Reduction of Styrene Content in Unsaturated Polyester (UPE) and Vinyl Ester (VE) Resins

• A Material
• A Technology

Identify a safe, cost-effective alternative to styrene that can be used as a reactive diluent in unsaturated polyester (UPE) and vinyl ester (VE) thermosetting resins for composite fabrication. The reactive diluent should replace at least 50% of the styrene while enabling the processability and performance properties of existing UPE and VE resins to be maintained.

Provide composite fabricators who are facing EH&S pressure to reduce styrene emissions from thermosetting UPE and VE resins with products that have the potential to reduce styrene exposure by 50% while maintaining existing processability and performance properties.

Thermoset composites that utilize unsaturated polyester (UPE) and vinyl ester (VE resins) find widespread application in the transportation and building & construction markets. Examples of applications include fiberglass-reinforced UPE resins for truck hoods and boat hulls, reinforced VE resins for corrosion-resistant pipes and tanks, and aggregate-containing UPE resins for solid surface, tub and shower applications.
Styrene is a key component in these formulations. It is a reactive diluent that serves two functions: 1) it serves as a diluent that reduces the viscosity of the UPE or VE resin to a useable viscosity and 2) it is a reactive monomer that participates in the free radical crosslinking reactions that occur during cure of the resin.

In recent years, styrene has come under increasing EH&S scrutiny. Since Risk = [Exposure x Hazard], our intent is to reduce possible worker exposure by providing formulations with significantly lower styrene content, particularly for open mold applications where workers are more prone to exposure to styrene vapors.. We would like to replace at least 50% of the styrene with an alternative reactive diluent.

• A liquid reactive diluent that:
  • Costs no more than 2x styrene (styrene currently sells for about 55 cents per pound)
  • Has a viscosity no more than 5x styrene; styrene's viscosity is 0.76 centipoise at room temp
  • Can dissolve UPE and VE resins like styrene
  • Is no more hazardous than styrene. The alternative to styrene should have higher exposure limits than styrene, must have a higher flash point, and must not be a Hazardous Air Pollutant.
  • Has reactivity comparable to styrene in free-radical curing reactions
• Pilot scale or commercial scale materials strongly preferred; lab-scale acceptable

• Substituted styrenes (other than methyl derivatives mentioned below)
• Short chain oligomers of styrene with multifunctional aromatics (eg., divinylbenzene) or acylates or methacrylates. The oligomer must contain residual unsaturation.
• Derivatives of dicyclopentadiene (DCPD)
• Conjugated dienes

• a-Methyl Styrene (not reactive enough)
• Vinyl Toluene & individual isomers (low reactivity and unpleasant odor)
• Methyl Methacrylate (odor, volatility, reactivity issues)
• Diallyl Phthalate (high viscosity, low reactivity)

We would like to introduce the first products within the next two to three years.

• Cost per pound
• Viscosity, solvent properties
• Cure speed in free radical-cured reactions
• Toxicity, flash point

• Proven Concepts
• Ready To Use Solutions

• Business Type: Specialty Chemicals
• Annual Revenue: Multiple Billions
• Years in Business: >75
• Headquarters Location: USA