What is the difference between high transparent TPE and natural TPE?
Time：2020-06-04Hits：1944
Speaking of the difference between transparent TPE and TPR, in fact, in general, the difference between the two is not big, because they belong to the same category of products, so we have to look at them from the top of the breakdown to know the subtle gap between the two. Here is an analysis of the gap between them.
Transparent TPE, specifically thermoplastic elastomer, while TPR is translated from English, strictly called thermoplastic rubber, which is the most basic difference. TPE is generally formed from SEBS's basic materials, while TPR is modified from SBS's basic materials. Therefore, the choice and use of raw materials in production are different. Then let's also learn about the differences between SEBS and SBS in their raw materials.
SEBS is the product of SBS after hydrogenation. SEBS has saturated molecular state structure. Such molecular structure leads to different characteristics of SEBS. It has the characteristics of aging resistance, yellowing resistance and other characteristics necessary for the production of transparent TPE, and contributes to the excellent characteristics of high temperature resistance and corrosion resistance. To produce transparent TPE. Therefore, transparent TPE is superior to TPR in industrial use, as well as in appearance. And TPR has its desirable quality characteristics, for example, TPR has strong light reflection, because TPR particles are relatively bright.
Regarding the transparency of elastomer TPE and TPR, the transparency of TPE and TPR materials will be affected due to the differences in the specific brand specifications and the distribution ratio of each component of the matching system.
1. Influence of raw materials on transparency
(1) Place of origin: refers to SEBS substrates from various places of origin, TPE processed by blending, and the transparency is ranked in order. In recent years, Yuehua SEBS has undergone desalting treatment to improve the transparency of TPE blended products.
(2) Molecular weight: For brands from the same place of origin, the transparency of TPE blended with SEBS tends to decrease as the molecular weight of SEBS increases.
(3) Degree of branching: For SEBS with the same molecular weight from the same origin, the higher the degree of branching of the general molecular chain, the lower the transparency of the processed TPE.
2. Influence of Oil Products and Additives
(1) degree of hydrogenation: selecting oils with high degree of hydrogenation (e.g. three times hydrogenation) is beneficial to transparency and yellowing resistance of TPE materials.
(2) Addition: The greater the proportion of oil in the blending system, the better the transparency (lower the hardness of the material) of TPE finally synthesized by the blending system.
3. Influence of Plastic Resin Additives
In order to improve the strength of TPE and TPR materials, a certain amount of PS or PP plastic is usually added to the blending system. In order to keep the transparency of the materials as much as possible, on the one hand, the specification and origin brand of PS and PP need to be considered. On the other hand, the addition amount of plastic is also an important factor affecting the transparency of TPE and TPR. Generally, with the increase of plastic (PS,PP), the hardness of TPE and TPR increases, and the transparency of the material gradually decreases. Moreover, the transparency of TPE of SEBS substrate decreases more obviously than that of SBS substrate.
The transparency of TPE and TPR materials and its influencing factors are analyzed from the aspect of raw material blending. To obtain TPE and TPR with high transparency, engineers undoubtedly need to consider the above factors. For the purchaser of TPE and TPR materials, if you want to process TPE and TPR products with high transparency, you should not only select TPE and TPR brands with high transparency, but also pay attention to selecting appropriate processing and molding temperature.
Highly transparent TPE (based on SEBS substrate): hardness 0 ~ 70A;
High transparent TPR (based on SBS substrate): hardness 10~90A；;
•TPE|TPR High Transparent Material Suggested Injection Molding Temperature 150~200℃, Shrinkage 1.6~2.0%.
•TPE|TPR High Transparent Material Main Applications: Soft Plastic Toys, Adult Products, Medical Devices such as Medical Catheter Infusion Sets, Mobile Phone Protective Covers, Electronic Products Accessories Encapsulation, etc.
High transparent material, the product can reach high permeability, high ductility, excellent rebound resilience, high tensile property, good fluidity, good yellowing resistance, can replace silica gel /PVC material, has no odor, is nontoxic and environment-friendly, and meets the environmental detection standards of ROHS,REACH,PAHS,EN71 and the like.
4. Solution to blocking problem of transparent TPE
TPE|TPR transparent material has a common problem: caking! How to solve the caking problem of transparent TPE?
(1) Control the temperature, transparent TPE below 0 degree, even if treated with additives, will still agglomerate after more than 3 months. Generally below 40 degrees there is a tendency to agglomerate.
(2) Transparent TPE is made underwater. The special anti-sticking agent for TPE is added into the water tank to prevent the transparent TPE from sticking together. Note: The proportion added depends on the size of the pool.
(3) If the product is caked, add some slip agent.
(4) If the transparent TPE is caked in the packaging bag, first look at its shape. Cylindrical TPE is easier to cake. It is better to make it round or oval or add some anti-caking agent during granulation.
德创化工 (edit：dechuang)
