1. Raw Material Preparation
(1) Main Raw Materials
- Acrylic acid: It is the main component of acrylic resin and serves as the basic monomer for the polymerization reaction.
- Comonomer: Common comonomers include methyl methacrylate, styrene, acrylate, etc., which are used to control the properties of acrylic resin, such as hardness, adhesion, chemical resistance, etc.
- Crosslinking agent: Such as divinylbenzene or peroxide, used to increase the crosslinking defree of acrylic resin and improve ite heat resistance, mechanical properties, etc.
- Initiator: Such as sodium persulfate, hydrogen peroxide, etc., used to start the polymerization reaction.
(2) Auxiliary Raw Materials
- Solvent: Such as water, alcohol colvents, etc., sometimes used to adjust the viscosity of the reaction system and control the polymerization rate.
- Surfactant: Used in emulsion polymerization to help stabilize the emulsion.
2. Polymerization Reaction
The polymerization of acrylic resin is usually divided into three methods: solution polymerization, emulsion polymerization and suspension polymerization. The operating conditions and raw material ratios of each method are different, but the basic polymerization reaction steps are roughly the same.
3. Post-polymerization Treatment
(1) Termination Reaction
After the polymerization reaction is completed, a terminator needs to be added to stop the polymerization reaction to prevent over-polymerization and ensure that the molecular weight of acrylic resin is within the designed range.
(2) Molecular Weight Regulation
The molecular weight of acrylic resin can be adjusted by adding a chain transfer agent, thereby affecting the fluidity and bonding properties of acrylic resin.
4. Acrylic Resin Preparation and Post-processing
(1) Adjusting Resin Properties
- Plasticizer addition: Add plasticizer to acrylic resin to improve its flexibility adn operability.
- Crosslinker addition: Adding crosslinkers can enhance the heat resistance and mechanical properties of acrylic resin.
- Solvent adjustment: According to the needs of use, appropriate solvents can be added to adjust the viscosity of acrylic resin to make it suitable for different coatings, adhesives and other applications.
(2) Cooling and Separation
After the polymerization is completed, acrylic resin is solidified or a stable emulsion system is formed by cooling. If necessary, impurities can be removed by filtration.
(3) Stabilization and Adjustment
In order to ensure the storage stability of acrylic resin, stabilizers or antioxidants may be added to extend the shelf life of the resin.
5. Finished Product Processing
(1) Drying and Solvent Removal
If a solvent or aqueous solution is used for polymerization, the final acrylic resin needs to be dried to remove excess solvent so that the resin reaches the desired dry solid state.
(2) Final Quality Inspection
After completion, the quality of acrylic resin needs to be inspected to ensure that its molecular weight, viscosity, solid content, acid value, color, etc. meet the specified standards.
(3) Packaging and Storage
Acrylic resin products are packaged according to different application fields. Common packaging forms include barrels, bags, cans, etc. When storing, care should be taken to avoid high temperatures and direct sunlight.