Aluminum Hydroxide Manufacturers: Applications of Aluminum Hydroxide in the Modified Thermoplastic Plastics Industry

When aluminum hydroxide is added to thermoplastic plastics, mechanical strength—particularly impact strength—will decrease. Although coupling agents are used to enhance strength, no significant improvement is achieved.

When aluminum hydroxide is added to thermoplastic plastics, mechanical strength—particularly impact strength—will decrease. Although coupling agents are used to enhance strength, no significant improvement is achieved. Consequently, over 95% of aluminum hydroxide is utilized in thermosetting plastics. Aluminum hydroxide manufacturers provide detailed insights into its applications within the modified thermoplastic plastics industry:

1. Applications in Unsaturated Polyesters

In glass fiber-reinforced unsaturated polyester casting plastics (e.g., various high- or low-voltage electrical switches), aluminum hydroxide serves as a filler to impart flame retardancy, smoke suppression, and arc resistance to plastic products. Aluminum hydroxide from manufacturers is also used in glass fiber-reinforced plastic laminates—such as fiberglass-reinforced bricks, pipes, and storage tanks—delivering excellent flame-retardant performance.

2. Application in Epoxy Resins

In epoxy resins, aluminum hydroxide exhibits unique flame-retardant properties. At a dosage of 40%–60%, it doubles the oxygen index compared to unfilled epoxy resins while simultaneously enhancing arc resistance and electrical endurance. Epoxy resins filled with aluminum hydroxide hold promising prospects in the production of transformers, insulating equipment, switchgear, and similar applications.

3. Applications of Crosslinked Polyethylene and EPDM Rubber in Cables

Among these polymers, crosslinked polyethylene and ethylene propylene diene monomer (EPDM) rubber have been widely adopted due to their excellent electrical insulation properties and enhanced flame retardancy achieved through alumina filling.

4. Applications in Latex and Adhesives

Carpet backing latex rubber and carboxylated latex adhesives represent the earliest market for aluminum hydroxide produced by manufacturers, where consumption remains dominant. It has also replaced calcium carbonate and clay—materials with negligible flame retardancy—as a flame-retardant filler in pre-coatings, adhesives, and foam materials. Typically, 20 to 150 parts of aluminum hydroxide with a particle size of 3 to 20 μm are added to 100 parts of latex, and 75 to 250 parts are added to adhesives. It is estimated that latex precipitation will remain the largest consumer of aluminum hydroxide in the future.

5. Applications in PVC

The most extensively studied field for aluminum hydroxide in thermoplastics is polyvinyl chloride (PVC). It can replace calcium carbonate fillers and is easily incorporated into plasticized PVC. Two methods achieve high flame-retardant standards: one combines aluminum hydroxide with carboxylic acid phosphate plasticizers, while the other combines it with zinc borate. These formulations have been applied to PVC wire and cable materials. In rigid PVC, aluminum hydroxide addition primarily serves to suppress smoke generation.

6. Applications in Polyethylene, Polystyrene, ABS, and Other Thermoplastics

Aluminum hydroxide has been used for flame retardancy in calcium-based plastic panels with satisfactory results. However, in these thermoplastics, aluminum hydroxide must be added at concentrations exceeding 60% to demonstrate significant flame retardancy when used alone, which severely compromises the plastic's impact strength. To date, the application of aluminum hydroxide in these thermoplastics remains an ongoing research focus for aluminum hydroxide manufacturers.