Silicone or Neoprene: Which is better

As two similar types of synthetic rubber, silicone and neoprene are widely used in industrial and consumer products, etc. But which material offers better value and is a better fit for your product? This article will show their characteristics, compare their differences, and provide application references. Start gathering information now to make a more informed decision!

What Is Silicone

Silicone is a special type of synthetic rubber whose molecular backbone is composed of silicon and oxygen atoms, giving it excellent stability. It is manufactured from quartz sand through processes such as heating, grinding, hydrolysis, condensation polymerization, and vulcanization.

Core Advantages

• Excellent biocompatibility
• Flexibility
• Wide temperature tolerance range
• electrical insulation

What Is Neoprene

Chloroprene rubber, CR, and polychloroprene all refer to Neoprene, a type of synthetic rubber. It is an elastomer derived from chloroprene and is widely used in industrial and other fields.

Core Advantages

• Oil and solvent resistant
• Excellent sealing performance
• High physical and mechanical strength

Similarities between Silicone and Neoprene

Silicone and neoprene are similar in many ways, which is why many people are confused when choosing between these two materials:

• Excellent weather resistance, including resistance to UV radiation, ozone, and weathering
• Frequently used in the manufacture of various sealing components, such as gaskets and O-rings
• Can be processed into different densities to provide shock absorption and noise reduction
• Good flame retardancy

The Differences between Silicone and Neoprene

In reality, they differ in many aspects, especially in terms of temperature adaptability, chemical compatibility, physical and mechanical strength, and biocompatibility. They differ in the following eight aspects:

Price

Silicone is more expensive than neoprene, especially those used in medical and food applications. To ensure safety, manufacturers often use higher-purity raw materials and safer additives.

Neoprene is often cheaper to meet the needs of large-scale industrial use and the demand for cost-effective materials.

Lifespan

The lifespan of silicone and neoprene is usually 10-20 years, but this figure is actually influenced by several factors. Extremely high or low temperatures, exposure to sunlight, continuous wear, and other factors can all shorten their lifespan.

The lifespan varies greatly among different types of silicone and neoprene. High-quality medical-grade silicone can still work properly after 30 years, while some silicone sponges only last for a short period of 5 years.

In short, their specific durability depends on what you intend to use them for and their type.

Temperature Range

Silicone can function normally between -60°F and 450°F, which is -50°C to 230°C. Phenyl silicone rubber is even more tolerant of environmental temperatures, able to withstand extreme low temperatures of -110°C and short-term temperatures of 300°C.

Even at such extreme temperatures, the properties of silicone itself change very little. It won’t melt within the specified temperature range and still maintains its flexibility. Because of these characteristics, silicone can be used in fields such as aerospace, providing reliable sealing even under conditions of significant temperature changes.

Neoprene has a much narrower temperature range, only -40°F to 230°F, or -40°C to 110°C. It can also withstand high temperatures of 121°C for short periods. Therefore, neoprene is more suitable for applications at regular temperatures. If your product is designed to work above 120°C, silicone rubber would be a better choice.

Physical Properties

Hardness

Silicone is softer than neoprene, with a hardness ranging from 25 to 80 Shore A. Neoprene has a hardness range of 40-90 Shore A. Because silicone is soft enough, it is ideal for making materials that conform to the body and skin, such as watch straps or baby pacifiers. The hardness of neoprene means it can provide better support, so it can be used to make rigid protective cases.

Tensile Strength

Neoprene can withstand greater tensile force than silicone, meaning it is less likely to break or suffer permanent structural damage, such as cracking due to external forces. But silicone is more flexible and can be stretched to seven times its original length.

Stress Resistance

Silicone and neoprene have similar compression set properties, but silicone has less deformation upon recovery than neoprene. Generally, both materials are enough for the needs, but if you require a material with long-term stable compression resistance, silicone would be a better choice.

Tear Resistance and Abrasion Resistance

Neoprene is more wear-resistant than silicone. In parts that are frequently subjected to friction, such as bearing pads, Neoprene can minimize the loss of precision due to wear after prolonged use and reduce the frequency of replacement.

What’s more, neoprene is less prone to cracking, which further enhances its durability.

