Plastics are used globally for outdoor and indoor products, especially those found in our offices, households, and industries. However, products designed for outdoor use are typically exposed to ultraviolet (UV) radiation from the sun.
As such, it is important that the type of plastics used for outdoor applications can withstand UV radiation. The radiation shortens the lifespan of your plastic products and causes degradation.
UV-resistant plastics can absorb the sun’s radiation without corrosion. Although no plastic is completely UV-resistant, some materials do a better job of resisting the sun’s harmful rays.
This article highlights the top 8 UV-resistant plastics that are excellent for outdoor use and information to help you understand how UV radiation affects plastics. So, keep on reading for our top recommendations.
What Are UV-Resistant Plastics Made of?
Before you can choose the best UV-resistant plastic for your outdoor applications, it’s essential to understand the components of the materials.
So, first off, what does UV-resistant mean? Well, UV-resistant simply means the ability to resist the damaging effect of the sun’s ultraviolet rays.
Plastics are either made from UV-resistant components or made UV-resistant by using additives. For example, certain plastics such as acrylic, PTFE, and PVDF have high UV resistance in their natural state, while non-UV-resistant plastics require additives such as UV stabilizers, protective surface coatings, or black coloration.
Top 8 UV-Resistant Plastics for Injection Molding
Injection molding is a widely-used manufacturing process with a host of applications. For making outdoor products, you must use UV-resistant plastics. There are different types of plastic, and they all have different levels of UV resistance.
Here’s a list of the top 8 UV-resistant plastics that are perfect for the injection molding process:
Acrylic is one of the most used plastic materials for outdoor applications. Acrylic is UV-resistant and only suffers a 3% degradation over a decade. It is a popular choice because it is a clear plastic, and it is scratch resistant.
Acrylic is also known as Polymethyl methacrylate (PMMA) or “plexiglass.” Acrylic UV-resistant is not only resistant but also very durable and has high rigidity. This is why it is ideal for long-term use.
Additionally, acrylic has a variety of outdoor applications.
For example, it is used for outdoor signs and displays, colored lenses, light fixtures, reflectors, and decorative panels. Acrylic is an excellent choice if your applications don’t involve high pressure or heavy impact.
Nylon is a thermoplastic that is usually made from petroleum. This silk-like material is one of the most useful UV-resistant plastics with many applications in daily life and industries. It is highly resistant to wear, heat, and chemicals.
Thanks to its physical and chemical properties, nylon can be processed into fibers, films, shapes, filaments, fabrics, parachutes, etc.
Additionally, nylon is used in injection molding. Nylon polymers can also be mixed with various additives for different variations and to improve UV resistance.
Another excellent UV-resistant plastic you can consider using is polycarbonate. It is durable, impact-resistant, and has similar transparency as acrylic. More so, polycarbonate is 200 times stronger than glass. So, it is suitable for extreme temperature applications.
Polycarbonate is a common material for heavy-duty products such as goggles, shields, helmets, and so on. It is also used in the medical field to make syringes, surgical instruments, drug delivery systems, etc.
Despite polycarbonate’s UV resistance and other wonderful attributes, it is more expensive than other types of plastic on our list, including acrylic. However, polycarbonate is worth the price tag.
Polytetrafluoroethylene (PTFE) is another top-rated plastic material made from carbon and fluorine atoms in the manufacturing industry. PTFE exhibits high UV resistance to light and is resistant to extreme weather conditions.
Additionally, this plastic is flexible and has low water absorption, remarkable anti-adhesion properties, and low dielectric constant.
PTFE is extensively used in various electrical, medical, chemical, and engineering industries. It is used to manufacture bearings, fittings, pumps, valve & pump parts, non-stick surfaces, containers, electrical insulation, shaft seals, gaskets, and so on.
Furthermore, PTFE is an inexpensive plastic. Apart from its UV resistance, it is also a top choice thanks to its non-stick properties. PTFE has one of the lowest coefficients of friction against any solid.
HDPE, or High-density polyethylene, is a thermoplastic from the ethylene family which is made from petroleum. Just like nylon and acrylic, HDPE is a commonly used plastic globally. It is a popular choice because of its durability, but it can easily be molded into various shapes or products.
