When it comes to protecting buildings, vehicles, and industrial equipment from the elements, the quality of the sealing solution makes all the difference. Rain, wind, dust, UV radiation, and extreme temperatures constantly test the performance of every seal and inferior materials fail faster than you think.
For decades, traditional rubber weatherstripping was the default choice for weatherproofing applications. But today, engineers and manufacturers across the globe are making a smarter choice of thermoplastic weather seals made from TPE extruded profiles. These advanced sealing solutions combine the flexibility of rubber with the durability and processability of thermoplastics, delivering performance that traditional rubber simply cannot match.
In this blog, we break down what thermoplastic weather seals are, how TPE extruded profiles are made, and why making the switch is one of the smartest decisions you can make for your next sealing application.
What Is a Thermoplastic Weather Seal?
A thermoplastic weather seal is a sealing component specifically engineered to protect against outdoor environmental factors – water infiltration, air leakage, dust ingress, UV degradation, and temperature extremes. These seals are designed for long-term outdoor or semi-outdoor exposure, maintaining their flexibility and sealing performance year after year.
Common applications for thermoplastic weather seals include:
- Automotive: Door perimeter seals, trunk seals, hood seals, sunroof seals
- Building & Construction: Window frame seals, door weatherstripping, curtain wall gaskets
- Mass Transit: Train door seals, bus window seals, roof hatch gaskets
- Industrial Equipment: Outdoor enclosure seals, control cabinet gaskets
- HVAC Systems: Air handler seals, duct access panel gaskets
What sets a thermoplastic weather seal apart from a standard indoor gasket is its ability to withstand years of UV exposure, ozone attack, freeze-thaw cycling, and physical wear — all while maintaining a consistent, effective seal.
What Are TPE Extruded Profiles?
TPE extruded profiles are continuous-length sealing components produced through the thermoplastic extrusion process using Thermoplastic Elastomer (TPE) or Thermoplastic Vulcanizate (TPV) material. The term “extruded” refers to the manufacturing method – raw TPE pellets are melted and pushed through a precision die to create a continuous profile of a specific cross-sectional shape.
The most widely used material for high-performance TPE extruded profiles is Santoprene™ TPV from Celanese a thermoplastic vulcanizate that delivers rubber-like elasticity with thermoplastic-level processability, consistency, and recyclability.
TPE extruded profiles are available in virtually any cross-sectional shape required for the application — flat strips, hollow bulb seals, U-channels, D-seals, P-channels, T-profiles, co-extruded multi-material designs, and fully custom geometries.
Why TPE Extruded Profiles Are the Smarter Choice for Weather Seals
Many manufacturers still use traditional EPDM rubber or PVC weatherstripping for their sealing needs. While these materials have served the industry for many years, TPE extruded profiles offer a range of advantages that make them the smarter, more future-ready choice.
1. Superior UV and Ozone Resistance
UV radiation and atmospheric ozone are two of the most damaging forces for outdoor rubber seals. Traditional EPDM rubber can crack, harden, and lose elasticity after prolonged sun exposure leading to premature seal failure.
TPE extruded profiles made from Santoprene™ TPV are specifically formulated for outstanding UV and ozone resistance. They maintain their flexibility and sealing performance even after years of continuous outdoor exposure making them ideal for thermoplastic weather seals in automotive, construction, and industrial applications.
2. Wide Operating Temperature Range
A thermoplastic weather seal must perform reliably across the full range of seasonal temperatures from freezing winter cold to scorching summer heat. TPE extruded profiles made from Santoprene™ TPV maintain their flexibility and sealing force from -40°C to +135°C, far exceeding the performance range of many standard rubber weatherstripping materials.
This wide temperature capability makes TPE extruded profiles the first choice for thermoplastic weather seals in extreme climate applications, including automotive door seals, outdoor equipment enclosures, and building façade gaskets.
3. Excellent Compression Set Performance
A weather seal that loses its shape and sealing force over time is a seal that is failing. Compression set the permanent deformation of a seal after prolonged compression is one of the most critical performance metrics for any thermoplastic weather seal.
TPE extruded profiles exhibit outstanding compression set resistance. Even after years of being compressed in a closed door, window, or panel, they spring back reliably to maintain consistent sealing pressure. This long-term resilience dramatically extends service life compared to traditional rubber weatherstripping, which often takes a permanent set far sooner.
4. Consistent Dimensional Accuracy
Because thermoplastic extrusion is a continuous, tightly controlled process, TPE extruded profiles deliver significantly better dimensional consistency than batch-processed rubber products. This means every meter of thermoplastic weather seal fits exactly as designed, with minimal variation in cross-sectional dimensions across the entire production run.
Consistent dimensions are critical for automated assembly operations, where seal installation is performed by robots or automated equipment that requires precise profile geometry to function correctly.
5. Design Flexibility for Complex Seal Geometries
Not all weatherproofing applications can be solved with a standard off-the-shelf seal. Many require complex cross-sectional geometries hollow bulb seals for high-deflection applications, co-extruded profiles combining rigid mounting bases with soft sealing lips, or multi-cavity designs that seal against both water and air simultaneously.
TPE extruded profiles make these complex designs achievable at reasonable tooling cost. Extrusion dies for even complex profile cross-sections cost a fraction of injection or compression molds, making custom TPE extruded profiles accessible even for lower-volume applications.
