TPE vs Silicone

TPE or Thermoplastic elastomers and Silicone are both elastomers i.e. they are polymers of rubbery material. They can recover their original shapes after being stretched to great extents. In this blog, we will discuss what is silicone and TPE materials. Moreover, we will also shed light on the main differences in the properties and uses of TPE and silicone.

What is TPE Material?

A thermoplastic elastomer is a flexible and rubber-like substance with plastic-like properties. It may be produced with a range of plastic production equipment such as injection molding, extrusion, and blow molding. TPE plastic material is a genuine thermoplastic that does not require vulcanization or curing. Thermoplastic elastomers are widely used in daily life. These materials are found in a variety of products, including consumer items, medical equipment, power tools, kitchenware, shoe insoles, and motorbike grips. TPE material can resist severe temperatures without warping or splitting.

Thermoplastic elastomers are tear-resistant yet soft to the touch. TPE material is used in grips like those that are commonly found in exercise equipment. TPE is also easily colorable and can be found in products all around us. The soft grips on toothbrushes, dog chew toys, and handles on garden tools are additional examples of TPE applications. Got to TPE injection molding page to know more about TPE molded parts.

TPE material

What is Silicone?

Silicone is a broad category of fluids, resins, and elastomers. Silicones have a general formula of (R2SiO)x. Here, R can represent any of several organic groups. Their distinguishing characteristics include chemical inertness, resistance to water, and oxidation. Moreover, they are stable at both high and low temperatures. Also, they have a diverse set of commercial applications. Go to Silicone injection molding and is silicone safe page to know more.

Composition of TPE plastic

TPE plastic or Thermoplastic Rubber is a copolymer or a blend of polymers that mainly has the properties of rubber with the thermal processability of plastics. The composition usually includes:

  • Elastomeric component: It is a type of network that offers flexibility and elasticity to a network or system.
  • Thermoplastic component: Enables one to forge and reforge, casting, and re-casting.

The ratio of these can be adjusted, and common elastomers used in TPEs are styrene block copolymers (SBC), thermoplastic olefins (TPO), thermoplastic vulcanizates (TPV), and thermoplastic polyurethanes (TPU).

Composition of Silicone

Silicone is a synthetic polymer comprising silicon, oxygen, carbon, and hydrogen with minor proportions of other elements. These elements may include calcium, titanium, or aluminum. Its composition includes:

  • Siloxane backbone: Chains of silicon atoms bonded in turn with oxygen atoms.
  • Organic side groups: Bound to the silicon atoms, depending on the actual type of silicone which can be methyl, phenyl, and others.

What Is the Product Performance of TPE and Silicone?

TPE and Silicone are two polymers and each has its properties and types of polymer to use depending on performance, price, and laws. So, here is the analysis of the product performance of both TPEs and silicone.

1. Thermoplastic Elastomer TPE:

  • Flexibility: Fine, extremely flexible, very soft material.
  • Elasticity: Very flexible, regains the original shape after being bent or during flexing.
  • Processability: Non-biodegradable, easy to mold and recycle, cheaper than metal and glass, and complement each other perfectly since they are both associated with pro plastics.
  • Adhesion: It can easily interact with other thermoplastics and create a good bond.
  • Durability: Somewhat lower, but still higher than non-silicone.

2. Silicone

  • Heat Resistance: Resistant to high temperature as well as not subjected to any type of degrading.
  • Elasticity: Remains flexible at high and low temperatures, therefore, more elastic material should be used.
  • Chemical Resistance: They do not dissolve in water, oils, and many chemicals, they are also waterproof.
  • Biocompatibility: Stable for usage in medicine and cooking.
  • Durability: Highly durable, and long-lasting.

TPE injection molding

Properties of Both TPE vs Silicone Material

Properties TPE (Thermoplastic Elastomer) Silicone
Flexibility Very flexible Flexible but firmer
Elasticity Excellent Excellent
Heat Resistance Up to 120°C Up to 250°C or higher
Melting Point 170°C to 260°C Does not have a true melting point, remains stable up to 250°C or higher
Chemical Resistance Moderate Excellent
UV Resistance Moderate Excellent
Durability Good but less than silicone Very high
Biocompatibility It varies by type Generally high
Processing Easy to process and recycle More complex processing
Cost Generally lower Higher
Tensile Strength 5-30 MPa 5-11 MPa
Elongation at Break 200-800% 100-900%
Hardness (Shore A) 20-90 10-90
Water Resistance Moderate to high High

When to Use TPE palstic material?