HDPE is inexpensive and has high UV resistance. This is another reason why many manufacturers prefer plastic for making products like playground equipment, containers, plastic toys, pipes, drums, dust bins, food packaging, outdoor furniture, and open-air infrastructure.
Lastly, HDPE is not the best for high-pressure applications because it is more impact resistant than other plastics.
Polyetherimide, also known as PEI, is another plastic whose high level of UV resistance has made it a popular choice for industrial, mechanical, and chemical applications. PEI is remarkably strong and flexible and exhibits chemical stability when exposed to acids and heat resistance.
Furthermore, PEI is usually manufactured in two forms; transparent and translucent. Its most common applications are in the industrial, mechanical, automotive, and medical industries.
PEI is perfect for heavy-duty applications involving extreme temperatures and pressure exposure. It is used to manufacture electrical parts, heat shields, heat sensors, small engine parts, and automobile and aviation components.
7. Polyphenylene Sulfide
Polyphenylene sulfide, or PPS, is a high-temperature UV-resistant plastic used in construction and molding for its opacity and rigidness. This semi-crystalline material has a high melting point of 280C. Additionally, PPS has high fire and heat resistance.
This plastic has outstanding chemical stability, durability, and good electrical insulating properties. PPS is limited to darker colors because of its crystalline structure.
Furthermore, It has several applications, including medical and healthcare, appliances, industrial, automotive, electronics, and electrical. PPS is used for products like coolant systems, bulb housing, switches, electric brakes, water pump impellers, and more.
8. Polyvinylidene Fluoride
Polyvinylidene fluoride, or PVDF, is a plastic material that is becoming increasingly popular in manufacturing for all the right reasons. Apart from PVDF’s UV resistance, it also has excellent chemical resistance and the strongest piezoelectric properties.
However, PVDF is an expensive plastic material. That’s why manufacturers usually combine the top-notch plastic with cheaper ones or use it as a coating to improve metals’ resistance to weather and chemical exposure.
There are two forms of PVDF: homopolymer PVDF and copolymer PVDF. Both forms boast strength, high heat deflection, impact resistance, and the ability to maintain shape.
PVDF is used to make valve parts, piping, gaskets, seals, fittings, chemical tank liners, semiconductor equipment, and so on.
Improving UV Resistance
Certain plastics that you may come across are not as naturally resistant to UV as others. Likewise, the plastics covered in this article all have different levels of UV resistance.
However, you can improve the UV resistance of these plastics that are not naturally UV-resistant. All you need to do is add UV-resistant additives or caps to protect the base polymer.
Caps or protective seals can significantly reduce the photodegradation rate of the plastic and preserve its appearance over time.
There are three major categories of UV-resistant additives. These are:
Blockers basically provide plastics with a protective layer that blocks the effect of UV light. Some of the most common blockers you can use include titanium dioxide and carbon black pigments. Carbon black is a blocker used for outdoor applications to block UV rays from degrading the plastic’s polymers. Another excellent blocker is titanium dioxide.
Absorbers are organic compounds that absorb UV light and convert it to heat instead. Benzophenones and benzotriazoles are popular absorbers used in manufacturing. Benzotriazoles can be combined with plastic in small concentrations to boost UV resistance.
Also, benzotriazoles are often combined with polycarbonate and acrylic for transparency. In comparison, benzophenones are frequently combined with polyvinyl chloride (PVC) and polyolefins.
Stabilizers work by maintaining the chemical integrity of the plastics. Using chemical techniques, they prevent a polymer’s bonds from rupturing and trapping free radicals.
The chemicals of stabilizers reduce the UV levels the plastic material is exposed to until it is non-harmful.
Additionally, stabilizers can effectively isolate and collect any free radicals. One of the most common stabilizers used is Hindered Amine Light Stabilizers (HALS). If HALS is compatible with the plastic you’re working with, it will significantly boost the performance of your material.
Which Plastics Are Resistant to UV Radiation?
As we mentioned earlier, not every plastic is resistant to UV radiation. Even among those who can resist the sun’s radiation, some do a better job than others. Nylon and polypropylene are not typically categorized as UV-resistant plastic. The main categories of UV-resistant plastic materials are:
Fluoropolymers are materials with natural resistance to UV radiation. These plastics have good resistance thanks to their strong carbon-fluorine bonds that prevent degradation. Examples of fluoropolymers include Polytetrafluoroethylene (PTFE), Polyvinylidene fluoride (PVDF), and Fluorinated Ethylene Propylene.
