IOTA 2056 HTV Ethyl Silicone Rubber Selection and Application Verification Method
IOTA 2056 HTV is an ethyl-containing silicone rubber (HTV) obtained by introducing ethyl groups into the side chains of dimethyl polysiloxane. Its glass transition temperature can be as low as -147℃, making it one of the silicon rubbers with the most outstanding low-temperature resistance at present. It also has constant elastic modulus and constant damping factor, making it suitable for applications such as deep cryogenic equipment, high-latitude and high-altitude areas, aerospace, deep-sea exploration, and damping and vibration reduction in precision electronic devices.
Is it possible to directly replace an ethyl-containing silicone rubber with a similar ethyl content and hardness? No. When selecting the type, one should first confirm the ethyl content, vulcanization system, vulcanization conditions, low-temperature elasticity retention rate and damping stability. Then, based on the actual working conditions such as deep cold sealing, low-temperature vibration reduction, damping devices, etc., evaluate the mixing processing performance, vulcanization quality, low-temperature rebound, compression permanent deformation and long-term stability. Ultimately, whether to adopt it should be jointly confirmed by the small-scale test of the mixing formula, trial production and product verification.
Compare the key indicators under the same conditions
IOTA 2056 HTV provides two models: HTV-1 with an ethyl content of approximately 20 mol%, and HTV-2 with an ethyl content of approximately 50 mol%; both have vulcanized rubber hardness of Shore A 50. Product specifications
Model Ethyl content Hardness Stretch strength Tear strength Extension at break
Model Ethyl content Hardness Stretch strength Tear strength Extension at break
IOTA 2056 HTV-1 20 mol% Shore A 50 9.0 MPa 31 N/mm 560%
IOTA 2056 HTV-2 50 mol% Shore A 50 8.0 MPa 23 N/mm 580%
The vulcanization conditions are: 50% solid diene 2,5, 170℃ for 20 minutes, 200℃ for 30 minutes. Product specifications
Before making inquiries and sending samples, both parties should clearly define the following information:
Ethyl content and molecular structure: Confirm the selection of 20 mol% or 50 mol%, as well as the distribution pattern of ethyl groups on the main chain. The ethyl content directly affects low-temperature elasticity, crystallization inhibition ability, and the upper limit of heat resistance.
Sulfurization system and sulfurization conditions: Confirm whether to use double 2,5 or other organic peroxides, and whether the sulfurization temperature, time, and requirements for two-stage sulfurization are consistent.
Verification conditions for low-temperature performance: Confirm the test methods for glass transition temperature, low-temperature rebound, compressive cold resistance coefficient, low-temperature brittleness temperature, and low-temperature compressive permanent deformation.
Damping and constant elasticity performance: If used for precise vibration reduction, confirm the stability of elastic modulus within the temperature range, damping factor stability, and frequency response.
Heat resistance upper limit: Ethyl silicone rubber has excellent low-temperature resistance, but the introduction of ethyl groups will reduce heat resistance. The normal operating temperature is generally not more than 225°C, and it needs to be matched with the actual working conditions.
The procurement specifications should clearly state the allowable range, testing methods, and acceptance conditions, rather than just stating a nominal value.
Which differences are worth checking apart from ethyl content
Comparison items How to compare Relation to application
Comparison items How to compare Relation to application
Ethyl content Confirm the mol% value and the measured range of the batch Decide on low-temperature elasticity, crystallization inhibition degree, and heat resistance upper limit
Sulfurization curve and sulfurization agent Compare under the same double 2,5 dosage, temperature, and time Effect on burn-off safety, sulfurization speed, and crosslink density
Low-temperature elasticity and compressive permanent deformation Test rebound, hardness, and compression retention rate at the target low temperature Core acceptance items for deep cold sealing and low-temperature vibration reduction
Damping stability Compare at the target temperature, frequency, and amplitude Ensure constant elasticity modulus and constant damping for precise electronic equipment vibration reduction
Heat resistance and aging Compare changes in hardness, tensile and elongation after high-temperature aging The heat resistance upper limit of ethyl silicone rubber is lower than that of ordinary silicone rubber, and it needs to be carefully confirmed
Determine verification priorities according to the application
Deep cold equipment and high-altitude sealing applications
Compare compressive permanent deformation, rebound rate, hardness changes, and leakage performance at the target low temperature. The glass transition temperature of ethyl silicone rubber can reach -147°C, but whether the product can maintain sealing ability at -70°C, -100°C or lower temperatures should be verified by the actual formula and product structure.
