Bubble Bags
The main material is low-density polyethylene (LDPE), also known as high-pressure polyethylene. It is a milky white, non-toxic, odorless, waxy granular plastic with excellent flexibility, stretchability, and cushioning properties.

Material Properties
Low-density polyethylene (LDPE) is the core material of bubble bags. Its characteristics include:

Physical Properties: Density 0.91-0.93 g/cm³, melting point 110-115°C, processing temperature 150-210°C, and milky white, translucent waxy granules.

Chemical Properties: Resistant to alkalis and common organic solvents, but poorly resistant to oils and fats. It is susceptible to aging due to long-term exposure to UV rays or high temperatures.

Functional Advantages: The air bubbles formed by the film provide shock absorption, wear resistance, sound insulation, and thermal insulation. ‌

Production Process‌

Bubble bags are made from LDPE, primarily through two high-pressure polymerization processes:
Tube process: Reaction pressures range from 200 to 350 MPa, single-pass conversion rates from 20% to 34%, and a broad molecular weight distribution.

Agitator process: Reaction pressures range from 110 to 250 MPa, single-pass conversion rates from 20% to 25%, and a narrow molecular weight distribution.

Common Types‌

Depending on the composite material and intended use, bubble bags are primarily categorized as follows:
Naked bubble bags: Made from pure LDPE bubble film, offering high transparency.

Kraft paper composite bubble bags: The outer layer of kraft paper is easy to write on and print on, while the inner bubble film provides cushioning and shock absorption.

Anti-static/static conductive bubble bags: Specially treated to achieve a surface resistivity of 109-1011Ω, making them suitable for electronic product packaging.