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Summary of the Eight Key Features of Liquid Silicone Rubber


Summary of the Eight Key Features of Liquid Silicone Rubber
 
  Liquid silicone rubber products In addition to retaining many of the inherent, characteristic properties of silicone rubber—such as excellent electrical insulation, a wide service temperature range, and long-term weathering resistance under harsh environmental conditions—it also exhibits the following features:
(1) Clean and stable: Liquid silicone rubber contains no solvents or water, ensuring zero environmental pollution; the compound is supplied in two components, both of which have undergone filtration and degassing; the mixed two-component formulation can be stored at ambient room temperature for more than 24 hours, and after cooling and standing, it may remain stable for over 2 days without requiring additional purification.
 
(2) Simple and rapid process
① The two-component rubber compound is mixed in a 1:1 ratio, resulting in a simple compounding process;
② For molded products, from raw material preparation to the finished product, the process can, in principle, be considered a single step, thereby simplifying the manufacturing procedure.
③ Fast vulcanization rate. For example, for compression-molded products produced using a porous mold (with approximately 7 g of rubber compound per cavity), the vulcanization cycle is 20–30 seconds, which is about 1/12 to 1/20 of that for conventional silicone rubber (vulcanization cycle of 4–10 minutes).
④ Unless the product is required to exhibit exceptionally low compression set, post‑vulcanization is generally not necessary;
⑤ Low shrinkage, typically below a few parts per thousand; ⑥ Simple coloring process for the finished product;
⑦ In general, the finished product does not require edge trimming.
 
(3) Energy Savings According to estimates by Dow Corning, the simplification of the process and the change in the vulcanization method can reduce energy consumption by approximately 75%.
 
(4) Low Cost: The processing and production of liquid silicone rubber typically requires only one operator. According to calculations by Dongguan Weishun Silicone Technology Co., Ltd., for a molded part weighing approximately 6 grams, the reduction in labor can cut costs by 42%, and this figure does not even account for the additional savings from lower energy consumption and reduced production space.
 
(5) Low fixed investment: Whether for molded or extruded products, lightweight machinery can replace heavy equipment, and the required factory space can be significantly reduced. What are the advantages of liquid silicone rubber? As a liquid elastomer, it offers excellent flowability, rapid vulcanization, and is safe and environmentally friendly, fully meeting food-grade standards. Liquid silicone rubber can also be used for coating, impregnation, and potting. It is manufactured from silicone rubber products, abbreviated as LSR in English, and exhibits superior elasticity, water and moisture resistance, as well as excellent resistance to corrosion by acids, alkalis, and various other chemicals. Typically, it can replace conventional plastic items; for example, silicone baby bottles and nipples are among the most popular and best-selling liquid silicone rubber products.
 
At the same time, liquid silicone is also the silicone material used in human surgery; it is indispensable in both the cosmetic surgery and physiotherapy industries. Liquid silicone contains no harmful substances and is highly resistant to deformation. It exhibits excellent stability: when no curing agent is added and stored sealed at room temperature (25°C) away from moisture and high temperatures, it can remain unchanged for at least one year.
 
Other characteristics of liquid silicone:
1. Excellent chemical resistance, resistant to acids, alkalis, and a wide range of chemicals;
2. Excellent mechanical strength; products can be formulated to meet varying strength requirements based on customer needs.
3. It exhibits excellent electrical insulation and outstanding dielectric properties; its dielectric performance at elevated temperatures is exceptionally superior, far surpassing that of organic rubbers.
4. Excellent high-temperature compression set: With favorable processing characteristics and easy moldability, it can be manufactured into various products via extrusion–hot-air vulcanization, compression molding, calendering, and other methods.
5. Resistant to stains: marks from ballpoint pens, etc., can be easily wiped away by hand.
6. High production efficiency, relatively high hygiene standards, and generally high product precision.
7. Typically used in baby products, kitchenware, and medical devices, it is safe for direct contact with food and the human body. Liquid silicone rubber boasts a simple processing method: liquid silicone injection molding is an advanced technique that requires only loading the two-component liquid materials into the machine; from mixing to molding, the entire process is fully automated. While streamlining production and reducing cycle times, this method also enables the efficient manufacture of high‑quality parts.
 
The injection molding process not only reduces labor and boosts efficiency, but also delivers a level of aesthetic quality that traditional dip‑molding and brush‑coating techniques simply cannot match. Liquid silicone rubber produced via injection molding is widely used across diverse industries—particularly in electrical, electronic, automotive, and food applications—demonstrating outstanding cost‑effectiveness.
 
Liquid silicone rubber produced via injection molding offers advantages such as high-temperature resistance, corrosion resistance, electrical insulation, and a soft, pleasant tactile feel, and it is FDA‑approved. Its excellent flowability makes it highly suitable for injection‑molding processes. This molding technique enhances product aesthetics, reduces scrap from trimming, and minimizes waste, while single‑step molding on the machine shortens cycle times.
 
