When choosing the material of the product, you may wonder about the two materials, silicone and latex, as they look similar, but there are actually many differences. This article will explain it to you in detail to help you make a more appropriate choice when choosing materials.
What Is Silicone?
Silicone is a soft, elastic material with a fine texture. The surface usually has a dry texture and is not easy to absorb dust. It can be made in various colors, or it can be kept in a transparent state. Silicone has basically no obvious odor and is also very low in irritation to the human body. Therefore, products that are often used in direct contact with the human body, such as food and medical applications, are often used.
Chemical Structure
It is a polymer material with a silicon-oxygen bond (Si–O) as the main chain structure and is a synthetic elastomer. Unlike conventional rubber, which has carbon-carbon chains as the main molecular structure, silicone has a more stable structure. This excellent structure makes it have good temperature resistance, aging resistance, and electrical insulation.
Types and Basic Properties
Common silicones in industry include high-temperature vulcanized silicone (HTV), liquid silicone (LSR), and room-temperature vulcanized silicone (RTV). Different types of silicone have different processing methods and application scenarios.
But they all have good environmental stability and are widely used in high temperature, low temperature, long-term exposure to outdoor and food, medical contact industry applications.
Below is a comparison table of different types of silicone, so that you can understand the common characteristics and differences of silicone.
Comparison of Common Silicone Types
| Feature | HTV Silicone | LSR Silicone | RTV Silicone |
| Full Name | High Temperature Vulcanized Silicone | Liquid Silicone | Room Temperature Vulcanized Silicone |
| Curing Method | Cured at high temperatures, typically 150–200°C | Heat-cured rapidly inside a mold | Cures at room temperature through moisture or catalysts |
| Processing Method | Compression molding, extrusion, calendaring | Injection molding | Potting, coating, sealing |
| Key Characteristics | Good mechanical strength, excellent heat resistance, stable performance | High fluidity, precise molding, suitable for automated production | Easy to use, no high-temperature curing required |
| Typical Applications | Sealing rings, gaskets, cable insulation, automotive components | Baby bottle nipples, medical devices, precision seals | Sealants, electronic potting compounds, and construction sealing |
What Is Latex？
Natural latex is a natural material with excellent elasticity. Soft and tough in the hand, extremely stretchable. Natural latex usually appears in a matte surface state, and its color is generally beige or milky white, with a certain natural gas smell. Because it contains protein components, a few people will be allergic to it, causing itchy and red skin.
Its material comes mainly from the milky white sap secreted by rubber trees. After manual collection, filtration, and processing, natural rubber materials can be formed. Latex is a natural biopolymer material.
Chemical Structure
It is mainly composed of cis-1,4-polyisoprene (Cis-1,4-polyisoprene), and the molecular backbone is mainly a carbon-carbon bond (C–C) structure. This structure makes the latex very elastic and flexible. However, compared with the silicon-oxygen structure of silicone, its heat resistance and aging resistance are weak.
It is sensitive to high temperature, oil, and ultraviolet environments. If it is exposed to these environments for a long time, it will age rapidly, harden, and its performance will decline.
Silicone vs. Latex： Material Properties
Thermal Performance
Siliocne
Silicone has excellent high-temperature and low-temperature resistance. It has a long-term temperature tolerance range of -60 to 200℃ and a short-term tolerance of 250 to 300℃. Low temperatures do not harden or catalyze in hot and cold environments.
It is not easy to decompose and oxidize at high temperatures, nor is it easy to have obvious odors. And its heat change is relatively small. The repeated hot and cold shock performance can still remain stable.
Latex
Latex has low temperature resistance. It has a long-term service temperature range of up to 80℃, and if it exceeds this, it is very prone to oxidative cracking. At high temperatures, it will turn noticeably yellow, sticky, hard, and crack. This significantly shortens the service life.