Use TPE material when;

  • Cost is a major factor.
  • The temperature resistance is moderate for most of the products.
  • Simple process and recyclability is required.
  • The product requires soft and flexible material;

When to Use Silicone?

Use Silicone when;

  • High-temperature resistance is necessary.
  • Good chemical and UV resistance is crucial.
  • Long-term stability and security must be achieved.
  • The product under consideration is best suitable to be used as medical or food-related products.

Ways to Choose the Best TPE Materials?

Here are some ways that will help you choose the right TPE material;

  • Application Requirements: Find out the strategic requirements of the application you have in mind (e.g., flexibility, hardness & temperature resistance).
  • Mechanical Properties: The tensile strength, elongation, and tear strength have to be tested.
  • Environmental Resistance: Always consider factors such as resistance to UV, chemicals, and heat.
  • Regulatory Compliance: Facilitating compliance with related standards (e.g. of FDA or REACH).
  • Processing Method: Match the TPE to your manufacturing process (for example injection molding, extrusion).

Ways to Choose the Best Silicone Materials?

The following factors will help you understand how to choose the best silicone material.

  • Temperature Range: Choose a silicone that is suitable for the different ranges of temperatures in different applications.
  • Chemical Exposure: Consider the resistance of silicone to different chemicals.
  • Mechanical Properties: Determine the hardness, tensile strength, and % elongation.
  • Regulatory Requirements: Make sure the silicone satisfies certain requirements, such as medical grade silicone or food grade silicone.
  • Special Properties: Look for electrical insulation and transparency of silicon. Besides this, also check the stability of the color.

Silicone molding parts

Is Thermoplastic Elastomer (TPE) Safe To Use?

TPE is considered a safe material in so far as it shall not undergo hard conditions that are likely to damage the Polymer matrix. Safety considerations include:

  • Biocompatibility: TPEs are safe and even good for medical and food contact applications
  • Non-toxicity: Non-toxicity is the general characteristic of most TPEs. However, there may be some dangerous additives included.
  • Regulatory Compliance: Make sure that TEPs meet all the compliance and regulations standards.

You could move to is TPE safe page to know more about TPE material.

Is Silicone Safe To Use?

Silicone is generally safe for different uses in medical and food applications. Safety features include:

  • Non-reactive and Inert: This material has no chemical compatibility issues. It does not chemically interact with most substances that come in contact with it. It makes it directly in contact with food and the skin.
  • Biocompatibility: Medical silicone is used in implants and medical applications.
  • Heat and Chemical Resistance: Under and or extreme conditions, silicone retains its stability hence deeming it safe.
  • Regulatory Compliance: Make sure that the silicone you are using complies with all the requirements of safety.

You could move to is silicone safe page to know more about TPU material.

Differential between TPE vs Silicone

Here are some major differences between TPE vs Silicone.

1. Temperature resistance

Temperature resistance is one of the key distinctions between TPE and silicone. Silicone has no melting point and strong heat resistance. Its mechanical qualities do not degrade at temperatures between 200 and 450°C.

TPE plastic melts between 260 and 320°C. It has a poorer heat resistance. Because of this, TPE material is appropriate for uses that require recyclability and flexibility. They are best for consumer goods, automotive parts, and medical equipment.

2. Chemical resistance

The chemical resistance of silicone and TPE plastic is another difference. Silicone is impervious to the majority of chemicals, water, oxidation, and ozone. It cannot withstand steam, alkalis, acids, trichloroethylene, hydrocarbon fuels, or aromatic hydrocarbons. Because of this, silicone is appropriate for uses requiring a high degree of chemical stability, like insulation, kitchenware, and medical devices. Water, oils, greases, and some solvents are all resistant to TPE. Strong acids, bases, and oxidizing agents cannot break it. Because of this, TPE is appropriate for products that need a modest level of chemical stability.

3. Recyclability

. Because silicone takes high temperatures and specific catalysts to break down its bonds. so, it is not easily recyclable. As a result, silicone is more expensive to dispose of and less environmentally friendly. TPE plastic can be melted and reformed several times without losing its quality. Hence, it is easily recyclable. Because of this, reusing TPE plastic material is less expensive and more environmentally beneficial.

4. Processing method

The fourth difference lies in the processing methods of silicone and TPE material. Processes for handling silicone include liquid injection molding, compression molding, extrusion, and injection molding. Because of this, processing silicone becomes costlier and more difficult. However, it is easy to process TPE.

5. Colours

Both, Silicone Rubber and TPEs provide full spectrum color selections. Silicone rubber is typically translucent when used as a raw material. Colorants used during the manufacturing process mixing stage can produce hues. They can be opaque, translucent, or transparent. But you can easily generate a wide range of colors with TPE.

