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English name: 2,2-Bis (hydroxymethyl) butyric acid
English synonyms: 2,2-Dimethylolbutyric Acid; 2,2-Bis (Hydroxymethyl) Butyric Acid; 2,2-Bis (Hydroxymethyl) -N-Butyric Acid; 2,2-Bis (Hydroxymethyl) Butanoic Acid; Dimethylolbutanoicacid (Dmba) ; Dimethylolbutanoicacid;
CAS number: 10097-02-6
EINECS number: 424-090-1
Molecular formula: C6H12O4
Molecular weight: 148.16
Physical and chemical properties: white crystals, melting point 108-115 ° C, soluble in water, methanol, acetone, etc.

2,2-Dimethylol butyric acid (chain extender hydrophilic agent DMBA) Usage: DMBA is a neopentyl carboxylic acid with two active hydroxymethyl groups, so it can be used as a synthetic aqueous polymer system , Can be widely used in water-soluble polyurethane, polyester, epoxy resin, etc. DMBA has better solubility than DMPA in different solvents, so it can greatly improve the work efficiency.

DMBA is regarded as a new generation of environmentally friendly chain extenders and internal emulsifiers for waterborne polyurethanes. The production of waterborne polyurethane adhesives does not require the use of organic solvents and has zero organic residues. There is no problem of using DMPA with high melting point, slow dissolution, long reaction time, high energy consumption, poor product performance, the need to add organic solvents, and large solvent residues. It can also be used to manufacture adhesives such as water-based epoxy resin and polyester. At present, water-based polyurethane, water-based resin, water-based adhesive, water-based paint and other water-based products are multi-purpose modification additives (hydrophilic chain extender) .As a monomer, during the modification process, dimethylol butyric acid (DMBA) does not need to add any Organic solvent (replaced by water), the production process is simpler, and the performance is stable. Among them, dimethylhydroxypropionic acid (DMPA) makes its application in the field of water more common due to its superior cost performance!

Use:

1. In the production of waterborne polyurethane / polyester system coatings, adhesives and leather finishing.

2. Paint additives, used in water-soluble polyurethane, epoxy resin, adhesives, etc.

3. DMBA is a neopentyl carboxyl group with two active hydroxymethyl groups, so it can be used as a synthetic water-based polymer system, and can be widely used in water-soluble polyurethane, polyester, epoxy resin, etc. DMBA has better solubility than DMPA in different solvents, so the work efficiency can be greatly improved.

Compared with DMBA and DMPA, DMBA has the following obvious advantages:

(1). DMBA has better solubility in organic solvents. The following table shows the solubility data of DMBA and DMPA in different solvents at different temperatures; (unit g / 100g solvent)

2,2-Dimethylol butyric acid (chain extender hydrophilic agent DMBA) has a solubility in water of 48% and DMPA of 12%. At the same time, DMBA has a low melting point of 108 ℃ ～ 115 ℃;

Because DMBA has excellent solubility and low melting point, it does not require solvent or add less solvent in the process of synthesizing aqueous polyurethane emulsion.

(2). High reaction rate, fast reaction speed and low reaction temperature. Synthetic polyurethane prepolymer has a short reaction time, generally 50-60 minutes, while DMPA requires 150-180 minutes. This is because there is one more methylene group in the DMBA structure than DMPA, which increases the distance between the carboxyl group and the methylene group, and reduces the steric hindrance of the carboxyl group and the isocyanate, thereby increasing the reaction rate.

(3). It is used in waterborne polyurethane emulsion with finer particle size and narrow distribution, excellent film performance and high gloss.

2,2-Dimethylolbutyric acid (chain extender hydrophilic agent DMBA) Packing: 25kg / bag Cardboard drum or carton, lined with aluminum-plastic film bag. Store in a warehouse that is ventilated, dry, away from fire, and meets fire protection requirements.