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Material
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| TPE |
Usually consists of two materials, mainly by a hard nano-domain due to phase separation and dispersed in a soft rubber region. This region is mainly composed of molecules having rigidity and flexbility, and the bond between the two is usually a covalent bond. Therefore, the use of TPE temperature range is generally located between the glass transition temperature (Tg) and the melting point (Tm). Another type of rubber and plastic glue TPO or cross-linked TPO (TPV). The above-mentioned soft region is usually composed of elastic rubber and dispersed in the plastic hard substrate (Matrix), the two regions are composed of different high molecular weight, and the covalent bond is different.
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| TPS |
Closest to the rubber properties, because NR (Natural Rubber) has the characteristics of stress-induced crystallization, is one of the few crystalline rubber materials, so the stress in addition to providing molecular deformation, but also consume a part of the "melting" formed by the crystal, so the general amorphous SBR strength is much higher (harder). Hydrogenated SBS (SEBS) has better heat resistance, oxidation resistance and weather resistance than SBS, so its application is more extensive, including wire and cable coating, connectors, plug coating, medical tubing, automotive and building window strips, plastic modification, etc., but poor chemical resistance and temperature resistance.
Temperature: -70 ~ 100°C
Hardness shore A: 40 ~ 55 A
Ratio: 0.9 ~ 1.1
Characteristics: water resistance, polarity resistance organic solvent. Not resistant to oil, fuel and non-polar organic solvents
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| TPO |
Consists of PP / EPDM Compound, with excellent flexibility and impact resistance, and less toxic when burned, so for the PVC wire market, caused an impact, but its biggest drawback is the chemical resistance and temperature resistance is not enough.
Temperature: -60 ~ 100°C
Hardness shore: 60A ~ 75D
Ratio: 0.85 ~ 1.0
Characteristics: resistant to polar solutions (such as water, aqueous solutions, ethanol, etc.)
Not resistant to polar solutions (hydrocarbons, halocarbons) will occur expansion.
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| TPV |
Consists of PP / EPDM Compound and then through dynamic vulcanization, with highly cross-linked rubber dispersed phase, and there is a dynamic vulcanization operation reaction, so its heat resistance is higher than the general uncrosslinked adhesive, with a lower dielectric constant, especially the anti-permanent deformation properties, is the best of all TPE, after the improved TPV, has been able to PA, PC, PC / ABS, ABS over-molding.
Temperature: -60 ~ 135 °C
Hardness shore: 35A ~ 50D
Ratio: 0.85 ~ 1.0
Characteristics: resistant to polar solutions (such as water, aqueous solutions, ethanol, etc.), oil resistance, anti-ink, not resistant to polar solutions (hydrocarbons, halocarbons) will occur swelling
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| TPU |
Due to the different materials of the soft segment, divided into polyester (Polyeaster Type) & polyether (Polyether Type). The main difference is that the polyester TPU soft segment is more resistant to non-polar solvents, has better physical properties (tear strength, high wear resistance, toughness), weather resistance, oxidation resistance, oil resistance; and polyether soft segment is more resistant to hydrolysis, anti-mildew antibacterial stability, with greater resilience, because of low hysteresis, low heat accumulation and low temperature characteristics. The main key is the relationship between the polyether chain. TPU has good hydrolysis resistance and better elasticity, especially with PC, PC / ABS, ABS over-molding. The above two types of materials are excellent biocompatibility (Biocompatibility), so in the biomedical use of all TPE materials in the most widely used.
Temperature: -70 ~ 100 °C
Hardness shore: 40A ~ 74D
Ratio: 1.1 ~ 1.3
Characteristics: oil, fuel, oil, general fatty compounds are excellent, aromatic anti-chemical resistance is slightly worse. Not resistant to polar organic matter, such as DMS (Dimethyl Sulphoxide), DMF (Dimethyl Formamide), because this type of solvent will erode TPU, but it is a good solvent, TPU and TPEE as water resistance, resistance to water-soluble Solvent (except at very high and very low PH values)
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| TPEE |
In terms of mechanical properties, the hardness is higher than that of the general TPE, and the elastic range is wider. Generally speaking, TPEE has better stability, oil resistance, fatigue resistance, and has the advantages of strength, elasticity and dynamic properties. It belongs to the engineering plastic TPE.
