Silicones are synthetic rubbers that are often used as substitutes for plastic. They are also found in a variety of other consumer products, including baby bottle nipples, toys, mugs, and food containers. Silicone is also used in sealants, lubricants, gaskets, and medical applications.
Silicones, also known as siloxanes, are a hybrid of synthetic polymers and rubbers. Silicones can take on different forms, from soft, malleable rubber to hard plastic-like resins and thick, spreadable fluids.
Silicone VMQ Q MQ PVMQ
The molecular structure of methyl silicone is unique and contains repeat units of oxygen, which gives it excellent resistance to ozone, UV, and weathering.
Despite its unique molecular structure, methyl silicone is not very common in the market and requires processing in order to improve its elastomeric properties. Vinyl methyl silicone (VMQ) and FVMQ are both similar in terms of chemical and mechanical properties but differ in their tensile strength and weathering resistance.
The difference between VMQ and PVMQ is primarily the vinyl content of the VMQ. Higher vinyl content improves tensile strength, but too much vinyl content can lead to excessive crosslinking density, making the glue too stiff.
In contrast, high MQ silicone resin increases the hardness of the resulting material and increases its tensile strength, tear strength, and adhesion. However, as the amount of MQ silicone resin increases, the crosslinking density decreases.
Ethylene Propylene Rubber EPDM
If you are looking for a high-quality elastomer to use in a variety of applications, look no further than silicone. This material is superior to EPDM because it provides additional benefits and longer service life.
It can be manufactured in several ways and is available in three basic forms: liquid silicone rubber, room temperature vulcanization, and high-temperature vulcanization.
EPDM is transparent and flexible. It can be used for athletic gear, waterproofing of expansion joints, pool liners, and insulating applications. It is also useful for heating and cooling systems.
EPDM’s flexibility and resilience make it an excellent choice for cable and wire harnesses, bumpers, and brake systems. Besides being flexible and resilient, EPDM is also food-grade and safe for use in a variety of applications.
The Buna-N/Nitrile N-Bisphenol-R (NBR) rubber is a versatile polymer that is particularly resistant to petroleum and aliphatic hydrocarbons. Its properties also extend to hydrocarbons, vegetable oils, and silicones.
These materials are odorless and also exhibit good resistance to water, sunlight, and ethylene glycol. However, unlike NBR rubber, Buna-N does not have any chemical toxicity or fouling properties.
Nitrile rubber is a synthetic compound made by copolymerizing butadiene with acrylonitrile. It has a wide temperature range, is non-toxic, and is a suitable material for hydraulic fluids and repeat food exposure.
Among its many uses, Nitrile is a perfect choice for custom moulded components and seals, as well as applications that need high-tensile strength and resistance to oil.
Developed for applications in hydraulics, plastics, rubber products, and other industrial uses, Viton® FKM Silicone Materials offer a variety of performance advantages over other materials.
These O-Ring Seals have excellent resistance to high temperatures, petroleum products, and ozone. In addition, they feature a wide range of chemical compatibility. Here are three reasons to choose Viton. Let’s start with its advantages:
Fluoro-elastomer, FKM, and FPM are three common names for the materials. The original company that developed them, Du Pont, now manufactures them under several brand names.
They are commonly abbreviated as FKM or FPM, according to the American ASTM and DIN/ISO systems. Seals offer food-grade Viton O-Ring Seals. They can also provide EC1935/2004-certified Viton O-Ring Seals.
Neoprene CR silicone materials are a versatile type of elastomer. Often used as a construction material, they exhibit excellent durability and offer excellent resistance to weathering and corrosion. They also have excellent mechanical properties and are used in a variety of applications, including food processing, construction, and medical settings.
Extruded neoprene water stops are commonly used in the construction and remodeling industry, while lockstrip-type neoprene gaskets are commonly used in the automotive industry.
Chloroprene can be produced by chlorinating isoprene or butadiene. Both are emulsified with water and then polymerized using free-radical initiators.
Chloroprene repeating units may take one of several structures, but the most common is istrans-polychloroprene. The interlinking of chloroprene occurs through metal oxides. This type of silicone is regarded for its high tensile strength, elongation, and resistance to moisture.
