Polyether Polyol Vs Polyester Polyol
Polyester polyols, which are organic substances, are usually formed by condensation (or transesterification) of an organic dicarboxylic acid (anhydride or ester) with a polyol (including a diol) or by polymerization of a lactone with a polyol. The dibasic acid is phthalic acid or phthalic anhydride or an ester thereof, adipic acid, halogenated phthalic acid or the like. The polyhydric alcohol is ethylene glycol, propylene glycol, diethylene glycol, trimethylolpropane, pentaerythritol or the like. Different types of polyester polyols have different properties due to different types or different preparation processes. Several indicators that are important for polyester polyols are hydroxyl number, acid value, moisture, viscosity, molecular weight, density, and color. Characteristics and uses of polyester polyols: Polyester-based polyurethane contains a large number of polar groups such as ester groups and amino groups in the molecule, and has strong cohesive strength and adhesion, and has high strength and wear resistance.
Polyether polyol (referred to as polyether) is composed of an initiator (active hydrogen group-containing compound) and ethylene oxide (EO), propylene oxide (PO), butylene oxide (BO), etc. in the presence of a catalyst. It is obtained by polyaddition reaction. The largest yield of polyether is glycerol (glycerol) as the initiator and epoxide (usually PO and EO). Various general-purpose polyether polyols are produced by changing the feeding mode of PO and EO (mixing plus or separately adding), the ratio of addition, the order of addition, and the like.
Related Products Wiki
- January 31, 2018November 15-17, 2017Xiamen International Convention and Exhibition CenterAPI China is China's leading exhibition for the pharmaceutical manufacturing sector covering the complete spectrum of products ...view
- January 30, 2018As an annual welfare practice, NCMC 2017’s 5 day company tour from Nanjing to Gansu started in Sept. 1, 2017. The main purpose is to enrich corporate culture, relieve work stress, enchance group sens...view
- March 13, 20191.Chemical cleaningAs an organic acid, glycolic acid has a good cleaning function for certain metal scales. Since glycolic acid does not contain chloride ions, it is extremely corrosive to equipment m...view
- January 29, 2019June 20th-21th@ Cologne, GermanyAs one of the largest fine and speciality chemical exhibition in the world, Chemspec 2018 was staged during June 20th-21st 2018 at Cologne, Germany. This year's exhibit...view
- January 30, 2018September 21-23, 2017 Beijing·China International Exhibition CenterAs the most professional, authoritative and largest international exhibition in China lubricant industry, China International Lubr...view
- January 29, 2019Before the summer heat arrives at Nanjing, 2018 NCMC sports meeting is held on 27th May with the purpose of enriching the amateur life of employees as well as enhancing team cooperation.This sports me...view