Aromatic resin refers to a resinous substance produced by a series of polymerization reactions between substances containing certain functional groups (such as carbon-carbon double bonds, ester groups, carbonyl groups, hydroxyl groups, etc.) and aromatic compounds. The aromatic resin has a ring structure and a large molecular weight. In general, aromatic resins have excellent high temperature resistance, good corrosion resistance and low viscosity.
Because aromatic resins have the advantages of rich variety and good physical and chemical properties, they are widely used in coatings, electronic appliances, aerospace, 3D printing and environmental protection.
- Coatings: Aromatic resins have a very wide range of applications in the field of coatings. Aromatic resins are generally not used directly as coatings, but are usually added as additives to certain types of coatings, thereby improving the physical and chemical properties of the coatings and making the coatings of greater application value. For example, perchloroethylene coatings are affected by the structure, the product has poor adhesion, low solubility, and the produced film is thin, so its application is limited. Xylene formaldehyde resin is a type of aromatic resin. The molecular structure contains hydroxyl, ether bond and other active groups. It can be dissolved in a variety of polymers, such as polyvinyl chloride, nitrocellulose, perchlorinated vinyl chloride, polyurethane, epoxy resin, unsaturated polyester resin, melamine resin, etc. Adding xylene formaldehyde resin to the perchloroethylene coating can play the role of plasticizing, toughening, increasing bonding strength and improving gloss, thereby greatly improving the overall performance of the perchloroethylene resin.
Figure 1. Xylene formaldehyde resin molecular structure
- Electronic appliances: Some aromatic resins have good corrosion resistance, excellent dimensional stability, high insulation and strength, and have been widely used in the field of electronic packaging materials. Among them, the most widely used aromatic resin in the field of electronic appliances is epoxy resin. For example, using 1,10-phenanthroline monohydrate, benzoquinone, and anhydrous N,N-dimethylformamide as raw materials, a new epoxy resin containing both a diafluorene structure and a silicon group in the structure can be synthesized. Then, the new epoxy resin is blended with the bisphenol A type epoxy resin, and the obtained epoxy cured resin has more excellent mechanical strength, flame retardancy and heat resistance than the traditional bisphenol A type epoxy resin. This epoxy curing resin can be used to make microelectronic devices.
Figure 2. New epoxy resin containing diazofluorene structure and silicon group
- Other fields: In addition to the above fields, aromatic resins also have great application value in many other fields. For example, adhesives are often used during 3D printing. Thermosetting phenolic resin has the characteristics of high strength, high temperature resistance and good adhesion, and can be used as an adhesive for 3D printing. In addition, aromatic resins also have certain applications in the field of environmental protection. Dicyandiamide formaldehyde resin is an organic polymer cationic flocculant. Through chemical bonding reaction and electrical neutralization, it can effectively adsorb the pollutants in the wastewater together to form a large flocculent, thereby playing a role in purifying the wastewater.
Figure 3. Thermosetting phenolic resin for 3D printing
According to different polymerized functional groups in the resin structure, aromatic resins can be classified into aromatic polyamide resins, aromatic petroleum resins, aromatic polyurethane resins, aromatic phenolic resins, and the like.
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