Non-isocyanate polyurethane wins Green Chemistry Challenge Award
A green polyurethane, which eliminates the use of isocyanates, has won the 2015 Presidential Green Chemistry Challenge Award given by the U.S. Environmental Protection Agency (EPA).
Isocyanates are critical components used in conventional polyurethane products such as coatings and foam.
Causing skin and respiratory problems
However, exposure to isocyanates is known to cause skin and respiratory problems and prolonged exposure has been known to cause severe asthma and even death. Isocyanates are also toxic to wildlife. When burnt, isocyanates form toxic and corrosive fumes including nitrogen oxides and hydrogen cyanide. Due to these hazards, isocyanates are regulated by the EPA and other government agencies.
Crosslinked polymer is the rsult
To address the health and environmental hazards associated with conventional polyurethanes, Hybrid Coating Technologies (HCT) has developed a hybrid non-isocyanate polyurethane (HNIPU), also called “Green Polyurethane.” HNIPU is formed from a reaction between mixture of mono/polycyclic carbonate and epoxy oligomers and aliphatic or cycloaliphatic polyamines with primary amino groups. The result is a crosslinked polymer with β-hydroxyurethane groups of different structure.
HUMs based on vegetable oils
HCT developed a novel concept for generating new multifunctional modifiers for “cold” cure epoxy-amine compositions, namely hydroxyalkyl urethane modifiers (HUM), and subsequently developed HUMs based on renewable raw materials (vegetable oils), which are now used for SPF and UV-cured acrylic polymer based coatings. Utilising HUM provides the cured composition with superior coating performance characteristics including pot life/drying times, strength-stress properties, bonding to a variety of substrates and appearance. Other characteristics, such as weathering and chemical resistance, are also strengthened while HNIPU is not sensitive to moisture in the surrounding environment. HCT also developed a version of its epoxyamine hydroxyurethane grafted polymer that replaces corrosive low-molecular weight amines with less hazardous high-molecular weight amines.
Safer chemical formulation
HNIPU is a safer chemical formulation for use in polyurethane and epoxy applications such as coatings and foam. It also has improved mechanical and chemical resistance properties, replaces up to 50% of its epoxy base with renewable resources (vegetable derived) and is cost competitive compared to other conventional polyurethane and epoxy products.
Cost savings between 30-60%
HCT is currently manufacturing coatings in California with a production capacity of 100,000 tons. Applicators using HNIPU coatings report cost savings between 30-60% due to the product’s improved safety profile and excellent properties. HCT expects to see similar benefits for applicators using its spray polyurethane foam once it becomes commercially available in the next 1-2 years.
