anti-fog properties, or improved tear strength.

Physical and Chemical Properties

The physical properties of polyethylene blown film vary significantly based on resin composition and processing parameters. LDPE-based films offer higher clarity and flexibility, while HDPE blends provide greater stiffness and tensile strength. All variants demonstrate excellent moisture barrier properties and resistance to most chemicals except strong oxidizers. Key mechanical properties include puncture resistance (essential for packaging applications) and elongation at break (typically 300-1000%). Optical properties range from highly transparent films for display packaging to translucent or opaque films for industrial applications. The material maintains stability across a wide temperature range (-60°C to 80°C for most grades).

Main Applications

Polyethylene blown film serves three primary market segments: packaging (60% of consumption), agriculture (25%), and construction (15%). In packaging, it's used for food bags, shrink films, and protective packaging. Agricultural applications include greenhouse covers, mulch films, and silage bags. Construction uses encompass vapor barriers and temporary weather protection. Specialty applications include medical packaging (using ultra-clean PE compounds), anti-static films for electronic components, and high-barrier films with additional coatings for extended shelf-life packaging. The material's recyclability (under resin identification code #4) makes it increasingly important in sustainable packaging solutions.

Safety and Storage

As a chemically inert material, polyethylene blown film presents minimal health risks in normal handling. Processing at high temperatures may release volatile compounds requiring proper ventilation. The film poses a choking hazard if ingested and should be kept away from children in sheet form. For optimal shelf life (typically 12-24 months), store rolls in a cool (below 30°C), dry environment away from direct sunlight. Stack rolls horizontally to prevent deformation, with maximum stacking height according to the manufacturer's specifications. Protect film edges from damage during handling to maintain quality.

B2B Procurement Guide

When sourcing polyethylene blown film, clearly specify: film thickness (in microns or gauge), width (layflat or tubular dimensions), resin composition (LDPE/LLDPE/HDPE ratio), and any special additives. Request technical data sheets confirming mechanical properties and food-contact compliance if applicable. For large-volume purchases (typically >5 tons), consider direct procurement from film extruders rather than distributors. Evaluate suppliers based on extrusion capabilities (multi-layer coextrusion for advanced applications), quality control systems (ISO certification preferred), and ability to provide customized solutions. Request samples for sealability and puncture resistance testing before bulk orders.