The difference between liquid silicone rubber and solid silicone rubber is that one is in liquid form while the other is solid. However, once they are processed into finished products, it becomes much harder to distinguish between them. One key distinction between liquid and solid silicone rubber is their physical state: liquid silicone rubber remains in a liquid state and exhibits flowability, whereas solid silicone rubber is rigid and lacks fluidity.
 
II: Classification by Application Area
1. Liquid silicone is typically used in baby products, kitchenware, and medical devices, and it is safe for direct contact with food and the human body.
 
2. Solid silicone is typically used in household items, industrial components, and automotive parts. 3. Safety of liquid and solid silicones: Liquid silicone is a highly transparent, food-grade material with excellent safety; it is molded without the addition of vulcanizing agents or other auxiliary substances, using a sealed‑charge molding process. Solid silicone is a transparent material that requires a vulcanizing agent to accelerate curing and shorten molding time; it is molded by charging the material into an open mold.
 
3. Classification by Molding Method
1. Liquid silicone rubber is injection-molded liquid silicone rubber (LSR), formally known as injection-molded liquid silicone rubber, and is vulcanized using an injection molding machine. The injection molding process is highly straightforward, delivering high product precision and high throughput—A/B components are mixed at a specific temperature and cured within seconds—while also offering significant advantages such as reduced labor, energy savings, and material efficiency. It can produce all the products traditionally made from high‑temperature silicone rubbers and is poised to become a mainstream technology in the future development of silicone rubber materials.
 
2. In solid‑state silicone molding, the raw material is supplied in solid blocks. After being mixed in a mixer, it is cut by a cutting machine to the appropriate size and thickness for the product and the mold. The pieces are then placed into the mold, where they undergo compression molding at a specified temperature. Upon demolding, the process is similar to that of plastic products, requiring mold cleaning and other post‑molding procedures.
 
4. Based on the finished product: liquid silicone has high transparency, is odorless, and features an injection port; solid silicone has lower transparency, emits a scent from the vulcanizing agent or other masking agents, and lacks an injection port.
 
What are the differences between liquid silicone rubber and solid silicone rubber in terms of molding processes? First, let’s introduce solid silicone rubber.
1. In industry, solid silica gel is produced by hydrolyzing sodium silicate (water glass) in an acidic medium to form a gel, which is then subjected to aging, washing, and drying processes. Depending on its water content, it appears as a translucent or white solid. Commercial products include irregular granular, spherical, and microspherical forms, commonly used as catalyst supports in fluidized‑bed operations.
2. When used as a catalyst support, silica gel is typically impregnated with a solution containing the catalytically active component, allowing the solution to be absorbed into the gel’s pores. Following drying and activation steps, the active component is distributed on the surface of the silica gel. The pore structure of the silica gel—such as its pore volume and pore-size distribution—exerts a significant influence on the properties of the resulting supported catalyst. By convention, silica gel with an average pore diameter of less than 15–20 Å is classified as microporous silica gel, whereas silica gel with an average pore diameter greater than 40–50 Å is referred to as macroporous silica gel.
 
3. However, the fine pore structure hinders the diffusion of reactant molecules, thereby reducing the utilization efficiency of the catalyst’s internal surface area. Moreover, product molecules formed deep within the pores are less likely to escape, which can readily give rise to undesirable side reactions.
 
Silicone can be supplied in the following forms:
1. Compound rubber: This ready-to-use material can be colored and catalyzed to suit your processing equipment and end application.
2. Base compounds: These silicone polymers also contain reinforcing fillers. The rubber base compounds can be further compounded with pigments and additives to produce compound rubber, meeting your color requirements and other manufacturing specifications.
3. Liquid silicone rubber (LSR): This two-component liquid rubber system can be pumped into suitable injection molding equipment and then thermally cured to form molded rubber parts.
4. Fluorosilicone compound and base material: Fluorosilicone retains many of the key properties of silicone; moreover, it exhibits excellent resistance to chemicals, fuels, and oils.
 
A synthetic rubber whose backbone consists of alternating silicon and oxygen atoms, with organic groups attached to the silicon atoms. It strikes an ideal balance between mechanical and chemical properties, making it well suited to meet the demanding requirements of many modern applications. Liquid silicone rubber exhibits high and low-temperature stability, inertness (odorless and tasteless), transparency, ease of coloration, a broad hardness range, resistance to chemicals and weathering, excellent sealing performance, and outstanding resistance to compressive deformation.
 
The foregoing discussion has outlined the differences in the processing procedures of liquid silicone rubber and solid silicone rubber. Compared with solid silicone rubber, liquid silicone rubber is easier to process; its excellent flowability allows for molding, calendering, and extrusion at lower energy consumption, which also underscores its high production efficiency.

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What is the difference between silicone stoppers and rubber stoppers?