Aerospace and deep-sea exploration applications
In addition to low-temperature performance, it is also necessary to pay attention to the mechanical retention rate after high-low temperature cycles, compressive relaxation, vacuum volatilization, and medium compatibility. If in contact with fuel, hydraulic oil, or other media, it is necessary to verify volume swelling and performance attenuation separately.
Precision electronic equipment damping and vibration reduction applications
Compare the stability of elastic modulus, damping factor, creep, and long-term attenuation under the target temperature, vibration frequency, and load conditions. This product has the advantages of constant elasticity modulus and constant damping factor, but the specific values need to be confirmed in actual working conditions.
Molded and extruded product applications
Maintain the consistency of silica, structure control agent, sulfurization agent, and mixing process, observe the powder consumption speed, mixing uniformity, burn-off safety, and the appearance of the extruded surface and the appearance after sulfurization. Different ethyl content will affect the rheological properties of the mixed rubber and the mechanical balance of the sulfurized rubber.
How to verify from samples to mass production
First, agree on the acceptance items
Keep the batch records of the current raw rubber or mixed rubber, sulfurization curves, low-temperature rebound, compressive permanent deformation, and failure data of the finished product, and convert them into checkable items.
Do a small test under the same conditions
Keep the current materials as a control, and test the candidate materials under the same fillers, sulfurization agents, sulfurization temperature, and time. When the formula needs to be adjusted, set up another test group and record the reasons.
Test in real working conditions
After the small test meets the requirements, verify the mass mixing, molding/extrusion, actual mold, stability of continuous production, and consistency of the finished product. The verification temperature, number of cycles and aging time should be determined based on the product lifespan and application risks.
The results should be documented in the procurement and change requirements.
Record the approved range of ethyl content, hardness, tensile strength, tear strength, elongation, low-temperature performance limits, vulcanization conditions and testing methods. Agree on COA, retention samples, batch traceability and change notifications.
The basis for judgment should be the pre-agreed acceptance criteria, rather than "ethyl content close to" or "hardness the same". If the candidate material only passed a certain test, the conclusion should also be limited to that test and corresponding conditions.
What information should be prepared before inquiring from the supplier
You can provide an unclassified application summary first: material usage, target ethyl content (20 mol% or 50 mol%), temperature range of use, whether it involves cryogenic or damping vibration, molding process, vulcanization system, filler system, contact medium, current problems encountered, target market and expected purchase volume. When there are requirements for low-temperature rebound, compressive permanent deformation, damping stability or heat resistance upper limit, the testing methods and acceptance criteria should also be specified.
As a solution provider for the entire organic silicon industry chain, Aijota can discuss candidate specifications for the material range and customer conditions of IOTA 2056 HTV ethyl silicone rubber. After the initial selection, the corresponding technical materials, safety materials and batch inspection documents should be checked. The specific applicability is confirmed through actual application verification.
FAQ
1. How to choose between HTV-1 and HTV-2?
Both have the same hardness, but the ethyl content is different. HTV-2 has a higher ethyl content, theoretically maintaining better low-temperature elasticity, but its tear strength and tensile strength are slightly lower; HTV-1 has higher mechanical strength and is suitable for scenarios with more explicit strength requirements. The choice should be based on a comprehensive balance of low-temperature performance and mechanical performance.
2. Can ethyl silicone rubber replace ordinary silicone rubber?
It cannot be simply replaced. Ethyl silicone rubber has obvious advantages in low-temperature resistance, but its heat resistance limit is usually lower than that of ordinary methyl vinyl silicone rubber, and the normal operating temperature is generally not more than 225℃. If the working conditions require both low and high temperatures, the low-temperature elasticity and high-temperature aging performance should be verified separately.
3. Is the glass transition temperature of -147℃ equal to the usage temperature?
No, it is not. The glass transition temperature reflects the temperature point at which the molecular chains begin to lose their ability to move, but whether the product can maintain sealing, rebound and mechanical properties near this temperature point also needs to be verified through compression permanent deformation, low-temperature rebound and actual working conditions.
4. How to verify "constant elastic modulus and constant damping factor" in damping applications?
Tests should be conducted under the target temperature range, frequency and amplitude to observe whether there is significant attenuation, hardening or softening in the changes of elastic modulus and loss factor. The stability of the finished product's damping performance cannot be directly determined based on the raw material indicators.
5. Can it still be used after exceeding the 36-month validity period?
The data shows that the validity period of room temperature dry storage is 36 months. Whether it can be used after the expiration date should be rechecked for appearance, hardness, tensile strength, elongation, curing curve and low-temperature performance, and confirmed through small-scale tests.