What type of rubber is this?
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When my friend was visiting a company’s factory, he saw the company’s staff introduce a type of rubber. They took out a small container each containing a blue liquid at low temperature and a white liquid from the refrigerator, mixed them in a molding mold. After mixing, the mold was left at room temperature for 24 hours or baked in an oven for a certain period of time; as a result, the liquids turned into a shaped rubber in the mold, with a light blue color. The mold is in the shape of a wristband, and the rubber produced is similar to the Nike wristbands used for playing basketball. I would like to ask everyone, what type of rubber is this? Furthermore, is this property the thermoplasticity of rubber? If so, then which types of rubber generally possess such thermoplasticity? If not, then what is this characteristic?
Liquid rubber. After molding, it has a very good feel and elasticity
So, do you know what monomers are used to synthesize this liquid rubber?
According to the poster’s description, it should be room-temperature vulcanizing two-component liquid silicone rubber. Blue is due to the addition of pigments, while white is caused by the silica reinforcement agent.
It should be shaped after reacting; it’s hard to say whether it’s thermoplastic or not.
This post was last edited by QXZ-1966 on 2009-5-1 at 18:13. Previously, for work purposes, I downloaded and organized similar posts from the Internet. I’m sending it to you to show – recently, Laur Silicon Rubber Company presented a new generation of liquid silicone rubber. This material utilizes the state-of-the-art controlled vulcanization technology (EC), addressing some of the issues associated with current two-component liquid silicone rubbers (LSR). This material can be supplied after being fully combined as a single system (IP). Although this material is still in the early stages of commercialization, it has broad application prospects due to the following advantages: 1. Perfect compatibility – no mixing required ； 2. No substances with improper proportions ； 3. No need to clean the mixing equipment ； 4. No material loss during the cleaning process ； 5. Excellent physical properties (tensile strength, elongation at break, tear strength, thermal aging resistance, compressive set) ； 6. Long storage life ； 7. Short vulcanization cycle ； 8. Complies with FDA standards ； 9 color adjustment ； 10. Different hardness. Degrees can be mixed. Although it is often claimed that liquid silicone rubber is well mixed, this is not actually the case. Typical liquid silicone rubber consists of two components, A and B, which need to be mixed before use. At room temperature, the storage life of the mixture is no more than 3 days. In most cases, when color requirements are present, a colorant must be added in advance. This new stable vulcanization system can be supplied as a single component, eliminating the need for further mixing. This means that it is only necessary to pour the raw materials directly into the mold. Since two-component liquid silicone rubber needs to be mixed before use, issues of improper local mixing ratios are inevitable. In two-component systems, if the pump does not operate properly, substances with an improper ratio will be produced. Uneven mixing can affect the vulcanization cycle and physical properties of rubber. The storage life of two-component adhesive is no more than 3 days. Therefore, when the mixing equipment is not in use for a long time, it must be cleaned thoroughly. If only one of components A and B is cleaned, it will result in an improper mixing ratio when the equipment is used again, leading to waste of materials. Material systems utilizing the new stable vulcanization technology have a long storage life; therefore, there is no need to clean or sanitize the mixing equipment when it is not in use for extended periods of time. As shown in Table 1-3, this new single-component silicone rubber exhibits similar properties to the existing two-component liquid silicone rubber. The viscosity of this new material is not listed in the table; in reality, it is similar to that of two-component liquid silicone rubber. Table 1 Comparison of Physical Properties of 40°C Two-Component and Single-Component Liquid Silicone Rubbers
Physical Properties: Hardness, Tensile Strength (MPa), Elongation at Break (%), Tear Strength (kN/m)