It hardens easily at low temperatures, and its elasticity plummets. And his expansion coefficient is relatively high, expands when heated, and changing size greatly. And after being stressed at high temperatures, it may not be able to fully return to its original shape. Its elastic strength will decrease rapidly when it is exposed to repeated hot and cold changes for a long time.
So it is not as good as silicone in an extreme temperature environment.
Mechanical Properties
Tensile Strength
Silicone
The tensile strength of silicone is at a moderate level, and the overall tensile capacity is average. However, it has a high strength retention rate and relatively stable performance in high temperature or a long-term aging environment. The silicone has a stretch ratio between 100% and 300%.
This is because the main chain of silicone is a silicon-oxygen inorganic structure with high bond energy and strong rigidity of the molecular chain, but the intermolecular force is weak, so it is not easy to form obvious crystalline structures between the molecular chains. Because silica gel lacks a strain crystallization mechanism, its tensile strength is not as strong as that of natural rubber materials.
Latex
The tensile strength of latex is very high, at 15~30MPa. It has a high stretch rate because the main component of latex is cis-1,4-polyethylene pentadiene, which has soft molecular chains and can rotate and stretch on its own. This structure can gradually arrange the molecular chains when stretched, producing a certain crystallization effect, thereby improving the strength and toughness of the material.
Moreover, it also contains a small amount of natural ingredients such as protein, which can enhance toughness to a certain extent, making the overall ductility and tensile properties excellent.
Tear Resistance
The tear strength of silicone ranges from 10–30 kN/m, and the tear resistance is of a moderate level. Because the force between molecular chains is weak and there is a lack of strong intermolecular forces, when a crack is generated in a material, the energy dissipation when the crack propagates is insufficient, and tearing and stretching phenomena are prone to occur.
The strength of the latex in four columns ranges from 30–60 kN/m, and the tearing ability is better than that of silicone. Because its molecular chains are highly compliant, they can disperse stress when subjected to force. It can disperse the force to prevent the crack from expanding, so it is strong and not easy to tear.
Elasticity
Silicone
Reelasticity refers to the ability of a material to return to its original shape after being squeezed or stretched. Silicone has good resilience and is at an intermediate level.
However, during long-term storage of silicone, its elasticity will increase by a certain level. This is because some subsequent cross-linking reaction occurs inside it. Of course, its rebound capacity does not increase indefinitely with time. Its rebound performance is fundamentally affected by the formula.
The main chain of silica gel is a silicon-oxygen structure with high bond energy. The molecular chain has almost no resistance as it rotates, so it loses very little energy when it rebounds, which is relatively smooth.
In complex environments, such as high and low temperatures or long-term pressure, silica gel can also maintain its own structural stability, and the molecules are not easily displaced or broken. So after a long time, the original shape can still be remembered, and the permanent deformation due to compression is extremely small.
Latex
Latex has excellent rebound ability and can quickly rebound to its original shape. Its molecular chain is mainly composed of carbon-carbon bonds. The chain segments are very flexible and can rotate freely, so they can rebound quickly when the force is released and have high initial elasticity.
However, the molecular chains mainly rely on the action of van der Waals forces, and the internal capacity of the material is greatly dissipated. When subjected to force for a long time, there is not enough energy to cause slip. Therefore, the material is easily deformed.
Abrasion Resistance
Silicone
Silicone has average wear resistance. Its surface is easy to wear and scratch, and it will easily fall apart if rubbed for a long time. This is because silicone is mainly based on silicon and oxygen, which have weak intermolecular forces and low surface strength. Under the action of friction, surface molecules are prone to fracture and fall off, so their wear resistance is limited.
Latex
In contrast, latex is more wear-resistant and can withstand more kneading and friction, and is less likely to be damaged. This is because its molecular chain is highly compliant and has good toughness. During the friction process, the molecular chains can be oriented, producing certain crystals and enhancing the interaction forces between molecules.
And the friction energy is consumed by the higher internal consumption, so the overall wear resistance is better than that of silicone.