Temperature: -40 ~ 150 °C
Hardness shore: 30D ~ 80D
Ratio: 1.13 ~ 1.25
Characteristics: excellent resistance to bending fatigue and creep, excellent tensile and compressive
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| TPA |
Temperature: -55 ~ 55 °C
Hardness shore: 25D ~ 70D
Ratio: 0.96 ~ 1.04
Characteristics: low moisture absorption, low temperature impact and resistance to bending fatigue and creep, excellent tensile and compressive, Wear resistance and excellent resistance to chemical properties, in the TPE is a higher level of mechanical properties and heat resistance is excellent, but in the low temperature characteristics is not as good as TPU, but in the wear resistance, almost to TPU, due to low moisture absorption characteristics, almost no need to dry processing, so in the stability of the finished product, has excellent performance, often used in high heat resistance, resilience and wear resistance requirements of the pipeline.
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| MPPO |
MPPO (modified polyphenylene ether) goods are made of high impact polystyrene (HIPS). Excellent processability, small molding shrinkage, good dimensional stability, low water absorption, and good electrical and thermal properties, heat water is not easy to decompose, acid and alkali resistance, low density, no need to use halogen flame retardant to achieve UL flame retardant standard, widely used in household appliances, electronics industry and automotive industry.
The advantages are as follows:
1. Dielectric properties is the best of engineering plastics
MPPO resin molecular structure without strong polar groups, in a wide range of working temperature and frequency to maintain good electrical properties. Its dielectric constant is the smallest of the five engineering plastics, almost unaffected by temperature, humidity and frequency. Its volume resistivity (up to 1017) is the highest in engineering plastics.
2. Good mechanical properties and thermal properties
PPO molecular bonds, containing a large number of aromatic ring structure, molecular bond rigidity. The resin has high mechanical strength, excellent creep resistance and little influence on temperature change. Polyphenylene ether has higher heat resistance, with the increase of PPO content, the heat deformation temperature increases, and vice versa. The change of glass transition temperature and softening point temperature is also the same. PPO and high impact polystyrene modified with polybutadiene rubber (SBR) can increase toughness and improve impact strength.
3. Excellent hydrolysis resistance
MPPO is a non-crystalline resin with high glass transition temperature. It has very good hydrolysis resistance and is the lowest water absorption material in the five engineering plastics.
4. Excellent flame retardancy
The oxygen consumption index (LOI) of polyphenylene ether is 29, which is self-extinguishing material (94 V0), while the oxygen consumption index (LOI) of high impact polystyrene (PE) is 17, which is flammable material. When the two are combined, they have moderate flammability (94 V2). When producing flame retardant MPPO, it is not necessary to add halogen flame retardant. Adding phosphorus flame retardant can achieve UL-94V0 flame retardant grade and reduce environmental pollution.
5. Low shrinkage and good dimensional stability
MPPO is a non-crystalline thermoplastic plastic with small molding shrinkage, almost no strain and warping caused by crystallization, and size change (post-shrinkage) caused by recrystallization after molding.
6. Non-toxic and low density
MPPO has low density, density of 1.06g/cm3, is the lightest of the five engineering plastics, and non-toxic, can pass the United States Food and Drug Administration (PDA) and the National Health Foundation (NSF) certification, can be used to manufacture medical and food equipment.
The disadvantages are as follows:
1. Poor resistance to organic solvents such as aliphatic, halogenated aliphatic and aromatic polyphenylene ethers and modified polyphenylene ethers are basically non-corrosive to acids, alkalis and detergents; under pressure, mineral oil and ketones, esters Solvents and 85°C concentrated sulfuric acid will produce stress and crack; organic solvents such as aliphatic, halogenated aliphatic and aromatic polyphenylene ethers and modified polyphenylene ethers will cause polyphenylene ethers and modified polyphenylene ethers to swell and even dissolve.
2. Poor light resistance (UV)
The weakness of polyphenylene ether is poor light resistance. Long-term use under sunlight or fluorescent lamps will cause yellowing. The reason is that ultraviolet rays can cause aromatic ether bonds to split. However, GE company adds 1% of ultraviolet absorber to improve the light resistance of MPPO.
Temperature: -4 ~ 120°C
Hardness shore A: 70~93A
Ratio: 0.92 ~ 1.1
Characteristics: FDA, NSF certification, hydrolysis resistance, acid and alkali resistance, halogen-free flame retardant. Not resistant to aliphatic, halogenated aliphatic and aromatic organic solvents.
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