Polytetramethylene Ether Glycol
Cas number: 【25190-06-1】
M D L: --MFCD00148879
Molecular formula: H(OCH2CH2CH2CH2)nOH
Alias: Polytetramethylene ether glycol α-Hydro-ω-hydroxypoly(oxy-1,4-butanediyl) Poly(1,4-butanediol)
Molecular formula:
Polytetrahydrofuran (PTMEG) properties: Polytetrahydrofuran is a homopolymer with hydroxyl groups at both ends obtained by cationic ring-opening polymerization of tetrahydrofuran monomers. This product is white waxy solid or colorless homogeneous transparent liquid. Insoluble in water and aliphatic hydrocarbons, easily soluble in alcohols, esters, ketones, aromatic hydrocarbons, and chlorinated hydrocarbons, and its solubility decreases with the increase of molecular weight. At room temperature, it is easy to absorb moisture in the air, and its water absorption decreases with the increase of molecular weight. Flammable at high temperatures.
Flash point: 109 °C
Melting point: 28-40°C
Polytetrahydrofuran (PTMEG) Density: 0.972
PTMEG type polyurethane has good low temperature resistance, hydrolysis resistance, salt water resistance and mold resistance. The disadvantage is that PTMEG is terminated by hydroxyl, so the hydrophilicity is increased, and it is easy to deliquescence; and because the carbon atom connected to the oxygen atom is easy to oxidize, it is easily affected by ultraviolet rays. PTMEG changes from a viscous liquid at room temperature to a waxy solid with increasing molecular weight. Its physical properties are mainly determined by molecular weight. Usually, the molecular weight of PTMEG is between 600 and 5000. The molecular weight of PTMEG that can be used for elastic materials and elastic fibers is between 1000 and 2000. The most widely used molecular weights are 1000 and 2000. At room temperature, PTMEG with low molecular weight is a colorless liquid, and PTMEG with high molecular weight is a white wax.
Quality Standard:
Hydroxyl value hydroxyl value (mgKOH/g) 54.7～57.5
Molecular weight 1950～2050
Moisture Water ≤0.015%
Acid value (mgKOH/g) ≤0.05
Chroma Color scale [(Pt-Co) number] ≤35
Stabilizer stabilizer 0.05-0.07% BHT
* Note: molecular weight = 56.1X2X1000/hydroxyl value
Storage: Hygroscopic and easy to oxidize, antioxidants should be added to the product to avoid direct exposure to the air.
Use PTMEG is one of the important raw materials for the production of spandex and polyurethane elastomers. It is used as the soft segment in polyurethane and can provide polyurethane products with good hydrolysis resistance, low temperature resistance and dynamic properties. It can also be used as the main raw material for elastomer products, resin for synthetic leather, and elastic fiber (spandex).