6. Complex Geometry

Silicone rubber fills extremely long, thin areas of a mold with ease and flows into molds with a range of wall thicknesses.  into a mold to guarantee full fill-out. When developing TPE plastic parts, it is better to radius all sharp corners and maintain as uniform a part wall thickness as feasible.

7. Overmolding

Since Silicone rubber cures at high temperatures.  It reduces the possibility of the substrate melting or deforming.  Overmolded thermoplastic polymers (TPEs) when chosen correctly will produce a cohesive, strong connection with the thermoplastic substrate without the use of primers or adhesives.

8. UV Resistance

A transparent item that has turned yellow due to UV sterilization may still function flawlessly. But still, many people will find it unsettling. Since Silicone rubber is naturally resistant to UV light, it won’t deteriorate in the sun. Typically, these stabilizers work by selectively collecting UV rays. Then release the energy as low-temperature heat.

So, in short, the following table will summarize the major difference between TPE vs Silicone.

 

Feature TPE (Thermoplastic Elastomer) Silicone
Material Type It is a blend of rubber and plastic It is a kind of synthetic polymer
Texture TPE is often softer and more flexible Firmer and even more elastic.
Durability It is less durable and can tear easily, It is more durable and has higher tear resistance
Heat Resistance It offers lower heat resistance. So, it can melt Offers high heat resistance
Cleaning Much simple to clean and contains fewer pores. It requires more care and has more pores.
Lifespan A shorter lifespan. So, it can degrade over time. Longer lifespan and even more stable.
Cost Generally cheaper than other More expensive than TPE
Hypoallergenic Less likely to be hypoallergenic Generally hypoallergenic
Weight Lighter in weight Heavier in weight
Color Options Limited availability, but can fade Available in a wide range of colors and colorfast.
Use Cases Have many applications in making toys, seals, and grips. Highly used to make Medical, culinary, and high-temperature applications.

Silicone material

Conclusion

In conclusion, there are certain parallels and variations between the properties and applications of silicone and TPE. Although silicone is highly resistant to heat and chemicals, recycling it requires complicated procedures  You can select either of the two materials based on your requirements and needs. In general, TPE is more flexible and leads to simple processing. it is a cost-effective solution for making different products at moderate temperatures. Besides this, it is recyclable and fits well with consumer goods. On the other hand, silicone has a high heat resistance and chemical stability. That is why, it can excel in high-temperature conditions. But this is a bit expensive and less flexible as compared to TPE material.

Frequently Asked Questions

Q1. What are the similarities between TPE and Silicone?

TPE and Silicone are similar in many ways such as, they both are elastomers. They both offer rubber-like flexibility and have numerous applications in making different products. Moreover, they are more durable and can be customized for specific properties, These properties make them non-toxic for safe use in medical and food items.

Q2. What are the key differences between TPE and Silicone?

A few properties of TPE are ease of processing, flexibility, and relatively low cost. However, it cannot handle high temperatures. Silicone is heat and chemical-resistant and is used for high temperatures or rigorous use.

Q3. Are TPE and Silicone suitable for medical use?

Absolutely yes, TPE is used in flexible medical applications, such as catheters. Silicone is mostly used due to its high heat stability and biocompatibility for core applications in the medical industry.

silicone parts

Silicone molding parts have become an adaptable plastic fabrication technique. From toy making to shaping custom silicon internal auto car prototypes, silicon molding parts plays a significant role. It yields parts with high dimensional accuracy and tolerances to +/- 0.005x. Before going into in-depth details, it is important to understand some basic concepts related to designing and molding silicon parts. There are a few basic concepts for designing silicon molds that one must need to understand. Let’s discuss these briefly;

What is Silicone Molding?

It is the use of silicone to shape products that can be used. Silicone molding uses diverse methods to get a final product. They include using the block method which is the simplest. It is mixed with other products like liquid soap to get a finer design.

Silicone molding creates flexible materials. It casts a number of items such as polyester, polyurethane wax, plaster, and concrete. Other materials include epoxy resins and polyurethane foam. It makes the materials stronger and chemical resistant. This gives the materials a longer life span.

Design Steps For Silicone molding parts

Step 1: Adjust the Gate Location

Ideally, gates should be located on a silicone part’s hidden and insignificant faces. Since LSR is a flexible material, several gate types are available, and the two most common types are direct gating and sub-gating. Direct gating channels the silicone directly into the mold cavity through the runner system, while sub-gating directs the silicone under the mold cavity to a particular area on the lower part of the component.