Electrical Properties
Silicone is an excellent insulation material. It can maintain stable insulation performance under complex environmental conditions. This is because its molecular structure has high bond energy and low polarity. And it does not contain free ions, so it has high resistivity and is not easy to conduct electricity.
The electrical insulation strength of latex is not as good as that of silicone, especially in an environment of moisture or high temperature, its electrical insulation will decline rapidly. Because latex contains natural proteins, moisture, impurities, etc., these components will increase the polarity of the material and easily create conductive channels, resulting in reduced insulation performance.
Environmental Resistance
Silicone
Silicone has good resistance to heat and is very suitable for use in outdoor environments, such as exposure to high temperatures, ultraviolet rays, and ozone. Because silicon-oxygen bonds have extremely high energy and a stable molecular structure, they are not easy to break in ultraviolet and oxidizing environments.
Its structural characteristics are like inorganic matter, which is not easy to oxidize and degrade. So at high and low temperatures, silicone can maintain good elasticity.
Latex
Latex has poor resistance to heat due to its molecular backbone containing carbon-carbon double bonds, which is an unsaturated structure. These double bonds are easily attacked by ultraviolet light, ozone, and oxygen, and the molecular chains break and age.
So it is exposed to ultraviolet light and an ozone environment for a long time, and it is easy to harden, crack, and lose elasticity. So, latex can no longer be used outdoors at high temperatures for a long time.
Silicone vs. Latex： Applications
Silicone and latex have obvious differences in application areas. In general, silicone is more suitable for high-temperature, outdoor, and long-term use environments, while latex is suitable for soft and elastic environments, short-term or indoor use.
Silicone Applications
Construction and Outdoor Engineering
Because its molecular backbone is silicon-oxygen bonds, it is not easily destroyed in ultraviolet and ozone environments, and is not prone to aging, drying, and cracking problems when used outdoors for a long time. In the construction industry, it is used as a sealing material.
For example, as a seal for doors, windows, curtain walls, airports, high-speed railways, and as a seal and waterproofing for photovoltaic modules. In these scenarios, silicone still maintains stable performance.
Automotive Industry
In this field, silicone is often used in components that require high temperature and aging resistance. Because of the high temperature in the engine compartment, vibration, and an oil environment. Silicone can cope with these complex working conditions.
Therefore, it is often used as a component, such as an engine seal, spark plug hose, high temperature line, sealing wiper protective cover for headlights, etc. It is able to maintain good sealing performance in high and low temperature changes and a long-term use environment.
Electronic
Silicone has good electrical insulation properties and is resistant to aging, moisture, and chemical corrosion. In this industry, silicone is often used as an insulation, sealing, and waterproofing material, such as electronic equipment sealing rings, electrical insulation parts, and high-temperature resistant components.
It can also be used as a high-temperature resistant component in some household appliances, such as induction cookers, ovens, water heaters, and other environments.
Medical and Food Contact Products
Silicone is non-toxic, odorless, chemically inert, and resistant to high temperature sterilization. Under normal use conditions, the material is structurally stable and not prone to the precipitation of harmful substances, making it very suitable for food contact and medical fields. It is often used as a baby pacifier, a straw, a food seal, a medical catheter, a respiratory mask gasket, etc.
Industrial Sealing and Chemical Equipment
In industrial environments, equipment often needs to withstand high temperatures, chemical media, and complex working conditions. Silicone has good chemical resistance and aging resistance, and can maintain stable performance in strong oxidizing environments, ultraviolet irradiation, and high and low temperature changing conditions.
Therefore, it is often used as an industrial sealing material, such as a chemical equipment gasket, an industrial sealing ring, and high temperature resistant seal.
Latex Applications
Medical Disposables
Latex is a common raw material in the light industry because it has high elasticity, is soft and ductile, and is very suitable for use in one-time gloves, inspection gloves, etc. This type of product requires materials with good fit, flexibility, and stretching ability.
