This article provides a brief introduction to acrylic resin and conducts an in-depth research and analysis on the performance and application of acrylate coatings. Based on this study, some suggestions and views are presented, hoping to gain a detailed understanding and grasp of the performance of acrylate coatings, improve the effectiveness of their application, and fully leverage their value and role.
Coatings have a wide range of applications in automobiles, furniture, construction, and other fields. They not only enhance aesthetics but also provide a certain level of protection and extend service life. In the process of socio-economic development, the role of coatings has become increasingly important, and people have a high degree of concern for the performance and quality of coatings. Currently, as people's living standards rise and environmental awareness gradually increases, they are increasingly cherishing the use of resources and have very strict requirements for the quality of coating products. The global coatings industry is developing towards the "4E" principles of economy, ecology, energy, and efficiency. The main raw materials of acrylate coatings are methacrylate or acrylate, which are mixed with resins to form acrylic resin binders. This article conducts research and analysis on the performance and application of acrylate coatings.
2 Acrylic resin
Acrylic resin is a copolymer composed of methacrylate, acrylate, and vinyl monomers. Compared to other synthetic polymer resin materials, acrylic resin materials have very obvious advantages, such as light resistance, weather resistance, durability, heat resistance, etc. They do not discolor at 230℃ and have good acid and alkali corrosion resistance. They are increasingly widely used in automobiles, home appliances, construction, plastic products, etc. Combined with different resin structures and production processes, acrylic numerical coatings can be divided into several different types. 2.1 Relationship between acrylic resin structure and performance
On the one hand, stability includes UV resistance, acid-base resistance, and chemical corrosion resistance. Due to the presence of α-H, acrylate resins have lower oxidation resistance and UV resistance compared to methacrylate resins. Acrylic resins, with C-C bonds as the main chain, exhibit excellent oxidation resistance, acid-base resistance, and hydrolysis resistance. On the other hand, mechanical properties of acrylic resins include extensibility, hardness, toughness, etc., which are largely influenced by the density of the polymer molecular structure. As the side chains grow, the tensile strength and hardness of acrylic resins decrease significantly, while the extensibility and softness increase notably. Polymethacrylates have a methyl group at the α-position, which significantly restricts the rotational movement of the C-C main chain. In polyacrylates, there is no α-methyl group, and each chain can rotate around the main chain, which explains why polymethacrylates have better hardness and tensile strength, but poorer softness and extensibility compared to polyacrylates.
2.2 Synthesis of acrylic resin
Acrylic resin, with radical reaction as its basic reaction, can be divided into three processes: chain initiation, chain propagation, and chain termination, accompanied by chain transfer throughout the entire process. In the synthesis of thermoplastic acrylic resin, it is essential to control the molecular weight and molecular weight distribution. Although the mechanical properties of the paint film will significantly improve with the increase of molecular weight, the solution viscosity of the paint film will also increase significantly, reducing the solid content. In addition, as the molecular weight increases, its solubility tends to decrease. Currently, the molecular weight of thermoplastic acrylic resin used commercially is around 80,000 to 90,000.
The molecular weight and its distribution are also easily influenced by factors such as the monomer feeding method and the type of initiator. When benzoyl peroxide is chosen as the initiator, the benzoyl radical decomposes into a highly reactive radical, which is prone to undergo branching reactions, stripping hydrogen atoms from monomer or polymer molecular chains. Especially with increasing temperature, above 130℃, a large number of branches will appear, widening the molecular weight distribution. In terms of monomer feeding method, choosing the batch feeding method results in a broader molecular weight distribution, while the semi-continuous dropwise addition method and continuous feeding method
The dropwise addition method can obtain a narrower molecular weight distribution. Generally, the solvent is first added to the reaction kettle, heated to the reaction temperature, and then the mixed solution is continuously added at a certain rate to maintain the normal concentration of monomers and initiators in the reaction kettle. If the rate of monomer addition can maintain the normal polymerization temperature, the monomer concentration in the reaction kettle is basically constant. In the reaction of vinyl monomer copolymers, it is also necessary to fully analyze and consider the monomer reactivity ratio. If the reaction rate constants of each monomer are similar, the molecular chain structure can be regarded as randomly distributed. If there are significant differences in the reaction rate constants of each monomer, choosing the batch feeding method will easily affect the uniformity of the molecular chain composition. Choosing the semi-continuous dropwise addition method and continuous dropwise addition method, controlling the monomer dropwise addition rate, and keeping it consistent with the polymerization rate can obtain an average composition molecular chain.