Plate Vulcanization, 10 min, 171°C: 1P, 40°C – 38.3, 6.9, 536, 55.5
LSR#1A+B, 1:1 – 39.9, 9.0, 573, 19.3
LSR#2A+B, 1:1 – 38.1, 9.2, 631, 60.1
LSR#3A+B, 1:1 – 44.0, 9.0, 585, 40.1
Two-Stage Vulcanization, 4 h, 200°C: 1P, 40°C – 40.1, 8.1, 572, 32.6
LSR#1A+B, 1:1 – 40.2, 9.2, 533, 23.1
LSR#2A+B, 1:1 – 41.4, 8.0, 516, 36.1
LSR#3A+B, 1:1 – 46.2, 9.3, 528, 40.5
Table 2 Physical Properties of Silicone Rubbers After Thermal Aging
Physical Properties (225°C × 70 h): Hardness, Tensile Strength (MPa), Elongation at Break (%), Tear Strength (kN/m)
Plate Vulcanization, 10 min, 171°C: 1P, 40°C – 46.9, 8.2, 412, 33.8
LSR#1A+B, 1:1 – 40.6, 6.9, 374, 22.8
LSR#2A+B, 1:1 – 45.1, 5.3, 236, 34.3
LSR#3A+B, 1:1 – 46.7, 6.7, 318, 28.5
Two-Stage Vulcanization, 4 h, 200°C: 1P, 40°C – 46.2, 8.3, 410, 33.4
LSR#1A+B, 1:1 – 40.9, 6.9, 362, 20.3
LSR#2A+B, 1:1 – 45.7, 4.8, 231, 34.0
LSR#3A+B, 1:1 – 47.1, 7.1, 342, 28.0
Table 3 Compression Set After Plate Vulcanization and Two-Stage Vulcanization
Compression Set (177°C × 22 h), %: 1P, 40°C – 24, 18
LSR#1A+B, 1:1 – 56, 38
LSR#2A+B, 1:1 – 46, 11
LSR#3A+B, 1:1 – 16, 11
Tests were conducted on this new material after it was stored in a warehouse for 6 months. Compared to 6 months ago, the vulcanization curve and physical properties of this single-component liquid silicone rubber after 6 months of storage showed almost no changes (Tables 4 and Figures 1 are omitted). The stability of this new system was once again demonstrated through a test in which the sample was stored at 71°C for one week. Similarly, neither the performance nor the vulcanization curves changed (Tables 5 and Figure 2 are omitted). Table 4 Physical properties before and after storage testing: Hardness, tensile strength in MPa, elongation at break in %, tear strength in kN/m. Values before testing: 9.2382; after 6 months: 63.79 and 0.34449 and 0.0. Table 5 Physical properties before and after heat stability testing: Hardness, tensile strength in MPa, elongation at break in %, tear strength in kN/m. Values before testing: 9.2399; after 6 months: 56.39 and 0.640844 and 0.5. The good stability provided by the controlled vulcanization technique also benefits the scorch resistance, enhancing the safety of the vulcanization process during longer molding times. This is very helpful in cases where mold design and mold installation are difficult. The vulcanization time of one-component liquid silicone rubber is longer than that of two-component systems, mainly due to its longer scorch time. The vulcanization rate of the steady vulcanization system is not much worse than that of the two-component system. Figure 3 (omitted) compares the vulcanization curves of single-component silicone rubber and three different two-component silicone rubbers. The materials can meet the requirements of the U.S. Food and Drug Administration (FDA). After two-stage vulcanization, the sample rubber compound is tested in accordance with CFR171.2600. The sample passed the strict tests for products that are exposed to food over long periods of time or repeatedly. Due to its long storage life, one-component silicone rubber can be supplied in a fully compounded form. This reduces the possibility of improper mixing ratios. One-component silicone rubber can be supplied in a colored form, eliminating the need to mix colorants before molding, as is necessary for two-component silicone rubber. Therefore, a simple pump can replace the existing mixing and metering equipment. For manufacturers, having mixed-metering equipment allows them to predict the intermediate hardness when mixing silicon rubbers of different hardnesses, which enables small users to minimize inventory as much as possible. If a certain hardness is required, the time is set in advance through calculation, and then two pumps are activated to draw out the raw materials of different hardnesses from the tanks respectively. For manufacturers who do not wish to adjust hardness through mixing, it is possible to conduct a full set of material tests without turning on the mixing equipment, thus allowing testing to be completed prior to production. The new steady vulcanization technology holds the potential to open up new markets for liquid silicone rubber. A short-term investment can be made in this new single-component material, eliminating the need to purchase metering and mixing equipment. Its stable and safe vulcanization properties are also expected to open up new markets for it.
