PP composite board, a material composed of a polypropylene (PP) substrate and a reinforcing layer, benefits greatly from its surface treatment, which significantly alters its performance. Different surface treatment technologies can significantly improve the adhesion, wettability, abrasion resistance, chemical corrosion resistance, and aesthetic appearance of PP composite board, thus meeting a wider range of application needs.
Plasma treatment is a common method for enhancing the performance of PP composite board. This technology uses a high-energy electron beam to bombard the material surface, roughening it and increasing its surface activity. This treatment introduces numerous polar groups, such as hydroxyl and carboxyl groups, onto the PP composite board surface, significantly increasing its surface energy. The increased surface energy strengthens the bond between the PP composite board and adhesives, coatings, or other materials, thereby improving adhesion. For example, in automotive interior parts, plasma-treated PP composite board exhibits significantly improved bonding strength with glass fiber, effectively preventing delamination.
Flame treatment removes the oxide layer and increases surface roughness by heating the material surface with a flame. This treatment also improves the adhesion of PP composite board, making it particularly suitable for applications with stringent environmental requirements. Flame treatment eliminates the need for chemical reagents, reducing environmental pollution risks. However, strict temperature and time control are crucial to prevent overheating and deformation of the material. Flame-treated PP composite boards exhibit excellent bonding stability in packaging, construction, and other fields.
Corona treatment utilizes corona discharge to induce corona discharge on the material surface, increasing surface activity and roughness. This technology reduces surface tension by altering the polarity of the PP composite board surface, making it easier for paints and adhesives to wet the surface. Corona treatment is simple to operate and suitable for large-scale continuous production, but the treatment effect may be affected by factors such as material thickness and ambient humidity. In the electronics and electrical appliance industry, corona-treated PP composite boards are often used to manufacture housings and structural components, ensuring coating adhesion and durability.
Chemical treatment introduces polar groups, such as carboxyl and sulfonic acid groups, into the PP composite board surface through strong oxidation or corrosion. This treatment significantly improves the adhesion between the material and resin, enhancing the overall strength of the composite structure. For example, chemical treatment of PP composite board with solutions such as potassium chromate and concentrated sulfuric acid significantly increases its surface free energy and improves its adhesion to materials like metals and ceramics. Care must be taken with the concentration, temperature, and treatment time of the solution during chemical treatment to avoid excessive corrosion that could degrade material properties.
Coating treatment involves applying a functional coating, such as paint, silicone, or UV-protective coating, to the surface of the PP composite board, improving its appearance or adding specific functions. Coating treatment not only enhances the wear resistance and chemical corrosion resistance of PP composite board but also imparts properties such as UV resistance and antistatic properties. For example, in outdoor billboards, PP composite board coated with a UV-protective coating effectively resists UV aging and extends its service life. Coating treatment requires selecting appropriate coating materials and processes based on the application scenario to ensure the adhesion and durability of the coating to the substrate.
Sandblasting treatment uses high-speed jets of abrasive particles to impact the material surface, removing the oxide layer and increasing surface roughness. This treatment significantly improves the adhesion performance of PP composite board, making it particularly suitable for applications requiring high surface roughness. Sandblasting creates a micro-textured surface on PP composite board, increasing the contact area with adhesives and thus improving bond strength. In the aerospace field, sandblasted PP composite board is often used to manufacture lightweight structural components, ensuring their stability in extreme environments.
Surface treatments of PP composite board significantly alter its performance. Through techniques such as plasma treatment, flame treatment, corona treatment, chemical treatment, coating treatment, and sandblasting, the adhesive properties, wettability, abrasion resistance, chemical corrosion resistance, and aesthetic appearance of PP composite board can all be significantly improved. The choice of these treatment methods must be carefully weighed based on specific application requirements and environmental conditions to ensure optimal performance of the PP composite board in various fields.
