What is Hydroxyethyl Methacrylate
Hydroxyethyl methacrylate (HEMA) is an organic, colorless, transparent, and easy-flowing liquid. As a non-toxic, harmless, and widely used reagent, it is usually used in soft lens materials, lens materials, or as a monomer for the preparation of dense ceramics and glasses. It can also synthesize medical polymer materials, thermosetting coatings, adhesives, etc.
How to Synthesize Hydroxyethyl Methacrylate
The synthetic formula for hydroxyethyl methacrylate
Method 1
100 ml of toluene, 62.1 (1 mol) parts of ethylene glycol, and enzyme (“Novozym 435” manufactured by Novo Corporation, 0.04 parts, 0.01 parts of sodium carbonate, and 0.01 parts of hydroquinone) were loaded into a receiver connected to a cooling tube (for the determination of moisture) and a 1-liter glass flask on the backflow side tube. Heat to 40°C. The portion-wise addition of 72.1 parts (1 mole) of acrylic acid was carried out over 10 minutes with slow stirring. After the addition of the total amount was completed, it was stirred under a reduced pressure of 10 mPa at the same temperature. After the reaction, the catalyst and auxiliary agent were separated by filtration to obtain the target acrylate. The time required to carry out the reaction is about 6 hours. The yield and composition of the obtained acrylates were determined by gas chromatography (hereinafter abbreviated as GC). The yield of hydroxyethyl methacrylate (HEMA) was 98.5% by gas chromatography. As shown in Figure 1.
Method 2
Add 31.05g (EG, 0.5mol) of ethylene glycol, 47.35g (0.55mol) of methacrylic acid, 40g(Inside, 22g water in catalyst before use, 18g dry weight) of strong acidic ion exchange resin(Amberlite IR124: gel type, cross-linking degree 12%, non-porous), 0.086g HO-TEMPO, add 0.086g hydroquinone and 200g toluene. Then heat and stir at 100°C, while adding water at a rate of 2 g/h with a pump. Water formed in the reaction was azeotrope with toluene and removed by a Dean-Stark apparatus. After 5 hours, the conversion of hydroxyethyl methacrylate was 87.3%. As shown in Figure 1.
The Main use of Hydroxyethyl Methacrylate
1. Mainly used for modification of resin and paint. Copolymerize with other acrylic monomers to prepare acrylic resins with active hydroxyl groups in their side chains, which can undergo esterification and crosslinking reactions, synthesize insoluble resins and improve adhesion, and can be used as fiber treatment agents, etc. React with melamine-formaldehyde (or urea-formaldehyde) resin, epoxy resin, etc. to make two-component coatings. Added to the paint of high-end cars, it can maintain the mirror luster for a long time. It can also be used as an adhesive for synthetic textiles and as a medical polymer monomer.
2. Used in the production of resins for coatings, automotive topcoats, and primers. It can also be applied to photopolymerization resins, printing plates, inks, gels (contact lenses), and coatings for canned materials. Embedding reagents for Transmission Electron Microscopy (TEM) and Light Microscopy (LM), especially for hydrated samples of “sensitive antigenic sites”. White watery, viscous, thinner than water, and more permeable than any resin and monomer. Especially useful for working with bone, cartilage, and difficult-to-penetrate plant tissue.
3. In the plastics industry, it is used to manufacture acrylic resins containing active hydroxyl groups. Coating industry and epoxy resin, diisocyanate, melamine formaldehyde resin, and other configurations are used to prepare two-component coatings. In the oil industry, it is used as an additive for lubricating oil washing. In the electronics industry, it is used as a dehydrating agent for electron microscopes. Adhesives are used in the textile industry to make fabrics. Used as a chemical reagent in analytical chemistry. In addition, it is also used as a water-miscible embedding agent for the synthesis of medical polymer materials, thermosetting coatings, and adhesives.
In the End
The above is the main content about the synthetic method of hydroxyethyl methacrylate and its application. Hydroxyethyl methacrylate has a wide range of applications, and its manufacturing method is also very simple. If you need to use hydroxyethyl methacrylate, you can make it as described by Jinbangch. If you need a large amount of Hydroxyethyl Methacrylate, you can always contact Jinbangch for consultation.