1-Methoxy-2-Propanol CAS 107-98-2 Propylene Glycol Methyl Ether

Propylene Glycol Methyl Ether Acetate (PMA) is an important high-grade solvent with strong solubility for both polar and non-polar substances. Its solubility is much higher than that of general solvents, propylene glycol ethers and ethylene glycol ethers, and it has good miscibility with water. PMA can be used as a solvent for cellulose, polymers, rubber and natural macromolecules. Because propylene glycol methyl ether acetate has the characteristics of high solubility, good environmental protection performance, excellent thermal stability, and small viscosity change, it is widely used in coatings, inks, printing and dyeing, pesticides and other fields, and is replacing the more toxic glycol ethers. and its ester solvents. At present, propylene glycol methyl ether (PM) and acetate are mainly used to synthesize PMA in industry, and traditional concentrated sulfuric acid catalyst is used in the synthesis process. This process has the problems of serious corrosion of equipment by concentrated sulfuric acid, complicated post-treatment process of reactants, generation of waste residue and waste liquid to pollute the environment, low product yield, high production cost and poor efficiency.

CN200510039023.4 provides a new technology that can avoid above-mentioned defects, pollution-free and low consumption for the synthesis of propylene glycol methyl ether acetate (PMA). In the present invention, propylene glycol methyl ether, acetic acid and toluene are firstly esterified under the catalysis of p-toluenesulfonic acid, and then the excess propylene glycol methyl ether is recovered through a light-removing tower and then rectified to obtain propylene glycol methyl ether acetate. In the present invention, the development and research of a new type of catalyst is carried out in view of the problems that the traditional sulfuric acid catalyst used in the synthesis of PMA has the problems of polluting the environment and affecting the products. As a catalyst, p-toluenesulfonic acid has high catalytic activity, good selectivity and high product yield for synthesizing PMA; it is non-corrosive to the existing PMA production equipment with a material of 316L; the reactants do not need to be neutralized and desalted, and there is no waste residue, The waste liquid is discharged, and the catalyst can be recycled. The successful development of the catalyst makes the production of PMA an advanced green chemistry, which greatly simplifies the post-treatment process of PMA production and greatly improves the economic benefits of PMA production. The present invention has the advantages that traditional catalysts cannot be replaced in terms of improving the selectivity and conversion rate of the reaction process, economy, optimizing the design of the reaction process, simplifying the post-processing process and recycling of non-product components, and showing good industrial performance. application prospects.

The technical scheme provided by CN200910168507.7 of the present invention is: a preparation method of electronic grade propylene glycol methyl ether acetate, which uses propylene glycol methyl ether and acetic acid as raw materials, and uses a strong acid cation resin catalyst to carry out esterification reaction. Preferably, the preparation method comprises the following steps:

1. Mix propylene glycol methyl ether and acetic acid, enter the first fixed bed to carry out esterification reaction, the reaction temperature is 60 ℃～100 ℃, and this fixed bed is filled with strong acid cation resin catalyst;
2. Carry out dehydration treatment to the material after esterification, and described dehydration treatment process is to add cyclohexane or toluene in the product, stir, through distillation, condensation, leave standstill layering, remove water phase layer;
3. The material after dehydration treatment is deionized to be electronic grade propylene glycol methyl ether acetate. The metal ion content of the electronic grade propylene glycol methyl ether acetate obtained by the invention is greatly reduced, and the metal ion is reduced from 250 to 1000 PPb to below 5 PPb. The conversion rate of propylene glycol methyl ether is more than 99.5%, and the conversion rate is high.

The invention realizes the continuous production of electronic grade propylene glycol methyl ether acetate, has simple operation mode, significantly improves production efficiency and reduces production cost. And it can reduce the generation of solid pollutants and waste liquid, reduce the corrosion of equipment, and meet the requirements of green chemistry in the 21st century.

Organic ester compounds are good solvents and are widely used in the synthetic resin industry, such as coatings, inks, adhesives and cleaning agents. CN94105197.8 React propylene glycol methyl ether (hereinafter referred to as PGM) with isobutyric acid or n-butyric acid in the presence of an acidic catalyst to generate propylene glycol methyl ether isobutyl ester (hereinafter referred to as PMIB) or propylene glycol methyl ether n-butyl ester (hereinafter referred to as PMB) .