Chemical Properties

Chemical Compatibility of Silicone

Silicone is chemically inert and, in most cases, doesn’t react with other substances, making it a safe and reliable sealing material. It can be in long-term contact with the following substances:

• Automotive brake fluid
• Water
• Ozone
• Fire-resistant hydraulic fluid
• High molecular weight chlorinated hydrocarbons
• Oils and fats
• Weak acids and weak bases

But silicone is not suitable for all applications. When silicone comes into contact with substances like fuel, these substances slowly permeate the three-dimensional network structure of the silicone molecules, causing it to swell and degrade. It is incompatible with these substances:

• Hydrocarbon fuels
• Strong bases and strong acids
• Aromatic hydrocarbons
• Trichloroethylene
• Steam above 121 °C
• Some solvents

Chemical Compatibility of Neoprene

Because neoprene was initially designed for better oil resistance, it can handle many tasks in industrial applications that silicone cannot, and it offers superior corrosion resistance. It can be used in products that come into contact with these chemicals:

• Solvents, such as methanol and ethanol
• Water
• Ozone
• Mineral acids
• Alkalis
• Refrigerants
• Weak acids
• Lubricating grease
• Silicone oil

And aeoprene performs poorly when exposed to these chemicals:

• Hydrocarbon fuels
• Aromatic hydrocarbons
• Concentrated acid
• Oxygen-containing solvents

Safety

As a material that has long been used in the medical and food production fields, silicone’s safety is widely recognized. Food-grade and medical silicone not only use pure raw materials and ensure hygienic production, but also have FDA standards as a baseline guarantee of quality.

Standard-compliant silicone is non-toxic and odorless, and can be used to produce various health products, even products that can be implanted into the human body. It does not contain plasticizers, heavy metal ions, BPA, PVC, or other chemicals that may be harmful to the human body or cause cancer.

Neoprene itself is non-toxic and will not cause any harmful effects if it only comes into contact with the skin, but it may cause some unexpected allergic reactions.

If you want to choose a safer and more trustworthy material for your products, silicone can meet your needs.

Air Permeability

Silicone is a highly breathable material, allowing gases to pass through the spaces between its molecules. Because of this property, it can be used in medical dressings to promote better wound healing.

Unlike silicone rubber, neoprene is not as flexible, but its dense structure gives it excellent sealing properties. This is an advantage when used in seals such as O-rings, but it can cause discomfort to users when used in athletic equipment.

Electrical Insulation

Although both are electrically insulating, silicone provides better electrical insulation than neoprene. Silicone has a very low dielectric constant, which means it can effectively prevent current leakage when used as a sealing material for electronic components.

By adding certain special components, silicone can also be made into conductive silicone rubber.

Are Silicone and Neoprene Eco-friendly?

In a sense, silicone is environmentally friendly. The raw material for silicone is quartz sand, and although its production process consumes a significant amount of energy, its durability means that the benefits of its long-term use completely outweigh the initial energy expenditure. Silicone can also be recycled through specialized recycling facilities, but this practice is not yet widespread.

Traditional neoprene production requires petroleum, a non-renewable resource. Like silicone, it is difficult to decompose, and recycling is also challenging.

Although traditional neoprene is not environmentally friendly, some manufacturers have developed eco-friendly neoprene made from materials such as sugarcane. These new types of materials may offer a more sustainable alternative.

Applications of Silicone and Neoprene

Food and Medical

In the food and medical fields, silicone holds an absolute advantage. It can be used as a sealant for products that come into contact with food. The sealing ring on the lid of your thermos may be made of silicone. Because of high temperature resistance, inertness to food components, and safety, it is also used to make oven door gaskets, baby pacifiers, silicone baking mats, and tubing for pharmaceutical equipment.

Catheters and prosthetics made from medical-grade silicone are not only flexible but also stable and elastic, ensuring long-term safety for the user.

In the medical field, neoprene is often used to make orthopedic braces to provide support, helping patients recover better and reducing muscle soreness caused by long term contraction. Splints made from this material, which is somewhat elastic but also rigid, are less likely to crack or wear out, and can help stabilize bones for extended periods.

Industrial Field

Applications of Silicone in the Industrial Field

• Custom molds:Molds made with liquid silicone rubber (LSR) can accurately reproduce product details
• High-voltage insulation housings:Provide electrical insulation protection at high temperatures
• Appliance seals, gaskets, O-ring and other sealing components: Provide vibration damping and long-term reliable sealing
• Tube, hose:Durable and chemically inert, suitable for use in high and low-temperature environments
• Potting compounds: High-temperature and insulating sealing

Applications of Neoprene in the Industrial Field

• Seals and gaskets:Durable and oil-resistant,solvent-resistant sealing
• Shock-dampening and sound-dampening pads: A more affordable choice
• Oil and solvent-resistant hoses and pipes
• Cable sheathing material: Abrasion-resistant and weather-resistant
• Gloves or other protective equipment: Better resistance to oils, solvents, and other substances common in industrial manufacturing, less prone to wear or tearing, impermeable to liquids and gases

Automotive and Aerospace

Due to its wide temperature tolerance range and excellent weather resistance, silicone is frequently used in sealing and tubes in the automotive and aerospace industries. Silicone is a good choice for aircraft window seals and hydraulic system O-rings, because of the high demands for long-term elasticity and sealing performance.

