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Molded Silicone Rubber: LSR’s High Sealing Force Throughout a Product’s Lifetime

By 6.8 min readPublished On: May 30th, 2023Last Updated: May 30th, 2023Categories: Silicone industry knowledge

Molded silicone rubber (LSR) has revolutionized the sealing industry with its exceptional properties and manufacturing process, ensuring high sealing force and longevity for a wide range of products. In this article, we will delve into the superior sealing performance of LSR, its applications across various industries, the manufacturing process, and the key benefits it offers. Let’s explore the world of molded silicone rubber and discover how it enhances product integrity throughout its lifecycle.

Understanding Molded Silicone Rubber (LSR)

Molded silicone rubber, commonly referred to as LSR, is a versatile elastomer that possesses unique properties, making it an ideal choice for sealing applications. LSR is produced through a precise and controlled injection molding process, resulting in consistent quality and excellent sealing performance.

LSR’s key attributes include exceptional chemical resistance, remarkable thermal stability, flexibility for dynamic sealing, and a long service life. These properties make LSR stand out among other sealing materials and contribute to its widespread adoption across industries.

Superior Sealing Performance of LSR

LSR exhibits an unparalleled sealing force, surpassing traditional sealing materials in various aspects. One of the key factors contributing to its exceptional sealing performance is its compression set resistance. Compression set refers to the ability of a material to recover its original shape and sealing force after being subjected to compression.

LSR’s low compression set enables it to maintain a reliable and durable seal, even under extreme pressure or fluctuating temperatures. This ensures that products sealed with LSR remain protected and functional throughout their entire lifespan.

Furthermore, LSR demonstrates excellent chemical resistance, making it suitable for applications exposed to harsh environments and chemicals. Whether it is corrosive substances, solvents, or fluids, LSR maintains its integrity, protecting the product and preventing leaks or contamination.

Another significant advantage of LSR is its remarkable thermal stability. It can withstand both high and low temperatures without compromising its sealing effectiveness. This makes LSR an ideal choice for applications where temperature variations are expected, ensuring optimal performance in challenging conditions.

Enhanced Chemical Resistance

LSR’s exceptional chemical resistance makes it a preferred choice for sealing applications in industries such as automotive, healthcare, and electronics. In the automotive industry, LSR is widely used for sealing engine components, fuel systems, and electrical connectors. It withstands exposure to various automotive fluids, such as oils, fuels, and coolants, without deteriorating or losing its sealing properties. Additionally, LSR’s resistance to chemicals and solvents makes it suitable for sealing applications in the healthcare industry, including medical devices, drug delivery systems, and surgical instruments. LSR ensures sterility, patient safety, and long-term functionality in these critical applications.

Excellent Thermal Stability

LSR’s remarkable thermal stability is a valuable characteristic that contributes to its sealing effectiveness in extreme temperature conditions. In industries such as aerospace and energy, where components are subjected to high heat or cryogenic temperatures, LSR maintains its sealing force, protecting sensitive equipment and ensuring reliable performance. Furthermore, in consumer electronics, LSR’s ability to withstand temperature variations and thermal cycling ensures the integrity and longevity of electronic devices. Whether it is smartphones, wearables, or home appliances, LSR seals provide a barrier against moisture, dust, and temperature-related issues.

Flexibility and Elasticity for Dynamic Sealing

LSR’s inherent flexibility and elasticity enable it to adapt to dynamic sealing requirements. This is particularly advantageous in applications involving rotating or oscillating parts, where the seal needs to accommodate movements, vibrations, and fluctuations. LSR’s flexibility allows it to conform to irregular surfaces and maintain a secure seal, even in challenging operating conditions. This characteristic makes LSR suitable for applications such as pumps, valves, and hydraulic systems, where dynamic sealing performance is crucial for efficient and reliable operation.

LSR Applications and Benefits

Molded silicone rubber finds extensive use in various industries, offering numerous benefits that enhance product performance, durability, and safety.

Medical Devices: Ensuring Sterility and Patient Safety

In the medical field, LSR plays a vital role in sealing critical devices and components. Its high sealing force, biocompatibility, and exceptional chemical resistance make it suitable for applications such as surgical instruments, implantable devices, and drug delivery systems. LSR ensures sterility, patient safety, and long-term functionality, as it resists the degradation caused by exposure to bodily fluids, harsh disinfectants, and medical-grade chemicals.