Daily Necessities
The latex has a very good molecular weight, softness and elasticity, high elongation, and a strong fit. The human body is comfortable to wear, so it is often used for disposable gloves, balloons, cleaning supplies, etc.
However, its main chain contains carbon-carbon unsaturated double bonds, which are easily oxidized and destroyed by ultraviolet light, and will then age and lose elasticity. So it is suitable as a product for short-term use, not for long-term outdoor use.
Interior Building Materials
In built interior environments, it is often used as a coating and caulking material. Such as common interior wall latex paint and some interior sealing materials. Latex has good film-forming properties and strong adhesion. It is easy to construct, and it is less expensive and is more commonly used in interior decoration.
Its weather resistance is average, and its indoor environmental conditions are relatively simple. It will not be affected by ultraviolet rays and ozone for a long time, so it can be used indoors to make up for this shortcoming.
Silicone vs. Latex： Cost
Raw Material
In terms of raw materials, latex is more economical. Latex is obtained by naturally harvesting the sap of rubber trees. Its costs mainly come from planting, tapping labor costs, land, primary processing, and transportation costs.
The production process is relatively simple. Silicone is a silicone elastomer, and its cost mainly comes from high-purity silicon raw materials, complex catalytic processes, and technical barriers. So the raw material price is also high.
Processing
In terms of processing, silicone requires high-temperature vulcanization or liquid silicone injection molding, which has high equipment and process requirements. Therefore, its unit processing fee is very high, and small batches will be more expensive.
Latex products are generally made using simple processes such as impregnation molding. Latex, on the other hand, has a low unit cost and can be produced in large quantities, with relatively low spare inputs and labor costs.
How to Choose Between Silicone and Latex
Use Environment
If the scene you need to use is in high and low temperatures, ultraviolet, ozone, and other environments, you should first choose silicone products, which have good weather resistance.
If you plan to use it indoors, without long-term exposure to sunlight and ozone, and in a stable temperature environment, you can choose to use latex.
Mechanical Performance Requirements
Silicone is not easily deformed when subjected to long-term pressure, and its compression permanent shape is small, making it suitable for use as a seal or a component that needs to maintain a stable shape for a long time. Latex has high tensile strength and softness, making it suitable for use on products with high elasticity and good ductility.
Service Life Requirements
Silicone has good aging resistance. It has stable performance in high temperatures, ultraviolet light, or complex environments, and generally has a long service life. Latex is more susceptible to aging under the action of heat, oxygen, or ultraviolet light, and will slowly harden, crack, and lose elasticity, making it more suitable for short-term use or disposable products.
Whether Food-grade and Medical-Grade Are Required
If the scenario you need to apply requires food-grade or medical grade, you choose silicone material. Silicone is chemically inert, non-toxic, and odorless, and can be sterilized at high temperatures. Latex contains natural proteins and may cause allergic reactions in some people. It should be used with caution in this field.
Cost Budget
As mentioned earlier, silicone is more expensive than latex. If you are more cost-sensitive and the product is suitable for large-scale production, single-use products, or short-term use products, you can choose latex. If you require more long-term quality performance than cost and high weather resistance, you choose silicone.
FAQ
Which Is Safer, Silicone or Latex?
Silicone will generally be considered a safer and more stable material. It does not release harmful substances under normal conditions of use, is not irritating to humans, and can be used in food contact and medical products. Latex contains natural protein components that may cause irritant allergic reactions in the body.
Which Is Greener, Silicone or Latex?
Latex is derived from the sap of rubber trees and is more susceptible to degradation in the natural environment. Silicone is a synthetic material that degrades more slowly, but it generally has a longer service life and can be replaced less frequently, thus providing some protection to the environment. So both materials have certain environmental protection.
Final Thought
Legensilicone is a supplier specializing in the research, development, and manufacturing of silicone materials and products. We can provide stable product quality as well as flexible customized service. Our products are used in multiple industries and are continuously optimized. Welcome to connect with us anytime.