Fire-resistant silicone coatings and electrically insulating silicone coatings use silicone’s flame-retardant and electrical insulation properties.

Neoprene is frequently used as a shock-absorbing and sound-insulating material in the automotive and aerospace industries. Engine compartment sound insulation and vibration-damping pads are typical examples of this application. It is also commonly found in the form of hoses, seals, and O-rings.

Construction Industry

In the construction industry, silicone is most commonly found in the form of sealants and gaskets for windows. They provide stable and long-lasting waterproof seals, offering unique advantages over grout, such as resistance to mold growth and the ability to withstand greater stress.

Read Grout or Silicone Caulk: How to Use/When to Use to learn more about silicone caulk.

Neoprene support pads can withstand various chemicals that may be present on construction sites, providing cushioning and support for buildings and bridges. It is also a material used in the formulation of adhesives, improving the weather resistance and adhesion.

Outdoor Products

Silicone folding bowls and water cups offer great convenience for customers engaging in outdoor activities. They are soft and retain their original shape even after repeated folding.

You may have first heard of neoprene as the material used in wetsuits. Neoprene helps divers maintain a warm body temperature underwater. Its excellent mechanical and physical properties protect divers from the risk of their wetsuits tearing or becoming damaged during dives.

Besides being used for wetsuits, its abrasion resistance also makes it a common material for sports equipment such as wrist guards.

Consumer Goods

The silicone pads on the inside of the earphones, which come into contact with the ear canal, are soft and comfortable, as well as less likely to cause allergic reactions. Silicone facial cleansing brushes and beauty scrapers are becoming the preferred beauty tools for many people, because they are less prone to bacterial growth and can be cleaned easily.

Silicone also has cushioning and shock-absorbing properties, making it a common material for mobile phone cases and table corner protectors. Compared to PC material, the soft touch of silicone phone cases provides consumers with a better user experience. Pet products made from silicone materials are also a popular choice. Pet slow feeders and pet toys made from silicone are durable and can provide long-lasting enjoyment for pets.

Due to its durability, neoprene is often used in tool handles and anti-slip mats to provide grip or prevent heat burns to the user. Gloves and shoes made with neoprene linings can keep water out and are resistant to tearing and puncturing. Neoprene can also be used as a fabric for making clothing.

FAQ

What Types of Silicone Are There?

• High-temperature vulcanized silicone rubber (HTV):High tensile strength, suitable for use as a sealing material
• Room-temperature vulcanized silicone rubber (RTV):Cures at room temperature, used in 3D printing and for making sealants
• Liquid silicone rubber (LSR):Commonly used in food and medical applications, more transparent, and has better flow properties
• Fluorosilicone rubber (FVMQ):Stronger resistance to oil and fuel, more suitable for use in fuel systems

Click A Simple Guide to Silicone Rubber Types and Applications to learn more.

What Types of Neoprene Are There?

• Solid Neoprene Rubber:Standard neoprene rubber, more resistant to wear and stretching, commonly used in gaskets
• Closed-cell Neoprene:A type of porous silicone rubber with lower density, has independent air bubbles inside, used in the manufacture of wetsuits
• Open-cell Neoprene: The internal air bubbles are interconnected, so it’s no longer waterproof, but it has stronger shock absorption properties and is used as a cushioning material

Does Silicone Melt at High Temperatures, Like Plastic?

Silicone won’t melt into a liquid, but it can be damaged and decomposed by high temperatures. At slightly elevated temperatures, silicone will harden. Even if the temperature is high enough for the silicone to start burning, it will not continue to burn like wood or other materials. It is a non-flammable material, and its high maximum tolerance temperature makes it very suitable for a machine that works at high temperatures.

Click Silicone Melting Temperature: A Deep Guide to learn more.

Silicone vs. Neoprene vs.Fluoroelastomer(Vition)

For most products, the high-temperature resistance and corrosion resistance of silicone are sufficient. If you need better mechanical strength and resistance to oils and solvents, neoprene is a more cost-effective option. However, if you require a material with even better corrosion resistance and high-temperature performance, fluoroelastomer would be a better choice, but it is significantly more expensive.

Click FKM Rubber vs. Silicone Rubber: Simple Material Selection Guide to learn more.

Final Thoughts

Silicone and neoprene are no longer just industrial materials. They appear in many aspects of life and manufacturing due to their durable properties. High-quality and suitable materials are important for your products to perform as intended during the design phase. Legensilico offers professional silicone selection consulting and wholesale services. Click to learn more!