No matter what kind of project or use you need it for, you can’t go wrong with polyurethane sheeting. It works for all sorts of applications and comes in a wide array of colors and durometers, making it one of the most versatile materials available. Manufactured from thermoset urethane material, polyurethane flat sheet stock cannot be reheated or reformed, but can be machined.
Polyurethane sheets have a superior physical properties and quality so they can outperform products that are manufactured from rubber and many other traditional materials. Furthermore, polyurethane sheets can be used in a vast array of industries, which is why they are consistently in high demand. They are also the preferred choice because of their relatively low production cost and short manufacturing lead times.
In this blog post, we share everything there is to know about polyurethane sheets. We also provide in-depth knowledge about why this ultra tough material is the ultimate option for all your industrial needs.
Why Urethane Sheets?
Urethane flat sheet stock has the ability to provide reliable performance and endure all kinds factors in different applications. It is one of the most preferred materials in a variety of industries. This is especially true for standard-cast polyurethane sheets, which can be used as media blast material, as well as chute liners, protective covers, and forming pads.
The Importance of Urethane Sheets in Manufacturing
Urethane characteristics are extremely versatile so this elastomer is used throughout the world in all kinds of industries for a variety of applications. There are many advantages polyurethane has over other materials; it is tougher, stronger, more adaptable, and more durable. It can provide better value compared to parts made from other materials which will often break, crack, swell, tear, and deteriorate.
Urethane as a Material
Urethane boasts a higher load-bearing capacity and can withstand a tremendous temperature range without becoming brittle or cracking. As a result, this impressive elastomer has resistance to many environmental hazards, including:
- Oxygen and ozone attacks
Polyurethane sheets have many chemical compounds and can boast up to ten times higher abrasion resistance compared to other elastomers. It can even provide long-term water stability. As an abrasion-resistant material, it has excellent tear and tensile strength, plus a higher load-bearing capacity. Polyurethane sheeting is the ideal choice for a wide array of tough applications.
Depending on the usage, polyurethane flat sheet stock can be a better choice than metals because it’s a very resistant to wear. Its higher load-bearing capacity can be measured in tension, compression, and shear, where it can be made into polyurethane components that are thinner, lighter, and more durable. Because of these unique properties, the machinability of hard urethane is similar to both metals and plastics.
A Brief History of Urethane
Polyurethanes were first created in 1937 when Friedrich Bayer, a German chemist, developed Perlon U. It is known as the earliest prototype of the polyurethane polymer. It wasn’t until three years later in 1940 that the first successfully developed polyurethane elastomers appeared. Polyurethane elastomers had similar physical properties to rubber so they were often used as a replacement in many applications during World War II.
Later on, scientists discovered that synthesizing polyurethane and combining it with nylon resulted in a stretchable and lightweight material. In 1953, polyurethane foam was first commercially produced in the U.S. It was rigid and could be ideally used as insulation – although this changed when a cheaper and more flexible variant was introduced in 1956.
During the late 1950s, polyurethanes began to be used as adhesives and moldable urethanes were developed. This moldable material with elastic memory allowed for even more applications, which included flexible cushions. Today, development in polyurethane has been further refined to create more materials, including:
- Polyurethane coating
- Spandex fibers
There are many reasons why polyurethane sheets are the go-to option in various industries. Urethane characteristics are almost boundless; below are the specifications for this highly versatile material.
When considering the hardness and range of production behind urethane, it is one of the most versatile materials available. This material has a durometer measurement that can range from as hard as a bowling ball to as soft as a marshmallow. Many polyurethane flat sheet stocks can be graded across three different durometer standard stock sizes and can offer a full range of hardness, which can be seen below:
- Shore OO: This scale is used to measure very soft materials.
- Shore A: This scale is used to measure rubber as well as many other elastomers; it is the most common scale.
- Shore D: This scale is used to measure harder materials such as rigid plastics.
With this scale in mind, you should also remember that a durometer standard stock size is only a general indicator of a material’s physical properties, but it won’t be able to accurately assess just how versatile urethane is. If you’re not looking for a certain hardness, you can look into other tools for measuring other properties, such as:
- Temperature resistance
- Flex strength
- Water / chemical resistance
- Superior impact resistance
The durometer standard stock size is one of the most readily available metrics, but not the only one to consider when looking into polyurethane products.