Step 2: Parting Lines

Before proceeding with the creation of the mold, it is necessary to decide on the position of the parting line, which is the area where the two halves of the mold are connected and where the silicone part will be located. Typically, the flashing area is found at the parting line of a molded part. Therefore, parting lines should be placed on second and third-level surfaces that are not as noticeable inside the molds.

Step 3: Part Shrinkage

Some of the difficulties that are expected to be observed when molding silicone parts include shrinkage, which ranges between 2-4% of the molded silicone parts.   If a higher quality fabrication is required, then additional steps may be required, and the use of these parts should be taken into account. However, some of them may decrease by an extra 1% from their designed sizes after the molding process.

If a higher quality fabrication is desired, then more steps may be needed, and the application of these parts should be considered.  Nevertheless, certain parts may shrink by an additional 1% from their designed dimensions after molding. Medical component molding can be divided into several types depending on the type of material, size, volume, and molding technology used, among other factors. This article specifically discusses silicone injection molding from a depth perspective.

Silicone molding parts

High Consistency Rubber (HCR) Silicon

HCR has a high viscosity and resembles peanut butter. Usually, It can be catalyzed with either platinum or peroxide. For compounding, a two-roll mill is used with the base material. HCR can be injection molded using two main methods: Compression molding and transfer molding are two of the most important types.

Compression Molding

As the name implies, the material is compressed between the two heated plates in compression moulding. These plates are then compressed, and the material that has been extruded between the two halves is squeezed out along the parting line. However, compression molding is an older technology to mold silicon parts. Despite this, it’s still one of the most affordable ways of fabricating custom molded silicone parts

in small volumes.

Transfer Molding

Transfer molding is somewhat similar to compression molding where high pressure (approximately 1500 to 2000 psi) is used to force the material into a mold cavity. However, it differs in that it employs a runner, sprue and gate system to transfer the material. This method is especially important when it comes to manufacturing silicone parts at low to medium production volume per year.

Overmolding

Afterwards, the silicone material is laminated to the substrate, which gives the final product the characteristics of both materials. This process often employs LSR molding equipment and specific tooling to enhance productivity in the production line. However, some difficulties can be encountered; for example, the insert may be misplaced, which can harm the tooling.

Two-Shot Silicone-Thermoplastic Molding

Like in overmolding, two-shot molding also involves the use of silicone and thermoplastic materials.  First, the first part is injection molded into one half of the mold; then the second part is overmolded silicone onto the thermoplastic molded in the second half of the mold.  Once the mold is opened, the silicone molded parts are released, and the thermoplastic parts are transferred to the silicone overmold side of the mold.  This technology is quite different and involves the use of high temperature resistant tools, self-bonding grade LSR material and skilled personnel to fabricate the required parts.

Difference Between Rubber & Silicon Molding Parts

Rubber molding and silicone molding are two processes with unique features and use. Rubber molding involves high temperature and pressure, whereas silicone molding is carried out at room temperature. This is one of the main differences between the two methods, as the temperature requirements differ significantly.

In rubber molding, a release agent is always needed to prevent the material from sticking to the mold. On the other hand, silicone injection molding usually does not require a release agent, which is beneficial. Moreover, rubber molding is not always accurate and may produce intricate shapes and designs with slight deviations from the original form. Silicone molding, however, is easier to perform and gives shapes that are closest to the mold or the casting material.

Rubber molding mainly generates hard and rigid products, while silicone molding mainly generates products with high chemical resistance. In addition, rubber molding products have low shrinkage rates, meaning they can be stored and used for long periods. On the other hand, silicone products are known to shrink a lot, which poses a problem in storage.

Therefore, rubber molding and silicone molding create numerous designs and shapes; however, they differ in the final products and materials. Rubber molding is particularly useful for producing sturdy and durable parts, while silicone molding produces parts with good chemical resistance. All these methods are important and have their specific roles to play in the manufacturing process.

How does LSR Injection molding work?

Liquid silicone injection molding begins with the CNC machining of the molding tool. This tool is important because it must endure high temperatures during the process. Once the tool is fabricated, it can be sanded to various surface finishes depending on the desired outcome.

The tool is then placed into an LSR-molding machine to start the process. These machines’ presses are designed to have a high level of precision in shot size to enable the production of rigorous quality molding silicone parts. T. LSR is a type of thermosetting polymer, and once it is molded, it cannot be remelted like other thermoplastics resins.

