What Is a Plasticizer?

What is a plasticizer?
Plastic manufacturing using plasticizers
Starting with the basics, a plasticizer is a low-volatility liquid or solid substance that is added to raw polymers such as plastics or rubber to increase its flexibility, make it easier to shape and mold, and reduce friction on its surface. When they are added to polymers, they work themselves into the polymer chain, acting as buffers between molecular fragments. Think about how the cartilage in the knee helps cushion the joint and helps the knee bend and move. Plasticizers work similarly, without plasticizers the material becomes stiffer, tougher, and more difficult to mold.

Four major families of plasticizers
More than 30,000 substances have been tested for use as polymer plasticizers, but only about 50 are currently available. Among them, they are divided into four families:

Phthalates, used to make plastics more flexible
Dicarbonates are used to mold PVC at lower temperatures;
Phosphates are used in the manufacture of flame-retardant materials.
Fatty acid esters are added to rubber and vinyl to improve flexibility.

Where are plasticizers used?
More than 8 million tons of plasticizers are used every year, most of which are added to polyvinyl chloride (PVC). Consider PVC—it’s a hard, rigid, brittle material used in water and sewer pipes, but it’s also used to make shower curtains, hoses, and cable covers. Without plasticizers (most commonly phthalates and fatty acid esters), PVC will remain rigid.

For everyday materials and objects:
Plastics containing plasticizers are found in almost every industry, including:

Medical thermoforming is used to make IV bags and flexible equipment;
Automotive thermoforming for molding flexible hoses;
The garment design makes the soles flexible and comfortable;
The telecommunications sector forms durable, low-friction, flexible casings to wrap wires and cables.
building use
Despite its name, plasticizers are also used in rubbers, adhesives, and most surprisingly, in concrete and stucco. Adding one to two percent plasticizer to concrete reduces water use, resulting in a stronger, easier-to-work substance, and the same idea applies to why it’s used in siding plaster. It uses less water, adds a little plasticizer to make it easier to work with and mix, and it dries in a fraction of the time of traditional mixed plaster.

Are plasticizers safe?
No other chemical has as much research support as plasticizers. Research has been conducted on how phthalates affect the environment, whether phthalates penetrate into indoor dust, and whether endocrine disruption from phthalate exposure is a factor of concern. The Registration for Evaluation, Authorization and Restriction of Chemicals (REACH), known as the world’s most comprehensive and stringent safety regulatory agency, has determined that nearly all plasticizers are safe, as has the FDA.

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