Physical Properties: Hardness, Tensile Strength (MPa), Elongation at Break (%), Tear Strength (kN/m)
Plate Vulcanization, 10 min, 171°C: 1P, 40°C – 38.3, 6.9, 536, 55.5
LSR#1A+B, 1:1 – 39.9, 9.0, 573, 19.3
LSR#2A+B, 1:1 – 38.1, 9.2, 631, 60.1
LSR#3A+B, 1:1 – 44.0, 9.0, 585, 40.1
Two-Stage Vulcanization, 4 h, 200°C: 1P, 40°C – 40.1, 8.1, 572, 32.6
LSR#1A+B, 1:1 – 40.2, 9.2, 533, 23.1
LSR#2A+B, 1:1 – 41.4, 8.0, 516, 36.1
LSR#3A+B, 1:1 – 46.2, 9.3, 528, 40.5
Table 2 Physical Properties of Silicone Rubbers After Thermal Aging
Physical Properties (225°C × 70 h): Hardness, Tensile Strength (MPa), Elongation at Break (%), Tear Strength (kN/m)
Plate Vulcanization, 10 min, 171°C: 1P, 40°C – 46.9, 8.2, 412, 33.8
LSR#1A+B, 1:1 – 40.6, 6.9, 374, 22.8
LSR#2A+B, 1:1 – 45.1, 5.3, 236, 34.3
LSR#3A+B, 1:1 – 46.7, 6.7, 318, 28.5
Two-Stage Vulcanization, 4 h, 200°C: 1P, 40°C – 46.2, 8.3, 410, 33.4
LSR#1A+B, 1:1 – 40.9, 6.9, 362, 20.3
LSR#2A+B, 1:1 – 45.7, 4.8, 231, 34.0
LSR#3A+B, 1:1 – 47.1, 7.1, 342, 28.0
Table 3 Compression Set After Plate Vulcanization and Two-Stage Vulcanization
Compression Set (177°C × 22 h), %: 1P, 40°C – 24, 18
LSR#1A+B, 1:1 – 56, 38
LSR#2A+B, 1:1 – 46, 11
LSR#3A+B, 1:1 – 16, 11
Tests were conducted on this new material after it was stored in a warehouse for 6 months. Compared to 6 months ago, the vulcanization curve and physical properties of this single-component liquid silicone rubber after 6 months of storage showed almost no changes (Tables 4 and Figures 1 are omitted). The stability of this new system was once again demonstrated through a test in which the sample was stored at 71°C for one week. Similarly, neither the performance nor the vulcanization curves changed (Tables 5 and Figure 2 are omitted). Table 4 Physical properties before and after storage testing: Hardness, tensile strength in MPa, elongation at break in %, tear strength in kN/m. Values before testing: 9.2382; after 6 months: 63.79 and 0.34449 and 0.0. Table 5 Physical properties before and after heat stability testing: Hardness, tensile strength in MPa, elongation at break in %, tear strength in kN/m. Values before testing: 9.2399; after 6 months: 56.39 and 0.640844 and 0.5. The good stability provided by the controlled vulcanization technique also benefits the scorch resistance, enhancing the safety of the vulcanization process during longer molding times. This is very helpful in cases where mold design and mold installation are difficult. The vulcanization time of one-component liquid silicone rubber is longer than that of two-component systems, mainly due to its longer scorch time. The vulcanization rate of the steady vulcanization system is not much worse than that of the two-component system. Figure 3 (omitted) compares the vulcanization curves of single-component silicone rubber and three different two-component silicone rubbers. The materials can meet the requirements of the U.S. Food and Drug Administration (FDA). After two-stage vulcanization, the sample rubber compound is tested in accordance with CFR171.2600. The sample passed the strict tests for products that are exposed to food over long periods of time or repeatedly. Due to its long storage life, one-component silicone rubber can be supplied in a fully compounded form. This reduces the possibility of improper mixing ratios. One-component silicone rubber can be supplied in a colored form, eliminating the need to mix colorants before molding, as is necessary for two-component silicone rubber. Therefore, a simple pump can replace the existing mixing and metering equipment. For manufacturers, having mixed-metering equipment allows them to predict the intermediate hardness when mixing silicon rubbers of different hardnesses, which enables small users to minimize inventory as much as possible. If a certain hardness is required, the time is set in advance through calculation, and then two pumps are activated to draw out the raw materials of different hardnesses from the tanks respectively. For manufacturers who do not wish to adjust hardness through mixing, it is possible to conduct a full set of material tests without turning on the mixing equipment, thus allowing testing to be completed prior to production. The new steady vulcanization technology holds the potential to open up new markets for liquid silicone rubber. A short-term investment can be made in this new single-component material, eliminating the need to purchase metering and mixing equipment. Its stable and safe vulcanization properties are also expected to open up new markets for it.
The person upstairs is very professional; thank you! 8# QXZ-1966