Appearance: White/Yellow Flake
Package: 25kg/bag
Other name: PCE Monomer/ Polycarboxylic Ether Superplasticizer Monomer/ Polycarboxylate Ether Monomer/ Polycarboxylate Polyether Ponomer
Polycarboxylate superplasticizer monomer are the primary raw materials used in the production of polycarboxylate superplasticizers. They endow the superplasticizer mother liquids with a diverse range of constructional properties, including high water saving rate, high slump-retention capability, early strength gain, reduction in viscosity, anti-mud, alkali resistance, and frost prevention.
After nearly a century of development, the production process of the large monomers for polycarboxylate superplasticizers has matured. Polycarboxylate superplasticizer monomers are produced through a single process, known as ethoxylation.
This involves using small molecule unsaturated alcohols with different structures as initiators, mixing the catalyst with the initiator, displacing the air with nitrogen, and then introducing epoxyethane into the system for the ethoxylation reaction. After the reaction is complete, the mixture undergoes dehydration and filtration to ultimately obtain the polycarboxylate superplasticizer monomers.
Nowadays, the main types of polyether large monomers used in the preparation of polycarboxylate superplasticizers include MPEG (Methylallyl Polyethylene Glycol), APEG (Allyl Polyethylene Glycol), TPEG (Tetrapropenyl Polyoxyethylene Ether), VPEG (Vinyl Polyethylene Glycol) and HPEG (Methylallyl Polyoxyethylene Ether).
MPEG was one of the early large monomers used in the production of polycarboxylate superplasticizers. Its synthesis requires two steps: esterification and polymerization, making the process relatively complex.
Due to the incomplete esterification of MPEG, some large monomers remain in the product, which greatly affects the performance of the superplasticizer and can lead to unstable product quality.
EPEG (Ethylene glycol monovinyl polyethylene glycol ether) is synthesized by the opening polymerization of the initiator with ethylene oxide. The initiator used is ethylene glycol monovinyl ether, and the EPEG large monomers are commonly referred to as type 2+2 polyether large monomers.
TPEG (isopentenyl polyethylene glycol) and HPEG (methylallyl polyoxyethylene ether) have emerged, offering even greater advantages in terms of water reduction rate and slump retention for polycarboxylate superplasticizers. Due to their superior performance, these two types of large monomers have become the mainstream varieties in the Chinese market.
VPEG (4-hydroxybutyl vinyl polyoxyethylene ether) is obtained through ethoxylation using 4-hydroxybutyl vinyl ether as the initiator. It belongs to the type 2+4 hexanol and is structurally similar to EPEG, with the unsaturated double bond directly connected to the oxygen atom, exhibiting high reactivity.
This allows for low-temperature polymerization to produce polycarboxylate superplasticizers.
The development of APEG simplified the production process of polycarboxylate superplasticizers to some extent. The preparation of polycarboxylate superplasticizers using APEG only requires solution polymerization under normal pressure with co-polymer monomers.
However, APEG has poor polymerization properties, resulting in a high amount of monomer residue and instability in the performance of the produced superplasticizers. Currently, the production volume of APEG is decreasing year by year.
Polycarboxylate superplasticizer monomer have good water solubility and can dissolve in water and various organic solvents. They are essential raw materials for the production of new-type slump-maintaining polycarboxylate superplasticizers.
These monomers are produced using high-activity catalysts and special synthesis processes to create a product with a small molecular weight, low polyethylene glycol content, and high double bond retention rate. This significantly enhances the activation rate of multiple reactions, ultimately improving the conversion rate of the product.
The synthesized polycarboxylate superplasticizers exhibit good dispersion retention of cement particles and better adaptability to cement. They also offer advantages such as low concrete consumption, high water reduction rate, good strength enhancement effect, low shrinkage, good durability, strong corrosion resistance of reinforcing steel, and environmental friendliness.
Polycarboxylate superplasticizer monomers are white or light yellow flakes，non-toxic, odorless, and non-flammable, belonging to the category of green and environmentally friendly materials.
They can be handled and transported according to general chemical regulations and should be stored in a dry and well-ventilated area, protected from direct sunlight and rain. It is important to prevent from moisture, impurities, and other chemical solvents.
This product should be kept away from food, beverages, and tobacco. In case of fire, carbon dioxide, foam, and dry powder fire extinguishers can be used as fire-fighting measures. It should be used within the validity period.
The storage temperature should not exceed 40°C to avoid product caking due to high temperatures, which could affect the performance of the monomers.
Learn more about PCE monomer please contact us!