Imides are more outstanding than fluoropolymers at resisting UV radiation. They are highly UV-resistant plastics that are usually used in applications that involve exposure to high levels of UV radiation. The most common imides used in construction are Polyimide (PI) and Polyetherimide (PEI).
Choosing a Material
Before you choose a type of plastic, there are many factors you need to consider. Some of these factors include:
- Friction resistance.
- Temperature resistance.
- Chemical stability.
What Factors Matter in UV-Resistant Plastics Selection
Selecting a UV-resistant plastic that’s perfect for a project requires that you consider certain factors before making your choice. Some of the important factors you need to consider include the following:
1. Mechanical Requirements
The mechanical requirements for your project are crucial in determining the type of UV-resistant plastic you choose.
The strength, flexibility, temperature resistance, and stiffness are some attributes you need to look out for. If the plastic meets your mechanical requirements, you’ll have no issues.
Additionally, the plastic you want to use must be compatible with the type of application you intend to use.
For example, the plastic should be perfect for processes like injection molding, extrusion, or blow molding. When the plastic checks this box, you’ll have no issue molding the plastic into your desired shape and size.
2. Chemical Compatibility
Apart from being excellent UV-resistant, the plastic you want to use should have chemical compatibility with other materials you will use in your project. The longevity of your product depends on the ability of the plastic to resist chemicals, water, and UV radiation.
For example, when manufacturing a product like a chemical storage tank, you would need to use a plastic material that is compatible with the chemicals that will be stored. Some plastics that are ideal for this kind of scenario are polypropylene or PVC.
Furthermore, plastics have varying chemical compositions and properties such as melting points, viscosities, opacity, etc.
These factors affect the way plastic can be used to create other products because you’ll need to consider the temperature and pressure needed to turn the raw plastic into a finished product.
3. Environmental Compatibility
It is very important for you to consider the environmental impact of the plastic material you want to use. You must only use environmentally friendly plastic. The plastic needs to be biodegradable to ensure its use or disposal doesn’t negatively impact the ecosystem.
Single-use plastics are known environmental pollutants.
However, it is possible to limit or reduce the environmental impact by recycling or reusing plastics. This means you should opt for reusable and recyclable plastics that are more environmentally friendly.
The weight of the plastic is another significant factor to consider. Depending on the application, you may need a heavy plastic that can absorb pressure without breaking or bending or something more lightweight. For example, HDPE is just the right weight to make plastic toys, containers, park benches, and so on.
5. Material Cost
The best plastic material for your project must be cost-effective. This means you have to select one with the required attributes, and it doesn’t cost beyond your budget.
For example, polyethylene is inexpensive, available, and durable, while polycarbonate is more expensive thanks to its special properties, application, and production processes.
Additionally, the processing cost of plastic can increase its price. For example, some plastic can only be processed with special equipment or expensive methods.
While some plastic products can be made from processes like injection molding, others may require something more complicated and expensive.
Kemal: Plastic Injection Molding Services
Kemal is a leading company in the manufacturing industry with over 30 years of experience conducting top-notch services for customers.
Kemal is your best option if you’re in the market for a top-tier UV-resistant plastic supplier for multiple types of UV-resistant plastics. Regardless of the application, Kemal’s products are reliable, durable, and cost-efficient.
Injection molding is a widely used plastic manufacturing process. Plastic pellets are melted and injected into a mold to form a shape. Plastic injection molding is used for various applications, such as creating children’s toys and large vehicle parts.
In terms of plastic injection molding, Kemal is the perfect choice to handle your prototyping needs and quick-turn plastic production. The company provides top-tier injection molded parts at a fair price with minimum lead time.
Kemal boasts state-of-the-art manufacturing facilities with accurate machines that ensure you get consistent products from the same mold.
More so, the company provides a fast quotation service that provides customers with free injection molding quotes after uploading their designs.
You also get design feedback from experts in the business for every order you place. These experts provide helpful tips on mold design, surface finishes selection, and the ideal shipping methods.