Polyester – Chemicals used in the composite sector

Chemicals Used in the Polyester-Composite Industry and Their Applications

The polyester-composite industry produces durable, lightweight, and long-lasting structures by combining resins with reinforcement materials such as fiberglass and carbon fiber. The chemicals used in this process directly affect the mechanical strength, chemical resistance, and processability of the product. The products we supply are listed below:

Our main products:

• Acetone
• Polyester Cleaner
• Polyester

Below, the main chemicals used in the polyester-composite industry and their usage methods are explained in detail:

1.Unsaturated Polyester Resins (UPR – Unsaturated Polyester Resins)

It is the basic binder of composites.

• Orthophthalic resin:General purpose use

• Isophthalic resin:Higher chemical and thermal resistance

• Vinyl ester resin:Superior durability in acidic and chemical environments

Usage:In production techniques such as hand lay-up, RTM (Resin Transfer Molding), pultrusion, and filament winding

2.Hardeners / Curing Agents

Ensures the resin solidifies through chemical reaction.

• MEKP (Methyl Ethyl Ketone Peroxide):Provides curing at room temperature

• Benzoyl Peroxide (BPO):For more controlled curing at low temperatures

Usage:Added to the resin in the appropriate ratio; the curing time and temperature are adjusted accordingly.

3.Accelerators / Promoters

Accelerates the effect of hardeners, shortens cure time.

• Cobalt naphthenate or octoate:Used with MEKP

• DMA (Dimethylaniline):Effective in BPO systems

Usage:Used to control the reaction rate of the mixture.

4.Fillers

Reduces cost, improves physical properties.

• Calcite (CaCO₃):Most common filler, provides hardness and matte finish

• Talc(Mg₃Si₄O₁₀(OH)₂):Provides surface smoothness

• Aluminum trihydrate (ATH):Provides flame retardant properties

5.Reinforcements

Provides mechanical strength to the composite.

• Fiberglass (E-glass):Common and cost-effective

• Carbon fiber:High strength and lightness

• Aramid (Kevlar):In applications requiring high impact resistance

6.Release Agents and Mold Chemicals

Ensures the composite material is easily removed from the mold.

• PVA (Polyvinyl Alcohol):Forms a film

• Silicone-based sprays:Provides permanent release properties

7.Gelcoat and Topcoat Products

Improves surface quality, provides UV and chemical resistance.

• Iso resin-based gelcoat:Higher outdoor durability

• Pigmented gelcoats:Aesthetic and functional surface appearance

8.Additives

Used for processing ease and product quality.

• Air entraining agents:Reduces bubble formation

• UV stabilizers:Resistance to sunlight

• Flame retardants:Protection against fire risk