3 Main properties and applications of acrylate coatings
Acrylate coating raw materials are derived from petrochemical production, with low cost and abundant resource reserves. In the development process of acrylate coatings, in order to improve performance and reduce production costs, olefin monomers such as acrylamide and styrene are also used. The characteristics of different copolymers vary, and it is necessary to combine specific product requirements to clarify different types of coatings.
3.1 Main properties of acrylate coatings
The performance of acrylate coatings is concentrated in the following aspects: Firstly, they have excellent gloss and can be made into water-white varnish or pure white enamel paint; secondly, they have excellent lightfastness and will not yellow or decompose under ultraviolet radiation, maintaining their original color for a long time; thirdly, they have good heat resistance and can be used as neutral coatings, mixed with aluminum powder and copper powder to achieve a gold or silver-like color, resistant to acid and alkali corrosion, and resistant to grease; fourthly, they can be stored for a long time without deterioration.
3.2 Main applications of acrylate coatings
Due to its excellent performance, acrylic paint is currently widely used in various fields such as automotive decoration, home appliances, machinery, instruments, construction, and leather, making it a new type of high-quality paint. It can be divided into three different types: solvent-based acrylic paint, water-based acrylic paint, and solvent-free acrylic paint.
Solvent-based acrylate coatings are categorized into thermoplastic and thermosetting types. Thermoplastic acrylate coatings are more suitable for applications in industries such as building exterior wall spraying and automotive refinishing paints. To effectively control environmental pollution issues, non-photoactive solvents can be used. Thermosetting acrylate coatings include hydroxy acrylate coatings, epoxy acrylate coatings, etc. When choosing a curing agent, amino resin can be applied to household appliances, automotive topcoats, etc. Polyisocyanate can be selected as a curing agent for automotive topcoats, building exterior wall coatings, etc. Polyamine or polyacid can be chosen as a curing agent for can spraying, etc. Epoxy resin can be selected as a curing agent for can spraying, etc. Melamine resin can be chosen as a curing agent for base and mid-coat coatings, and it also has excellent application effects in furniture metal coatings.
Waterborne acrylate coatings are divided into two types: thermoplastic acrylate lotion paints and thermosetting acrylate lotion paints. Thermoplastic acrylate lotion paints are mainly used in exterior wall coatings, waterborne road marking paints, and metal anti-corrosion coatings. Thermosetting acrylate lotion paints include emulsion type, water-dilutable type, and aqueous solution type. The emulsion type is applied in road marking paints, exterior and interior wall coatings, etc. The water-dilutable type is mainly used in automotive electrophoretic primers, aluminum door and window frames, etc. The aqueous solution type is mainly used in automotive primers, household parts coating, etc.
Solvent-free acrylate coatings primarily encompass two types: thermosetting UV-curable coatings and thermosetting acrylate powder coatings. UV-curable coatings find applications in optical fiber coatings, wood coatings, plastic coatings, and other fields. Acrylate powder coatings are utilized in coatings for guardrails, aluminum wheel hubs, and have recently begun to be applied in automotive topcoats and other domains.
3.3 Water-based acrylate coatings
The technology of water-based paint started relatively late, but its process has gradually matured, featuring environmental protection and energy conservation. It has gradually developed into a major direction of modern paint development, with its varieties, functions, and applications becoming increasingly perfect. Among the currently developed water-based paints, in terms of curing temperature, latex paint can achieve curing at 2°C abroad. In terms of application scope, architectural paint is the most widely used, and water-based polyurethane paint has been successfully developed. The successful research and development of acrylate lotion has laid a good foundation for the realization of water-based paint. In practical applications, acrylate lotion has good performance characteristics, such as non-pollution, and can also be formulated into coatings with excellent construction performance, ensuring effective safety during use. Water-based acrylate has a relatively simple composition and currently struggles to meet the practical needs of high-performance audio-visual fields. Modifying acrylic resin with epoxy resin can obtain water-based anti-corrosion and anti-rust coatings with good performance, while modifying acrylic phenol with silicone can obtain high-performance water-based architectural paint.
Conclusion
Acrylic coatings exhibit excellent performance in practical applications and are widely used in various fields such as automotive decoration, home appliances, machinery, instruments, construction, and leather. They constitute a new type of high-quality coatings, encompassing different types such as solvent-based acrylic coatings, water-based acrylic coatings, and solvent-free acrylic coatings. In practical use, acrylic coatings can be customized according to specific needs by adding different curing agents to achieve various properties, thereby better meeting the requirements of use.
Post time: Jul-20-2026