TAGS: 3D Printing Part Design & Manufacturing
The additive manufacturing industry is a fairly new and developing industry that started in the early 1980s. Since its invention, technology has improved significantly.
Recent developments in additive manufacturing have unlocked a significant potential for expanding simple ideas into complicated multimaterial geometries. New applications in biomedical devices, dentistry, medication delivery, microfluidics, rapid prototyping, tooling, tissue engineering, etc. have all been made possible by the advancement of 3D printing technologies.
Vat photopolymerization is a branch of additive manufacturing that has a number of desirable characteristics, such as:
- outstanding printing resolution,
- high dimensional precision,
- low manufacturing costs, and
- the capacity to spatially regulate material properties.
The photopolymerization-based process gives users flexibility and control over the final qualities of the 3D printed materials, including optical, chemical, and mechanical properties.
Cyclic Olefin Resin (COR), a relatively new vat polymerization printing material, is an engineered material that addresses some of the challenges of conventional 3D printing resins. This material:
- brings durability, chemical resistance, and temperature stability to 3D printing, and
- shows a lot of potential in the future of additive manufacturing.
Let's take a look at the features and uses of cyclic olefin resins (COR) in additive manufacturing versus other conventional resins.
Basics of Photopolymers and Additive Manufacturing
A photopolymer, or light-activated resin, is a substance whose characteristics change when it is exposed to light. In the 3D printing field, photopolymerization printers use these photopolymers as printing materials by taking advantage of their UV sensitivity and using it to selectively cure resin into a 3D printed design. A process known as
photopolymerization causes the molecules of liquid photopolymers to quickly link together and cure into a solid state when exposed to particular wavelengths of light.
3D printers usually use
UV light to cure the resin. These UV rays set off a reaction and modify the structure of the photopolymers, changing their chemical and mechanical properties.
The build platform is partially submerged at the liquid's surface in the majority of 3D printers that employ vat photopolymerization. The printer manages a light source that is used to selectively cure the photopolymer into solid layers using information from a CAD file. After a layer is cured, the build platform usually moves downward by the thickness of one layer. The process is then repeated for the successive layers until the full design is produced.
Due to their advantages over other 3D printing materials,
photopolymers are a common material for 3D printing. Additionally, photopolymers are incredibly adaptable and can be utilized to produce items with properties that correspond to a variety of requirements, including:
- transparency,
- flexibility, and
- strength.
This innovative material allows engineers to create better items with more attractive features.
Advantages of Photopolymerization-based 3D Printing
Even though extrusion-based 3D printing techniques might be the most popular among consumers,
photopolymerization-based 3D printing features following number of benefits.
- Photopolymerization-based 3D printing has the capacity to create components with a variety of mechanical and optical characteristics. This capability arises from the fact that the final qualities of the part are influenced by the monomers and oligomers selected for the photopolymerization process. The variety of monomers used also allows engineers to adjust the resulting part's transparency. Due to this characteristic, photopolymerization-based 3D printing is a desirable choice for applications that call for parts with particular mechanical or optical characteristics.
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Users can also design and produce delicate designs or intricately shaped objects using photopolymerization-based 3D printing. This technology boasts precision, high detail, and superior-quality prints with a smoother surface finish. The printing process is also faster than some of the other 3D printing technologies.
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Photopolymerization-based 3D printing is a good option for applications requiring complicated structures, such as mechanical components with numerous moving parts. It is also ideal for medical implants.
Disadvantages of Vat Polymerization
Though photopolymers have many benefits, they do have some challenges. Some of the drawbacks of vat polymerization include:
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It is expensive compared to other 3D printing technologies.
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Lack of options for photo-resin materials.
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Inadequate durability and strength.
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Resins can still be impacted by UV light after printing.
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Over time, resins may distort and flex.
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To acquire substantial strength, printed items often need to be post-cured for a long time.
What is Cyclic Olefin Resin?