Which is better—silicone plugs or rubber plugs? Today, let’s explore their differences and where each excels. First, rubber plugs are a common type of industrial accessory, offering significant advantages such as dustproofing, waterproofing, wear resistance, tear resistance, aging resistance, oil resistance, and protection against ozone exposure. Rubber materials come in various types, and different formulations can be created by combining dozens of chemical ingredients. This allows for tailored properties to meet diverse application needs. For industries requiring tight seals—such as machinery, electronics, transportation, construction, and even aerospace and defense—rubber plugs are often the most suitable choice. Silicone plugs share some similarities with rubber plugs: both can be molded and vulcanized using molds in silicone product manufacturing facilities. However, silicone stands out for being more environmentally friendly, offering superior resistance to high and low temperatures, and providing a smoother, more pleasant tactile experience. It can safely remain in prolonged contact with human skin, which is why it’s widely used in earphone silicone plugs, medical-grade silicone plugs, and food‑grade silicone utensils—largely due to its unique material properties that enable such broad applications. In contrast, silicone plugs emphasize environmental benefits, a soft and comfortable texture, and ease of use. They’re commonly found in electronic devices, everyday household items, and small-scale waterproof or dustproof appliances. Their raw materials are produced through a precipitation process, combining fine silica particles with white carbon black to form a highly refined silicone resin. The resulting molecular structure ensures a soft, flexible material that feels exceptionally comfortable during use. When comparing silicone and rubber, one might liken them to new technology versus traditional industry applications: rubber has long been well‑known and widely used, while silicone products have gained increasing popularity in recent years. Silicone offers greater versatility than rubber, particularly in terms of environmental performance and advanced features like customizable shapes, patterns, and colors. www.mingzhen2006.com


What are the application areas of silicone buttons for devices?

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The convenience brought by industrial silicone buttons

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What are the molding techniques for rubber products?

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How do you print a pattern onto a translucent key?

Some laser marking machines, when used to create translucent keys, can also scorch the transparent plastic parts while removing the paint, leaving them opaque. However, a specialized device installed on Changzhou laser marking machines allows the machine to be configured for laser processing of translucent keys. This enables the laser to cleanly remove surface coatings without damaging the transparent plastic, thus achieving precise laser engraving of translucent keys. Conventional YAG laser marking machines generally cannot produce translucent keys. Translucent keys, also known as light‑transmitting buttons, are commonly used in electronic devices. In dark environments, they allow users to easily and accurately locate each button. A typical translucent key consists of a translucent key body, an electronic switch positioned beneath the key body, and a light‑emitting element mounted on one side below the key body. Beneath the key body is a light guide with a main body; the upper surface of this body extends toward the electronic switch, forming an extension. The outer surface of this extension serves as a first reflective inclined surface, while the lower surface acts as a second reflective inclined surface that also functions as a touch‑sensitive contact surface for the electronic switch. Additionally, there is an optical entry port connected to the extension and aligned with the light‑emitting element. When the light source emits light, it enters through the entry port, strikes the first reflective inclined surface, and is reflected into the main body. Inside the body, the light is further reflected by the second inclined surface and exits through the key body. This design ensures more uniform light emission from the key’s visible surface, enhancing its aesthetic appeal and helping users precisely identify the intended function. The patterns and text on these keys are created using laser marking technology. In our daily lives, many devices feature laser‑marked, translucent keys and buttons—such as mobile phone keys, car audio control buttons, computer keys, and various other electronic appliance switches. www.mingzhen2006.com


What are the basic parameters of silicone rubber products?

Silicone rubber has an extremely wide range of applications due to its non-toxic nature, lack of adhesion to other materials, and ability to withstand repeated steam sterilization. It is extensively used in the medical and food industries, including medical devices, drinking water equipment, sports gear, electronics, electrical appliances, lighting fixtures, audio equipment, toys, security surveillance systems, automobiles, and industrial machinery. Silicone rubber flexible joints are linear polymeric elastomers containing silicon-oxygen bonds, giving them exceptional thermal stability. They also exhibit excellent resistance to ozone aging, oxidative aging, photo‑aging, and weathering, along with superior electrical insulation, mildew resistance, and high gas permeability. Furthermore, they maintain consistent performance across a broad temperature range, from −70°C to +250°C. Thermal conductive silicone sheets are heat‑transfer materials synthesized through a special process, using silicone as the base material and incorporating various auxiliary components such as metal oxides. These sheets offer excellent thermal conductivity and high dielectric strength, and are commonly referred to in the industry as thermal conductive silicone pads, insulating thermal sheets, or soft heat‑dissipation pads. They possess five key characteristics: ease of application, high thermal conductivity, dimensional stability, electrical insulation, and sound absorption and vibration damping. In addition, silicone products manufacturers utilize silicone rubber as a coating or sealant for various vacuum tubes and electrical components, providing moisture resistance, dust protection, and shock absorption. www.mingzhen2006.com

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