6400-B Sycamore Canyon Blvd
Riverside, CA 92507
Phone: 951-214-6380
Fax: 951-214-6387
Call us at: 1-877-593-2182

Plastics Used in Blow Molding

Thermosets and thermoplastics are the two most common types of plastic used in blow molding. The main difference between them is the way they process heat: under high temperatures, thermoplastics will melt, whereas thermosets will solidify.

Characteristics of Plastics

This is because under heat, a thermosetting polymer cannot be weakened; its three-dimensional chain will cross-link and strengthen irreversibly. On the other hand, thermoplastic polymers hold the shape of a one-dimensional string of monomers whose bonds weaken rapidly under heat, thus causing the plastic to melt and allowing it to be re-shaped. When cooled, the thermoplastic bonds will strengthen and the plastic will re-solidify.

Needless to say, many molding processes require the use of thermoplastics or thermosets, including extrusion blow molding.

Extrusion Blow Molding

Extrusion molding is an industrial process that melts raw thermoplastics in the form of granules. The plastic is fed into a machine through a revolving chamber, which will melt it and force it through something called a “die,” which is similar to a mold in that it provides shape, but it does so by cutting materials as they are forced through. The finished products are often long and rough shapes such as rods, sheet metal, or pipes.

The Process of Molding Plastic

Blow molding is the process of molding plastic into a hollow shape. It can be done through either an Extrusion method. In the Extrusion method, the melted plastic is forced through a die to be shaped like a tube. The product’s mold then entraps the tube. From the top, a blow pin is inserted through the tube and air pressure inflates the plastic into the hollow shape of the mold it is trapped in. In the Injection method, the process is very similar except a die is not used to form the tube; the tube is formed when melted plastic is directly injected into a mold made specifically for it.

Our Blog

February 6, 2019
Western Case Shares The Variety of Products Created with Blow Molding
Riverside, CA – Blow molding manufacturer, Western Case,
February 4, 2019
What Kind of Products are Produced by Blow Molding?
According to the latest data, nearly 50% of all manufactured
January 23, 2019
What Hard Plastic Carrying Cases Can Protect Equipment?
For valuable and sensitive equipment there are three
December 31, 2018
How to Measure an Equipment Carrying Case and Understand ATA Specifications
Using a carrying case is an excellent answer for protecting,