What Is Expanded Polystyrene (EPS)

Expanded polystyrene (EPS) is a lightweight and rigid foam material. It is a material of choice for the packaging and construction industry. It provides cost-effective solutions and energy-efficient insulation. It also acts as a cushion transport packaging material for shock-sensitive goods.

 

1. What is expanded polystyrene (EPS)?

Expanded PolyStyrene (EPS) is a white foam plastic material. It is produced from solid beads of polystyrene. It is used for packaging and construction. It is a closed-cell, rigid foam material.

 

2. How is expanded polystyrene made?

The conversion of expandable polystyrene to expanded polystyrene is carried out in three stages:

Pre-expansion, Maturing/Stabilization, and Molding

Polystyrene is produced from crude oil refinery product styrene. For manufacturing EPS, the polystyrene beads are impregnated with the foaming agent pentane. Polystyrene granulate is prefoamed at temperatures above 90°C.

This temperature causes the foaming agent to evaporate. Hence inflating the thermoplastic base material to 20-50 times its original size.

After this, the beads are stored for 6-12 hrs allowing them to reach equilibrium. Then beads are conveyed to the mold to produce forms suited as per application.

During the final stage, the stabilized beads are molded in:

oeither large blocks (Block Molding Process)

oor designed in custom shapes (Shape Molding Process).

The material can be modified by the addition of additives such as flame retardant to further enhance the fire behavior of EPS.

 

3. What are the fetures of EPS?

EPS is a lightweight material with good insulation characteristics

Mechanical strength – Flexible production makes EPS versatile in strength. This strength can be adjusted to suit specific applications. EPS with high compressive strength is used for heavy load-bearing applications. For void-forming EPS, lower compressive strength can be used.

Dimensional Stability – EPS offers exceptional dimensional stability. It remains virtually unaffected by a wide range of ambient factors.

Electrical Properties – The dielectric strength of EPS is approximately 2KV/mm. Its dielectric constant is measured in the frequency range of 100-400 MHZ. At gross densities from 20-40 kg/m3 the dielectric constant lies between 1.02-1.04. Molded EPS can be treated with antistatic agents to comply with electronic industry and military packaging specifications.

Water Absorption – EPS is not hygroscopic. Even when immersed in water it absorbs only a small amount of water. As the cell walls are waterproof, water can only penetrate the foam through the tiny channels between the fused beads.

Chemical Resistance – Water and aqueous solutions of salts and alkalis do not affect expanded polystyrene. However, EPS is readily attacked by organic solvents.

Weathering and Aging Resistance – EPS is resistant to aging. However, exposure to direct sunshine (ultraviolet radiation) leads to a yellowing of the surface

Fire Resistance – EPS is flammable. Modification with flame retardants significantly minimizes the ignitability of the foam and the spread of flames.

 

4. About us

Luoyang Dema Import & Export Co., Ltd. aims to provide high-quality, cost-effective products for global factories, plastic product manufacturers, and material distributors. Luoyang Dema Import & Export Co., Ltd. provides the best PP, PE, PVC, AVE, and ABS material solutions for plastic product manufacturers, wholesalers, distributors, distributors, factory owners, processing workshops, etc.

 

If you are looking for general plastic materials, please feel free to get the latest prices and quotations from Luoyang Dema Import & Export Co., Ltd. The sales team will reply within 48 hours.