Automotive Components: Protecting Against Fluid and Environmental Intrusions

LSR’s sealing capabilities make it an invaluable material for automotive components, protecting against fluid leaks, dust, and other environmental factors. From engine gaskets and seals to electrical connectors and sensors, LSR ensures optimal performance, prolongs component life, and enhances overall vehicle reliability. Moreover, LSR’s resistance to automotive fluids and its ability to withstand temperature variations contribute to the longevity and functionality of automotive systems, ensuring safe and efficient operation.

Consumer Electronics: Preserving Device Integrity

In consumer electronics, LSR contributes to the reliability and longevity of devices by providing effective sealing against moisture, dust, and other contaminants. Whether in smartphones, wearable devices, or home appliances, LSR ensures product integrity, safeguarding sensitive electronics and enhancing their performance and lifespan. LSR’s sealing properties protect electronic components from environmental factors, enabling devices to withstand everyday usage, various weather conditions, and occasional exposure to liquids.

Manufacturing Process of Molded Silicone Rubber (LSR)

The manufacturing process of LSR involves advanced techniques to achieve consistent quality and precise sealing performance.

Injection Molding: Achieving Complex Designs

Injection molding is the primary method used to produce LSR components. This process allows for the creation of intricate designs and customized shapes, ensuring a perfect fit and superior sealing performance. LSR’s low viscosity enables it to flow easily into complex mold cavities, ensuring the replication of intricate details with high precision. The injection molding process for LSR involves the following steps: material preparation, injection molding machine setup, injection of the LSR material into the mold, curing or vulcanization, and part ejection. Each step is carefully controlled to achieve the desired physical and sealing properties of the final product.

Quality Control and Testing

To ensure the reliability and durability of LSR sealing solutions, rigorous quality control measures and testing procedures are implemented throughout the manufacturing process. This includes inspections for dimensional accuracy, compression set resistance, chemical compatibility, and other critical parameters. Quality control technicians perform visual inspections, measurement tests, and functional tests to ensure that each LSR product meets the highest quality standards. Advanced testing methods, such as hardness testing, tensile testing, and thermal cycling, are employed to evaluate the physical properties and performance of LSR seals. These stringent quality control processes guarantee that LSR sealing solutions provide consistent and reliable performance in various applications and environments.

Molded silicone rubber (LSR) has emerged as a game-changer in the sealing industry, offering superior sealing performance and long-lasting integrity for a wide range of products. Its exceptional properties, including high sealing force, chemical resistance, thermal stability, and flexibility, make it an ideal choice for various applications across industries. From medical devices to automotive components and consumer electronics, LSR’s contributions to product performance, safety, and longevity are undeniable. By embracing LSR in manufacturing processes, companies can ensure that their products remain sealed and protected throughout their entire lifecycle, enhancing customer satisfaction and overall product quality.


Q: Is LSR suitable for applications requiring resistance to harsh chemicals?

A: Yes, LSR exhibits exceptional chemical resistance, making it highly suitable for applications exposed to aggressive chemicals, solvents, or fluids.

Q: Can LSR withstand extreme temperature conditions?

A: Absolutely, LSR possesses excellent thermal stability, allowing it to maintain its sealing effectiveness across a wide temperature range, from extreme heat to freezing cold.

Q: Is LSR flexible enough for dynamic sealing requirements?

A: Yes, LSR’s flexibility and elasticity enable it to adapt to dynamic sealing needs, accommodating movements, vibrations, and fluctuations without compromising performance.

Q: In which industries can LSR be found?

A: LSR finds applications in various industries, including medical devices, automotive components, and consumer electronics, due to its exceptional sealing capabilities and benefits.

Q: How is LSR manufactured?

A: LSR is primarily produced through the injection molding process, which allows for intricate designs, customization, and precise sealing performance.

Q: Does LSR undergo quality control and testing?

A: Yes, LSR manufacturers employ rigorous quality control measures and testing procedures to ensure the reliability, durability, and adherence to high-quality standards of LSR sealing solutions.