Poly(hydroxyurethane) Adhesives and Coatings: State-of-the-Art and Future Directions

Abstract

Polyurethane (PU) adhesives and coatings are widely used to fabricate high-quality materials due to their excellent properties and their versatile nature, which stems from the wide range of commercially available polyisocyanate and polyol precursors. This polymer family has traditionally been used in a wide range of adhesive applications including the bonding of footwear soles, bonding of wood (flooring) to concrete (subflooring), in the automotive industry for adhering different car parts, and in rotor blades, in which large surfaces are required to be adhered. Moreover, PUs are also frequently applied as coatings/paints for automotive finishes and can be applied over a wide range of substrates such as wood, metal, plastic, and textiles. One of the major drawbacks of this polymer family lies in the use of toxic isocyanate-based starting materials. In the context of the REACH regulation, which places restrictions on the use of substances containing free isocyanates, it is now urgent to find greener routes to PUs. While non-isocyanate polyurethanes (NIPUs) based on the polyaddition of poly(cyclic carbonate)s to polyamines have emerged in the past decade as greener alternatives to conventional PUs, their industrial implementation is at an early stage of development. In this review article, recent advances in the application of NIPUs in the field of adhesives and coatings are summarized. The article also draws attention to the opportunities and challenges of implementing NIPUs at the industrial scale.

Fully Biobased Vitrimers: Future Direction toward Sustainable Cross‐Linked Polymers

“…Today, poly(hydroxyurethane)s (PHU)s, synthesized by polyaddition of cyclic carbonates and amines, are considered as greener alternatives to conventional polyurethanes ( Figure ). [ 119–122 ] PHUs bear additional primary or secondary hydroxyl groups, in comparison to classic polyurethanes, that faster bond exchanges and enable the preparation of vitrimers. [ 123 ]…”

Novel Biobased Epoxy Thermosets and Coatings from Poly(limonene carbonate) Oxide and Synthetic Hardeners

“… 2 , 5 Examples of biobased precursors include glycols, natural oils, and fatty acids used in resin production 6 , 7 and agricultural byproducts such as starch and lignin compounds. 3 , 8 − 10 However, in the quest to find and identify renewable raw materials for use in coatings and adhesives, epoxy materials are lagging behind compared to other polymers (e.g., biobased polyurethanes and polyesters) 5 , 11 to be released as commercially available products. For instance, one-to-one replacement of petroleum-based products with epoxy biobased products is not yet possible.…”

A Biosourced Epoxy Resin for Adhesive Thermoset Applications

“…Notwithstanding, some promising results towards new adhesive and coating technologies have emerged. Gomez-Lopez et al [16] recently reported an overview on poly(hydroxyurethane) polymers derived from biobased poly(cyclic carbonate)s and synthetic diamines. The polycarbonate precursor can react with both aliphatic and cyclic amines, and with highly reactive melamines, such as hexamethoxy methyl melamine (HMMM), to produce solvent-based and solvent-free thermosets.…”

“…Notwithstanding, some promising results towards new adhesive and coating technologies have emerged. Gomez‐Lopez et al [16] . recently reported an overview on poly(hydroxyurethane) polymers derived from biobased poly(cyclic carbonate)s and synthetic diamines.…”