6. Recyclability and Environmental Responsibility
Unlike vulcanized rubber, which is permanently cross-linked and cannot be reprocessed, TPE materials can be melted and recycled. This makes thermoplastic weather seals made from TPE extruded profiles a more environmentally responsible choice — supporting manufacturers’ sustainability goals and reducing material waste across the product lifecycle.
7. Broad Regulatory Compliance
TPE extruded profiles made from Santoprene™ TPV are available in grades complying with a wide range of industry certifications, including:
- NSF 51 & NSF 61 – for food and drinking water contact applications
- USP Class VI – for medical and pharmaceutical use
- RoHS – for electronics and consumer products
- UL 94 V-0 – for flame-retardant applications
This versatility means thermoplastic weather seals made from TPE extruded profiles can be deployed across heavily regulated industries without additional compliance concerns.
Traditional Rubber vs. TPE Extruded Profiles: A Direct Comparison
| Performance Factor | TPE Extruded Profiles | Traditional EPDM Rubber |
| UV Resistance | Excellent | Good |
| Ozone Resistance | Excellent | Good |
| Temperature Range | -40°C to +135°C | Limited |
| Compression Set | Very Low | Moderate to High |
| Dimensional Consistency | Very High | Moderate |
| Design Flexibility | Very High | Moderate |
| Recyclability | Yes | No |
| Regulatory Compliance | Broad (NSF, USP, RoHS) | Limited |
| Tooling Cost | Low to Moderate | Moderate to High |
| Production Speed | Fast (Continuous) | Slower (Batch) |
As the comparison shows, TPE extruded profiles outperform traditional rubber across nearly every performance category relevant to thermoplastic weather seal applications.
How TPE Extruded Profiles Are Made for Weather Seal Applications
Understanding the manufacturing process helps explain why TPE extruded profiles deliver such consistent, high-quality thermoplastic weather seals.
Material Selection
The process starts with selecting the right Santoprene™ TPV grade – one optimized for outdoor weathering performance, the required hardness, and any applicable regulatory certifications.
Die Engineering
A precision extrusion die is designed and machined to the exact cross-sectional geometry needed. The die must account for material shrinkage, die swell, and draw-down ratio to ensure the finished profile matches the required dimensions precisely.
Extrusion
TPV pellets are fed into a heated extruder, melted to between 160°C and 220°C, and forced through the die under controlled pressure. The profile exits the die as a continuous, hot shape that immediately enters the cooling system.
Cooling and Sizing
The extruded profile is cooled in a water bath or air tunnel, solidifying its shape while a haul-off unit maintains consistent pull speed to control profile dimensions.
Cutting and Finishing
The continuous profile is cut to length using precision cutting systems. Additional finishing operations such as corner welding, adhesive backing application, and custom packaging are performed as required.
Key Industries Switching to TPE Extruded Profiles for Weather Sealing
Automotive OEMs and Tier 1 Suppliers
Vehicle door and window seals made from TPE extruded profiles deliver longer service life, better acoustic performance, and reduced warranty claims compared to standard rubber alternatives.
Architectural and Building Products Manufacturers
Window and façade manufacturers rely on thermoplastic weather seals made from TPE extruded profiles to meet increasingly stringent building energy efficiency standards and weatherproofing performance requirements.
Transit Vehicle Manufacturers
Bus and rail vehicle manufacturers use TPE extruded profiles for door and window seals that must perform reliably through millions of open-close cycles and years of outdoor exposure.
Industrial Enclosure Manufacturers
Manufacturers of outdoor electrical and control cabinets specify thermoplastic weather seals for IP65 and IP66 rated enclosures where water and dust ingress protection is critical.
Conclusion
The evidence is clear – TPE extruded profiles are the smarter, more durable, and more sustainable choice for thermoplastic weather seal applications across every industry. From superior UV and ozone resistance to outstanding compression set performance, wider temperature range, and greater design flexibility, TPE extruded profiles consistently outperform traditional rubber weatherstripping in every measurable way.
If your current weather seal solution is falling short – cracking prematurely, losing its sealing force, or failing to meet regulatory requirements – it may be time to make the switch to TPE extruded profiles and experience the difference that better materials and precision manufacturing can deliver.
About SantopSeal Corporation
SantopSeal Corporation is a leading USA-based manufacturer of thermoplastic weather seals and TPE extruded profiles, serving customers across automotive, building and construction, mass transit, medical, food and beverage, and industrial sectors.
SantopSeal manufactures all products using premium Santoprene™ TPV material from Celanese, delivering consistent quality, outstanding weathering performance, and full regulatory compliance. All products are proudly Made in the USA at SantopSeal’s Pittsburgh, Pennsylvania facility.
Products Offered:
- Thermoplastic Weather Seals & Weatherstripping
- Custom TPE Extruded Profiles (U, P, D, E, H, T Channel and Fully Custom)
- Santoprene™ TPE/TPV Tubing (General, Food Grade, Medical Grade)
- Santoprene Peristaltic Pump Tubing
- Custom & Standard O-Rings
- EPDM Sponge Rubber Seals
- Santoprene Rubber Sheets
- Custom Molded Rubber Products
- Custom Refrigeration Gaskets
- Viton™ Tubing, Cord, Strip & Square
- Flash Knife Cutting Services
- 3D Printing Services
Certifications & Compliance:
ISO 9001 | NSF 51 & NSF 61 | USP Class VI | RoHS Compliant| REACH | UL 94 V-0
Contact SantopSeal Corporation:
- Phone: +1 (412) 444-1888
- Fax: +1 (412) 444-1882
- Email: info@santopseal.com
- Website: www.santopseal.com