Sika Technology AG and Incorez Ltd. | Date: 2011-06-01
The present invention relates to non-crystallising oxazolidines as curing agents for polyisocyanates, respectively polyurethanes. These curing agents are essentially mixtures of at least one polyoxazolidine POU having at least two urethane groups and at least one polyoxazolidine POC having at least one carbonato group.
Carter N.,Incorez Ltd |
Evans C.,Incorez Ltd |
Easthope S.,Incorez Ltd
Polymers Paint Colour Journal | Year: 2011
Polyurethane (PU) formulators need to address several challenges when developing new technologies. The challenges include retaining and improving performance cure and physical properties of PU systems, meeting legislation demands such as volatile organic compound (VOC) reduction and reducing toxicity by decreasing isocyanate concentration. Oxazolidine technology, available in the Incozol range of products supplied by Incorez, offers a low toxicity solution to formulators of both one and two-component polyurethane systems to address moisture related formulation issues. Oxazolidines are widely used in one-component aliphatic and aromatic polyurethane cartridge sealants. These high performance elastomeric polyurethane sealants require no mixing and typically no priming to adhere to many substrates, including concrete. A non-crystallising grade of urethane bis-oxazolidine that remains liquid at temperatures down to -10°C reduces the energy and handling costs associated with melting product.
Trivedi T.,Incorez Ltd.
European Coatings Journal | Year: 2013
A new water-soluble epoxy hardener for epoxy- based floor coatings has been developed by using a controlled molecular architecture. The hardener is VOC-free with very low free amine monomer levels. Many waterborne epoxy systems are relatively low in viscosity and thus are easy to apply and can level into a smooth film or layer after application. Water-based curing agents can eliminate or reduce volatile organic compounds (VOC) in the formulations, and so reduce the odor and environmental and health risks associated with the presence of such compounds. Shrinkage is caused by high tension in a cured network which has a high level of internal energy. The architectural design of the hardener is critical to controlling the level of shrinkage. Poor distribution of crosslinking or branching sites can lead to high localized tension in the polymer network. This is increasingly a problem in high build systems such as self-leveling formulations where the binder content is normally low.