A recent advancement that engineers have made in vat photopolymerization includes the development of a rugged material called COR (Cyclic Olefin Resin). COR is a type of photopolymer that enables many of the properties of Cyclic Olefin Polymers (COPs) — a type of thermoplastic — to now be accessible in photopolymer resin form.
Traditionally, COPs were engineered thermoplastics used in a variety of applications including packaging, medical equipment, optics, and toners.
Existing research demonstrates that COPs have the following features:
Additionally, COPs are well suited for injection molding due to their high degree of purity, low moisture absorption, and negligible warpage.
Cyclic Olefin Resins
Engineers have been working on advancing the material range for 3D printers. COR, being a photopolymer, is one of the materials that have favorable characteristics for the additive manufacturing industry. To reduce the failure risk of conventional materials and to provide durability to fend off part breakage, engineers have created a tough COR material for 3D printing parts. This revolutionary
3D-printed polymer has:
- High durability and can withstand high temperatures.
- It also has enhanced impact strength (comparable to injection-molded materials and metal).
- it has good chemical resistance to solvents and chemicals, including water, acetone, isopropanol, and other polar fluids.
Advantages, Disadvantages, And Limitations of COR
Advantages of Using COR
Cyclic Olefin Resins are incredibly tough and rugged, making them suitable for harsh applications in which high-impact strength is required. This, combined with its low density, makes COR ideal for lightweight, high-stress applications, such as in the automotive industry.
The temperature sensitivity of traditional photopolymer resins is also addressed with CORs. Cyclic Olefin Resins keep their characteristics at high temperatures, whereas other 3D-printed photopolymer resin parts would deteriorate and fail.
This combination of high-impact strength and high-temperature tolerance is unique in the world of photopolymer resins for additive manufacturing.
Other advantages of COR include its high chemical resistance, higher glass transition temperature, and the level of detail achievable by using a photopolymer resin for 3D printing.
Disadvantages & Limitations of Using COR
Traditional photopolymer resins suffer from two main following drawbacks namely:
- impact strength and
- temperature sensitivity.
Both of these drawbacks make many photopolymer 3D printing resins unsuitable for commercial and industrial use.
Like all things, there are some limitations to using COR for additive manufacturing. Being a fairly new technology, specialized DLP 3D printers are required to work with CORs. There are also a limited number of color options available currently, including Amber and Black, which can be overcome through the use of coatings.
Uses of Cyclic Olefin Resin (COR)
The unique combination of properties of CORs makes them suitable for high mechanical stress, high temperature, and lightweight applications. Being a photopolymer resin, it is possible to create complex parts with incredible detail.
Automotive Industry
The automotive industry is an ideal example of where COR is uniquely suitable. Parts need to be rugged to withstand the high stresses that a vehicle undergoes, while also being lightweight in order to increase performance and fuel efficiency. A tough, lightweight photopolymer resin such as COR could be used in parts ranging from manifolds to connector housings.
Aerospace Industry
Similarly, the aerospace industry requires parts in which every ounce matters, and where you cannot afford failure. The incredible strength-to-weight ratio of COR, along with its ability to withstand high temperatures make it ideal for use.
Highly detailed parts can be precisely engineered for unique applications in these industries, with the repeatability, ease of production, and cost savings associated with additive manufacturing.
Electronics Industry & Others
COR is suitable for use as connectors, casings, or any other non-conductive part in electronics. Its chemical resistance also makes CORs suitable for use in fluid handling, including circumstances when the printed resin would be in contact with polar fluids. COR is ideal for any other applications in which lightweight, tough, precision-engineered parts are required.
Material Advancements in Additive Manufacturing
The use of CORs in additive manufacturing opens up a world of possibilities. The weaknesses of traditional photopolymer resins made them unsuitable for many industrial applications. Modern Cyclic Olefin Resins have addressed these shortcomings. The ability to 3D print components which are rugged, lightweight, and stable at high temperatures is invaluable for a wide variety of applications and industries.
3D Printing / Additive Manufacturing Using Polymers - Complete Guide