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What substances will affect the hardness of TPS material?
The hardness of a material is often one of the first criteria considered when choosing a thermoplastic elastomer (TPE). Typically, there are three types of durometer used to express the hardness of TPE, especially styrene-based TPE, which are type A, D, and OO. We will show what substances in styrene-based TPE (hereinafter called “TPS”) affect the hardness of the material and how they change it.
Many substances can be used in TPS. Let us have a look at the list and how they have an impact on the material hardness.
1. Styrene Block Copolymers
Or it is called SBCs. They can be SBS, SEBS, SEPS, or more. The inherent hardness of those SBCs will make the foundation of the TPS compounds. They represent the elastomeric part of the TPS material and therefore it is generally soft. The hardness of SBCs, which relatively depends on the styrene content, ranges roughly from 30-98A Shore. The hardness will later be altered based on other substances added to the TPS compound formulation.
2. Paraffinic oil
The paraffinic oil is used as the process oil, the softening agent for SBCs. It is based on the SBCs selected to determine the PHR of the paraffinic oil. The more the paraffinic oil is used, the softer will be the TPS compounds. However, the dosage of paraffinic oil is not unlimited. Excess of oil or inappropriate percentage of paraffinic oil will lead to quality problems, such as oil exudation, weakening physical properties, excess MFR.
3. Thermoplastics/Masterbatch
Thermoplastics represent the hard phase of the TPS compounds. They contribute to engineering properties such as tensile strength, heat stability, and chemical resistance. Thermoplastics will increase the hardness of the TPS compounds. They can be PP, PE, PS, ABS, or more. Masterbatches will increase the hardness of TPS material as well, as they are thermoplastics based. Roughly the hardness will increase 5A Shore by adding 2.5% polypropylene. However, this is not always true when the hardness of the TPS material is at a higher range such as 85-95A shore. More percentage of polypropylene or thermoplastics are needed to increase the hardness by 5A when the TPS compounds get very hard.
4. Additives
Mostly the additives will not affect or have a very slight impact on the TPS material hardness. They are usually powder form and the dosage is very less in the formulation. They could be UV absorber, Antioxidant, lubricant, anti-blocking agent, pigment, stabilizer, processing aid, etc.
5. Filler
Calcium carbonate is the filler mostly used by TPS compounders. It originates from the limestone or marble. It will accelerate the cooling time of TPS compounds after melted and prevent the shrinkage of the material. By adding more calcium carbonate, the hardness will slightly increase.
Now we realize the varieties of substances that are used to make the TPS compounds. To achieve the desired material performance and hardness will require a perfect balance of all the ingredients. Phon Tech has decades of knowledge and experience in TPE formulation and compounding. We also have experts of polymer science to give you the solutions. We can suggest you a suitable material that perfectly matches your requirements. We can also custom make the TPS compounds for you. Do you feel excited about it and want to know how we materialize your vision? Do not hesitate to contact us.
Many substances can be used in TPS. Let us have a look at the list and how they have an impact on the material hardness.
1. Styrene Block Copolymers
Or it is called SBCs. They can be SBS, SEBS, SEPS, or more. The inherent hardness of those SBCs will make the foundation of the TPS compounds. They represent the elastomeric part of the TPS material and therefore it is generally soft. The hardness of SBCs, which relatively depends on the styrene content, ranges roughly from 30-98A Shore. The hardness will later be altered based on other substances added to the TPS compound formulation.
2. Paraffinic oil
The paraffinic oil is used as the process oil, the softening agent for SBCs. It is based on the SBCs selected to determine the PHR of the paraffinic oil. The more the paraffinic oil is used, the softer will be the TPS compounds. However, the dosage of paraffinic oil is not unlimited. Excess of oil or inappropriate percentage of paraffinic oil will lead to quality problems, such as oil exudation, weakening physical properties, excess MFR.
3. Thermoplastics/Masterbatch
Thermoplastics represent the hard phase of the TPS compounds. They contribute to engineering properties such as tensile strength, heat stability, and chemical resistance. Thermoplastics will increase the hardness of the TPS compounds. They can be PP, PE, PS, ABS, or more. Masterbatches will increase the hardness of TPS material as well, as they are thermoplastics based. Roughly the hardness will increase 5A Shore by adding 2.5% polypropylene. However, this is not always true when the hardness of the TPS material is at a higher range such as 85-95A shore. More percentage of polypropylene or thermoplastics are needed to increase the hardness by 5A when the TPS compounds get very hard.
4. Additives
Mostly the additives will not affect or have a very slight impact on the TPS material hardness. They are usually powder form and the dosage is very less in the formulation. They could be UV absorber, Antioxidant, lubricant, anti-blocking agent, pigment, stabilizer, processing aid, etc.
5. Filler
Calcium carbonate is the filler mostly used by TPS compounders. It originates from the limestone or marble. It will accelerate the cooling time of TPS compounds after melted and prevent the shrinkage of the material. By adding more calcium carbonate, the hardness will slightly increase.
Now we realize the varieties of substances that are used to make the TPS compounds. To achieve the desired material performance and hardness will require a perfect balance of all the ingredients. Phon Tech has decades of knowledge and experience in TPE formulation and compounding. We also have experts of polymer science to give you the solutions. We can suggest you a suitable material that perfectly matches your requirements. We can also custom make the TPS compounds for you. Do you feel excited about it and want to know how we materialize your vision? Do not hesitate to contact us.