Formulations and Their Effects
Polyurethanes are the result of a chemical reaction between an isocyanate and a polyol, creating a pre-polymer. This is then cross-linked to a curative, forming the polyurethane – this may seem like a simple and straightforward chemical formula, but there is a lot of room for variability and more complex results.
For example, thermoset polyurethanes are typically made up of Toluene Diisocyanate (TDI) and Methylendiphenyl Diisocyanate (MDI). These are chemicals used to make many household products and offer good properties at both low and high temperatures.
Each of these unique combinations will create different chemical bonds and can result in different physical properties in the material. Moreover, there are many chemicals that can be added as curatives for polyurethanes, which opens up the possibility of creating something completely new.
With this many factors involved, it’s not hard to come up with an endless variety of combinations and formulations just by making small adjustments to the base formula. This is why product teams and engineers need to evaluate all of their urethane products and avoid choosing results according to just one or two criteria. Throughout the product development process, it’s imperative for creators to take the urethane formulation into account.
Chemical Resistance and Interaction with Oils, Hydrocarbons, and Solvents
Urethane is inherently oil resistant and solvent resistant, meaning anything made from polyurethane components will do well when used in applications that expose it to oil and fuel. One thing that can considerably influence urethane chemical resistance is the chemicals used to make it. As such, it is highly critical to understand these essential pieces of information about the environment and stresses that the product will be put under.
Knowing this ahead of time will ensure that users will have the right kind of formulation in the urethane they’re interested in and that it can answer their needs. Apart from chemicals, urethane’s resistance to various solvents can be affected by the duration of contact with the substance, different temperatures, and even the concentration of the substance.
When it comes to water, oil, and grease, urethane’s material properties can stay stable, with only a small amount of swelling in some cases. Furthermore, urethane can hold up its form against a wide range of chemicals, and is also solvent resistant, provided that the chemicals’ pH levels aren’t too basic or too acidic. Urethane components are most resistant to neutral pH levels.
Urethane in Manufacturing
You may already know how often urethane is used in manufacturing, but knowing further details can help you determine why it is the preferred choice. Below are just a few of the most common industries where you will see polyurethane flat sheet stocks in action.
Polyurethane sheets are an elastomeric material that come in varying colors and hardness ranges, with a standard size of up to around 6 inches thick. Variations in both the physical and mechanical properties can range from a rigid, high-density sheet – this will have a durometer measure of Shore D – to something that’s much softer. Because of their hardness and abrasion-resistant properties, polyurethane sheets will generally perform better against metal, plastic, and rubber components.
Moreover, polyurethane is known to handle fatigue well and has an excellent load-bearing capacity, is cut resistance, and has resistance to other environmental factors. The elastomeric composition of polyurethane flat sheet stock can be both flexible and rigid so it is commonly used in construction, where its resistance to the environment is heavily advantageous for wear resistance. Polyurethane sheets can be also combined with cast-in reinforcement materials, such as glass, graphite, and fiberglass for more applications.
Common Elastomer Applications
#1. Material Handling
Provides longevity in applications such as chute liners, hopper liners, and concrete forms.
#2. Metal Forming
Provides elastic strength and protection against compressive forces that are incurred during metal stamping and metal processing.
#3. Grain Handling
Used extensively in the agriculture industry as liners for grain bins, hoppers, elevator buckets, valves, and chutes.
Provides excellent wear resistance against abrasive media such as sand, rocks, concrete, and ore. Generally used as a liner to protect metal components.
Other Non-Elastomer Applications
Rigid, low-density polyurethane has a wide range of uses, with the biggest one being in applications for thermal insulation. When a building is constructed, it is imperative to insulate the walls with low-density rigid polyurethane flat sheet stock to significantly reduce cooling and heating bills. This is possible because polyurethane sheets can keep the heat in during winter and out during the summer.
As a result, you will be able to cut carbon emissions from your home or commercial property while helping to limit the negative impact that expending energy will have on the planet. Furthermore, polyurethane flat sheet stock has a life span of more than five decades and won’t need any maintenance. As such, it is the ideal choice of material for those looking to build a new construction.
