Composites Known for Their Insulating Properties

Composites Known for Their Insulating Properties

Insulation plays a significant role in many industries and applications, allowing for the safe use of electrical equipment and protecting users from heat transfer. Manufacturers in many spheres, from automotive to defense and power generation, rely on composite insulation material due to its unique properties.

Many consider polymers the ideal matrix because of their low cost, excellent electrical insulation, and processability. Understanding the properties of various thermoset composites is essential to selecting the most appropriate option for your application.

Is Plastic an Insulator? 

An insulator is a material that obstructs energy from transferring through a surface itself, typically via heat or electricity. Plastic is an excellent insulator as it does not significantly conduct heat or electricity. Polymers — long repeating chains of macromolecules — are tightly bound in a way that makes electrical or thermal energy transfer difficult. Two types of insulation exist:

  • Electrical insulation: This type prohibits electrons from flowing to or through a material. 
  • Thermal insulation: Although the process is similar, thermal insulation reduces heat transfer to or through a material, by making the chemical structure resistant to molecular movement.

Understanding how plastic insulates electric currents means exploring the concept of dielectric strength. It determines an insulating material’s resistance to electrical breakdown. Different materials have different dielectric strengths, and selecting the best option for your application is critical.

The Applications of Insulating Composites

Polymeric insulators have become an increasingly attractive alternative to traditional ceramic insulation. From plastic insulation sheeting to insulated composite panels and a range of other shapes, some typical applications of insulating composites include: 

  • Building and construction: Insulating composites are popular in insulation boards and panels to boost energy efficiency in residences and commercial buildings. 
  • Automotive: Custom plastic and composite parts have a high strength-to-weight ratio, improving vehicle safety and fuel efficiency. They also reduce ownership costs and increase component longevity thanks to factors like corrosion and impact resistance.
  • Industrial equipment: Insulating composites prevent heat loss, improve energy efficiency, and boost worker safety in many industrial environments.
  • Electrical and electronic devices: Composites with high dielectric strength are crucial in insulating materials for transformers, motors, circuit boards, and other electrical components. They meet the rigorous demands of semiconductor manufacturing, providing longevity, strength, corrosion resistance, and durability.
  • Aerospace and defense: The high temperature and high-pressure processes behind thermoset composite production set their chemical and physical properties, making them ideal for demanding environments.
  • Renewable energy: Composite insulation improves energy conversion efficiency and thermal management in alternative energy sources like wind turbines and solar panels.

Types of Composite Insulation Material

While composite materials have excellent insulation capabilities, each contains different materials that determine its degree of insulation under various circumstances. Some of the most effective composite insulation materials include:

Phenolic Composite

Phenolic materials are produced by applying heat or pressure to fabrics imbued with synthetic resin to create a dense, durable end product. These materials are popular in electrical applications due to their high dielectric strength and resistance. Their non-conductive nature and high electrical resistance make them invaluable in many industries.

Three main types of phenolic exist: 

  • Paper-based: This cost-effective option has good electrical insulating and mechanical properties. 
  • Cloth-based: This kind of phenolic is made from a combination of resin and linen or cotton canvas.
  • Glass-based: This option offers the best electrical properties, mechanical strength, and heat resistance.

Glass Epoxy

Expoxy resins are some of the most popular insulating materials, as their insulation properties are closely related to the safety of electronic transmission systems. This specific material comprises an epoxy resin and a glass-fiber matrix, ideal for low- to ultra-high-voltage distribution networks and high-energy electrical devices.

Each of the different types is suited to specific applications. Some of the most common insulation options include:

  • FR-4: This superior general material provides cost-effective electrical and mechanical strength and is often used for insulation in humid and dry conditions. 
  • FR-5: This material can keep its insulating and mechanical properties in an operating environment of up to 180 degrees Celsius (356 degrees Fahrenheit). Many automobile manufacturers prefer this material due to its ability to resist the spread of flames.
  • G-10: With excellent insulation and mechanical strength in wet and dry conditions, G-10 is ideal for electrical components and insulation.
  • G-11: This option has even better insulation properties than G-10 in wet and dry conditions. It also resists dimensional change, flow, and chemicals. 

Glass Polyester

Glass polyester is a cost-effective material with many insulative benefits. It’s constructed from fiberglass-reinforced polyester to provide self-extinguishing, low conductivity, and good mechanical strength. Depending on your application, you can choose from three main types, each with a different level of heat resistance:

  • GPO-1: This option is ideal for applications requiring strong electrical properties without excessive heat exposure.
  • GPO-2: The second glass polyester has good electrical properties, heat resistance, and flame and arc resistance.
  • GPO-3: This material’s insulative properties make it a popular choice for electrical components due to its insulation and chemical resistance.

Glass Silicone

Glass silicone has excellent arc resistance and high heat resistance, excelling when used in electrical, electronic, and mechanical operations, especially when the material must withstand extreme temperatures. Glass silicone G-7 has better strength in high temperatures than many other composite materials and works well in wet and dry conditions.

Glass Melamine

Melamine is a compound used in plastic production known for its alkali resistance and excellent insulative properties. G-9 glass melamine is made from a continuous filament glass cloth and a melamine resin binder, creating a hard material that maintains its insulative strength even in humid conditions.

It can also withstand temperatures up to 140 degrees Celsius (284 degrees Fahrenheit). This composite excels in applications like circuit breaker components, architectural insulation, switchboard panels, and switch mounts.

The Benefits of Composite Insulation Material

Among other applications requiring insulation, power equipment such as cables and transformers are directly affected by the performance of their insulating materials. Whether you’re looking for electrical or thermal insulation, thermoset composite materials offer considerable benefits:

  • Low maintenance: Composites are not prone to corrosion, resulting in less frequent repairs and maintenance.
  • Design flexibility: Thermoset composites give designers almost unlimited flexibility in complex shape and form design. Manufacturers can produce them in various densities and chemical formulations to suit many unique applications.
  • Excellent strength: Reinforced composites outperform most metals in strength and strength-to-weight ratio.
  • Energy efficiency: Insulating composites reduce energy consumption and lower heating and cooling costs in various applications, from residential construction to large-scale industrial operations.
  • Lower long-term costs: Although thermoset composites represent a higher upfront investment than metals, their ability to combine properties like insulation, mechanical strength, and weight and resist corrosion represents significant long-term savings. 
  • Elevated safety: Thermoset composites are a safe and reliable method of protecting workers and end users. Their fire resistance, thermal protection, and electrical insulation are the best options for maintaining safety in multiple industries.

Contact Atlas Fibre for Composite Insulation Material Today

Insulation is one of the most critical properties of many materials, and thermoset composites combine excellent electric and thermal insulation with various other properties to create a dynamic, cost, and energy-efficient solution for many industries.

Atlas Fibre has the largest stock of thermoset materials in North America. Whether you need thermal or electrical insulation, flame, and arc resistance, or a high strength-to-weight ratio, we can match the right composite material to your unique needs. 

Contact us today to learn more about how Atlas Fibre makes composites possible.

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