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In use are duroplastic resins which contain sufficient catalysts, UV stabilisers and pigments. Through this mixture, a connection is made to ensure the required mechanical and chemical properties.


The unsaturated polyester resins are among the most commonly used resins in composite materials. UP resins are a colourless to slightly yellow solution of unsaturated polyester in a reactive solvent, usually styrene. At room temperature or by supply of heat, they are cured, whereby a heat reaction is released.

Unsaturated polyester is resistant to:Properties:
• aromatic hydrocarbons• optical: opaque
• aliphatic hydrocarbons
• oil• viscosity: low
• acids
• saline solutions• service temperature:
-30 to 200°C
• petrol
• alcohols


Vinylester resins are produced by reacting epoxides with methacrylic acid. By using vinylester resins as a matrix for GRP Profiles and GRP Gratings a much higher chemical resistance is achieved.

Vinylester resins are resistant to: Properties:
• aromatic hydrocarbons • optical: yellow
• aliphatic hydrocarbons
• acids • viscosity: low
• lyes
• alcohols • service temperature:
-30 to 180°C
• grease
• oil
• petrol

Phenolic resins

Phenolic resins are produced by polycondensation of phenol (m-cresol) with methanal (formaldehyde).

Epoxy resin

Epoxy resins are compounds, which have one or more reactive epoxy and hydroxyl groups. In general, they are formed from bispherol A and epichlorohydrin by polyaddition and polycondensation, combined with subsequent curing.

Epoxy resins are resistant to: Properties:
• aromatic hydrocarbons • optical: opaque
• aliphatic hydrocarbons
• organic solvents
• petrol • viscosity: low
• oil
• alcohols
• saline solutions
• service temperature:
  -30 to 180°C

• acids
• lyes

Acrylic resin

Acrylic resins are synthetic resins, which are produced by polymerisation of acrylic acid, methyl acid and the corresponding esters.

Acrylic resins play a minor role in the pultrusion process. They are usually employed, just like phenolic resins, in areas where high fire resistance and minimal smoke are required.

Acrylic resins are not resistant to: Properties:
• solvents • good burnig properties
• alcohols • low smoke emission
• weather proof
• optical: opaque