Leading Urethane Molder Manufacturers

What Is Urethane Molding?

Polyurethane can be processed easily, making it more efficient during the fabrication of industrial parts and consumer goods. Polyurethane molding helps to achieve complex geometries and tight tolerances.

Properties of Urethane Molders

Some of the properties of urethane molders include:

Hardness

Hardness is defined as how a material resists surface deformation. For example, urethane shows a high hardness number on a durometer, as illustrated in the figure below.

Abrasion Resistance

Polyurethane materials are blended to have a low coefficient of friction, a high tear strength, and great sliding abrasion resistance. Polyurethanes with good resilience are used for impingement abrasion.

Resilient polyurethanes can yield elastically, allowing the forces from the impacting particles to be evenly spread on the surface.

Tear Strength

Tear strength is the capacity of polyurethane to withstand applied tensile forces. The tensile force tends to tear the material and continue the tear in the body of the specific material. Polyurethane is well known for its good tear strength and abrasion resistance.

Machinability

This property allows polyurethanes to be designed and shaped into any desired geometries. Machinability has to do with removing all imperfections on the product surface.

Chemical Resistance

Polyurethanes have chemical resistance characteristics that depend on the polyol being used. There are ether-based and ester-based systems. The former is resistant to water, while the latter resists solvents, oils, and petroleum compounds.

Raw Materials Used in Polyurethane Molding

Polyurethanes are made of different components. The primary constituents are diisocyanates and polyols. Some of the components used are curatives. Additives are also part of the materials, which bring about some unique properties of the formulation of specific polymers of polyurethane. Other groups of components that help in producing gasses for making the foam structure are catalysts, blowing agents, and surfactants.

Polyol

These are organic molecules that have one or more groups of hydroxyl. The ones used in urethane casting are polyesters or polyether types.

Diisocyanate

Diisocyanate forms the resin part of the system of polyurethane. It is usually grouped into two types: aliphatic and aromatic. The aliphatic type has a yellowing appearance, and its reactivity is very low. This makes it useful in coatings for chemically-resistant materials. Their application is mostly found in polyurethane films, coatings, and castings where color stability is needed.

The aromatic type stands for over 90% of the total diisocyanate consumption. It is further divided into Naphthalene, Toluene, and Methylene diisocyanate.

Types of Urethane Molding Processes

Types of urethane molding processes include:

Injection Molding

It is a process of making polyurethane moldings. The process involves melting and heating powdered or pelletized polyurethane to make it flow. Afterward, the polyurethane is driven by a reciprocating ram-type screw into a hard mold or tool.

Pressure at high atmospheres is then used to drive the polyurethane into the crevices and cavities of the mold. The mold is then machined, followed by the curing process, before the polyurethane is cooled and released.

Compression Molding

Compression molding uses a mold with two halves, the upper and the lower. The latter receives a compound polyurethane mass, and the two are compressed afterward.

This forces the polymer mass to flow with respect to the design or shape of the mold. A homogeneous product is formed as a result of the gas vented out. After the molding process, the product goes through curing and cooling before release.

Rotational Molding

Rotational molding is a procedure mostly used when producing hollow seamless products. Powdered polyurethane is loaded into a mold which is heated and rotated to melt the polymer. The material then coats the mold surface.

Blow Molding

Blow molding involves creating hollow products by inflating a softened pre-form in the mold.

Casting

Casting involves the injection of polyurethane and resins into a soft mold made of silicone elastomer. It has similarities to injection molding, although they may differ in the use of hard metal molds.

Applications of Urethane Molders

Urethane moldings are commonly used and applied in:

• Furniture for underlays, cushions, and covers
• Building insulation in the construction industry
• Bumpers, fenders, and bushings for the automotive industry
• Manufacturing wheels, rollers, and cams

Choosing the Proper Urethane Molder Company

To make sure you have the most beneficial outcome when selecting a urethane molder, it is important to compare at least 4 to 5 urethane molders using our urethane molding directory. Each urethane molder has a business profile page that highlights their areas of experience and capabilities and a contact form to directly communicate with the company for more information or request a quote. Review each urethane molder website using our proprietary website previewer to get an idea of what each company specializes in, and then use our simple RFQ form to contact multiple urethane molders with the same message.