Types and Sizes of O-Ring Seals
There are many different kinds of O-Ring Seals, some of which are harder than others. While some materials are used in general applications, more extreme applications tend to fall back on time-tested materials. Four of the most difficult specialty O-Ring Seals materials are nitrile, PTFE, silicone, and Viton.
In general, most O-Ring Seals are considered static axial seals, meaning they create a tight seal between two parts. In this way, they are often made of materials with lower abrasion and tearing resistance.
There are several different materials used in manufacturing O-Ring Seals. The EPDM, or ethylene propylene diene monomer, material is one of the most common. EPDM is highly resistant to heat, alkalis, and oxygenated solvents. It is popular for hydraulic applications and can withstand brake fluids. However, EPDM is not recommended for use with hydrocarbons.
Another material used in manufacturing O-Ring Seals is silicone. Silicone is a family of polymers, including silicone rubber. These materials have excellent heat resistance and are frequently used in electronics, manufacturing, and pharmaceutical industries.
Depending on the application, these materials may have different hardnesses. For example, the Nomenclature for rubber and latices is SS-ISO 1629. The list below shows which materials are compatible with various service fluids, indicating which may be compatible with particular materials.
The application temperature should be agreed upon between the user and manufacturer. O-Ring Seals should also be durable enough to withstand high temperature ranges.
There are different types and sizes of O-Ring Seals. CS, or cross section, is the measurement of the width of the material used to create the ring.
To determine its CS, lay the O-Ring Seals flat on a surface. O-Ring Seals have CSs between 0.040 and 0.070 inches, or 0.135 and 0.139 mm, respectively. O-Ring Seals are also available in metric and cord stock sizes.
The Society of Automotive Engineers published an AS568 O-Ring Seals sizing chart for aerospace applications. The AS568 size chart provides the dimensions of inner and outer diameters, cross-sections, tolerances, and size identification codes for O-Ring Seals used in sealing applications.
It also recommends gland design and material type. Most manufacturers use these sizes as a standard. But if you’re not sure which size to order, you can consult the AS568 sizing chart to ensure that you are getting the right one.
O-Ring Seals are essential components of the petroleum industry. From oil refining to transportation, O-Ring Seals are used to seal valves and other parts.
As such, the environments are often harsh. Oil and fuel products are often mined in very harsh conditions. Because of this, specially made O-Ring Seals must perform under these conditions and to higher standards. When choosing O-Ring Seals, you can find a perfect fit for your application.
An O-Ring Seals is a small, flexible rubber component used to seal a gap. O-Ring Seals come in many sizes and are used in many types of applications. They can be static or dynamic and are used for radial and lateral loading.
The design of an O-Ring Seals is relatively straightforward. To make the process of manufacturing a ring easier, learn about the characteristics of different types of O-Ring Seals.
Typical O-Ring Seals materials vary, depending on the application and working conditions. In some cases, O-Ring Seals are made of Teflon, but it’s rare to find these products in these applications.
For most applications, however, rubber compounds are used, and they fall into four major categories: NBR, VITON, SILICON, KALERZ, and HNBR. Depending on the conditions of your application, you’ll want to choose a ring that has an appropriate hardness rating.
The reliability of O-Ring Seals depends on the parameters that affect them. The maximum compression stress of an O-Ring Seals is represented in Figure 8. This characteristic is affected by various processes. For example, the material used to make the O-Ring Seals can be affected by the type of process.
The following section describes the characteristics of different types of O-Ring Seals. Each characteristic influences the reliability of the product. Depending on the material, it may be made of a variety of materials.
The contact force of an O-Ring Seals is determined by its initial cross-section diameter. As a result, the ring undergoes compression and is forced to return to its resting position. The ring’s material can be abrasive, soft metal, or a combination of these materials.
In addition, the pressure in the contained fluid cannot exceed the contact stress of the O-Ring Seals. However, there are certain instances where the O-Ring Seals fails due to high-pressure extrusion through the mating parts.