Polyurethane sheets and products can be molded into foam that can be used in a wide variety of furniture. This kind of foam comes in different qualities, durability levels, firmnesses, and densities. Those with higher quality and density will often result in a higher price (usually sold per sheet by the quarter-inch).
Softer and more temporary foams are used more often for short-term pieces like those in baby mattresses. On the other hand, luxurious, top-of-the-line polyurethane sheets will usually be reserved for things like bay window cushions. Finally, the fabric found in standard car seats will often be made from polyurethane, because it is both durable and comfortable.
Advantages Over Other Materials
There are plenty of reasons why many people prefer polyurethane flat sheet stock over other materials. Here are just a few:
Very broad hardness range
Polyurethane products have a very broad hardness range based on the pre-polymers’ chemical and molecular structure. As a result, their hardnesses can range from anywhere between 20 Shore A to 85 Shore D.
Polyurethane sheeting can be very flexible and is the preferred choice for various applications. It has good recovery and elongation properties.
High load-bearing capacity
Because polyurethane can carry heavy loads in terms of both compression and tension, it can be used in all kinds of applications. While it may change in shape under huge loads, its elastic memory means it will always go back to its original shape once the load is removed.
Superior impact resistance
Polyurethane is an ideal solution in challenging projects because of its high tensile properties and high tear resistance.
Oil, grease, and water resistance
Polyurethane sheet can potentially last for many years when applied in subsea environments. Its properties also allow it to remain stable in oil, grease, and water with minimal swelling.
Wide resiliency range
Because it can be created to become hard, urethane products have high resiliency and may be a good electric insulation choice. If you’re looking for shock absorption, look for low rebound compounds with a resilience range between 10% to 40%. If you need quick recovery with your polyurethane flat sheet stock, look for high-frequency vibrations in compounds with a resilience range between 40% to 65%.
Mold, fungus, and mildew resilience
Many polymer-based polyurethanes don’t allow for growth of any kind, whether it’s fungal, mold, or mildew. This material is highly suitable for tropical environments. Furthermore, special additives can be added to improve resilience in polyurethane flat sheet stock and other related materials.
Strong bonding properties
These sheets can bond to many kinds of materials during the manufacturing process, including metals, wood, and other plastics. Polyurethane is the ideal partner for rollers, wheels, and inserts.
Great performance in harsh environments
Urethane products are highly resistant to extreme temperatures, including all kinds of tough environmental conditions. This is due to the chemicals used in their creation, which rarely cause degradation in the material.
Short production times
When compared to traditional thermoplastic materials, the urethane flat sheet stock option has a shorter lead time. It also has lower production costs compared to traditional materials when custom sheet sizes, colors, and durometers are required.
When compared to other parts made from plastic, urethane parts will have a somewhat similar cost. However, making the casts for urethane products will cost less, since most casts will be made out of affordable metal. Other sheet extrusion methods may provide cost savings in mass but they require larger scale production volumes and do not provide the same physical properties as hot cast urethanes. In the long run, cast urethane sheet is more cost-effective than extruded urethane sheet because it will provide better physical properties and custom, low waste production.
Metal, another polyurethane competitor, is more expensive to manufacture. Casting metal cannot be done without the use of heavy-duty machines and welding processes. These extra steps aren’t needed for casting urethanes, which is much more straightforward.
When compared to rubber, polyurethane has higher material costs, but is less expensive to manufacture. At the point of purchase, polyurethane will cost slightly more than both synthetic and natural rubber. Be that as it may, polyurethane usually lasts longer than rubber materials.
Polyurethane flat sheet stock is among some of the most powerful, flexible, and versatile material available on the market today. It has useful chemical properties, it can be as soft or as hard as needed, it is abrasion resistant, oil resistant, and solvent resistant, and it can be used in many different projects, both industrial and residential. Additionally, the base formulation for the urethane flat sheet stock can be easily changed to serve any purpose the manufacturer needs and as a result, it has a near-infinite variety of combinations.
No matter what kind of application you wish to use your polyurethane sheeting for, you can be sure that you’re in good hands with Uniflex. Please give us a call at 248-486-6000 or contact us online directly through our website. We have experienced staff eager to help you plan out your next project and get the materials and parts you need!