 

After the LSR parts have been injection molded, they are ejected from the mold and can be used as prototype parts production. Injection molded silicone rubber is a flexible material that can be used in various applications across different sectors, such as the medical, lighting, and automotive industries.

molded silicone parts

molded silicone parts

Uses of Molding Silicon Parts

LSR injection molding has a wide range of applications and benefits. It uses pellets made from plastic to mold, making it easier to produce parts and components efficiently. LSR molding has several benefits, including high durability, which makes it ideal for applications that demand the use of parts that can withstand great stress. Also, LSR has a broad range of hardness that can be used to produce products with different hardness levels or elasticity to suit a certain purpose.

 

LSR molding is mainly used to create gaskets, flanges, and cushioning pads in portable communication equipment and ruggedized electronic products. Its durability and ability to perform in extreme conditions suit these and many different applications. LSR injection molding is flexible in terms of molding and designing products, and therefore, it can be used in various product designs and uses. Some characteristics of the material include its high degree of hardness, the ability to reach a wide range of hardness levels, flexibility, and the capacity to meet a wide variety of high-performance requirements in numerous industries.

Design Guide For LSR Injection Molding Parts Fabrication

Several aspects need to be considered when designing for LSR injection molding to increase the effectiveness of the molded parts.

Undercuts add to the complexity and cost of the tool ejection mechanisms, so they should be used sparingly. Another way to minimize the use of undercuts is to integrate pass-thru coring into the design. Undercuts ensure that the parts are ejected from the mold correctly. Therefore, these parts must be designed at minimum draft angles of 0. 5° and up to 5° to facilitate ease of demolding after a shot.

The thickness of the wall is also an important factor that affects the quality of the final product. It also ensures no problems, such as wall sinks and voids in the structure’s wall. Thinner walls are also beneficial in terms of cutting down the cycle time and the total cost of production.

Ribs and gussets are structural elements that should be designed very carefully. The rib’s thickness should be 40-60% of the outer walls while maintaining the necessary draft. This helps provide adequate support to the mold design without exerting excessive pressure.

Hole bosses should be drilled to 30% of the wall thickness. While the edge groove should be 30%. The bosses should best be secured to side walls or ribs to enhance structural behaviour. This design consideration makes the part strong and durable to withstand the test of time and usage.

By following these guidelines, designers can obtain the best LSR injection molding practices, which will help them produce high-quality and relatively cheaper parts at an affordable budget.

silicone cookare molds

silicone cookare molds

Contact Sincere Tech For High Standard Quality Molding Silicone Rubber Parts

Sincere Tech is a professional company that provides custom silicone molded parts services. We have gained the trust and confidence by providing our customers  Rubber Molding Parts & Silicone Molding Parts at competitive prices. Our skilled professionals manufacture this product using advanced technology and quality material to ensure durability and high tensile strength. Moreover, with its superior stability, it is a naturally preferred elastomer for diverse applications, as much as in diverse environments.

We use advanced technology and assure our clients about the optimum performance. Further, we put great emphasis on continuous improvement of the product to ensure it has superior performance to save more labor costs for customers. We are involved in manufacturing and supplying a quality range of  csutom Silicone Molded Parts which is produced using high-grade raw material that is sourced from our respected vendor base, having years of experience in the market.

In addition, these are extruded to manufacture products that can be obtained in both solid and sponge characteristics on multiple extrusion lines. We provide these products with different gradations in size and specifications customizable as per the clients’ exact needs. Our range is in high demand by our client spread across the international market and can be availed at industry leading prices.

Molding can be done using two different materials. It can be rubber or silicone which are both unique. To mold the products, you need a number of items for each of them. Rubber molding and silicone molded parts have the same end result. However, there are distinct differences between the two. Our products include rubber and silicone molding parts, which are good quality and cheap.

  • We use appropriate tools and quality materials to ensure the parts’ structures are strong and durable.
  • Our products guarantee optimum performance and ongoing improvement to reduce the cost of manpower.
  • Our products come in solid and sponge characteristics, and flexibility can be offered to suit the client.
  • Our portfolio products satisfy international demands, and stringent ISO and FDA standards and are reasonably priced in the market.
  • At Sincere Tech, our team of engineers and advanced silicone production equipment ensure that we meet all your silicone mold rubber requirements.
  • Rubber molding and silicone molding are two of the most common types; each has benefits and uses.

Conclusion

In conclusion, LSR injection molding has several advantages: durability, hardness range, and versatility. It can also employ pellets of plastics to ensure its production lines are precise and effective. From gaskets to cushioning pads in electronics, LSR molding is a reliable approach to producing stiff yet elastic parts. This type of injection molding is suitable for various industries and can create intricate designs, which is why it is preferred by companies that aim to produce durable and high-quality products.