a kind of non-ionic, multi-functional and environment-friendly solvent with low toxicity, film-forming property, hydrophilcity, weak ether scent, appropriate volatile speed, good chemical stability, excellent solubility, and high safety to human. It is classified as Non- HAP/NAP green solvent in the USA and EU. DMM is usually applied in water-based and curable coatings, chemicals like medicine and pesticide; widely used in cleanser, co-solvent, reaction solvent of organic synthesis, additive and moistening agent; used in electronic industry as cleaning agent by replacing N-methylpyrrolidone. In addition, it can be used to synthesize polyurethane.