MOISTURE-CURE POLYURETHANES – LATEST DEVELOPMENTS IN VOC FREE CONFORMAL COATINGS
Author: Jade P. Bridges Company: Electrolube Ltd. Date Published: 10/24/2010
Abstract: VOCs contribute towards the formation of ground-level ozone, a major component of smog. Such pollution can have many detrimental effects on the environment, in particular, damaging forests and vegetation. VOCs when not managed properly can also cause health problems. Due to the rising concerns surrounding the emissions of VOCs, alternatives to traditional solvent based coatings are at the forefront of product developments. Moisture-cure polyurethanes have been around for many years but have recently been developed to allow for low-viscosity coatings to be produced with the option of accelerated cure using heat and humidity. These coatings have a long pot-life at room temperature and have been tested by the worlds’ leading manufacturers of select spray equipment with extremely positive results; a demand no other solvent replacement technology has achieved so effectively. The cured coatings offer excellent mechanical and electrical properties and can incorporate the use of flame retardants to meet UL94 V0 approval. Due to the excellent properties achieved by these materials, there is scope to push the testing boundaries to investigate the limits of such coatings in comparison with standard materials and potentially identify new applications. Due to the high cross-linked density when cured, these coatings exhibit excellent chemical and humidity resistance and tests are also ongoing to identify their suitability for inhibiting tin whisker growth. The development of these Non-VOC Coatings marks a new era in conformal coatings, paving the way to a greener future.
Key words: VOC, Humidity, Coating, Thermal Cycling, Salt Spray