Biobased, Nonisocyanate, 2K Polyurethane Coatings Produced from Polycarbamate and Dialdehyde Cross-linking

Abstract

Bioderived polycarbamates were cross-linked with petrochemically derived and biomass-derived dialdehydes to form nonisocyanate polyurethanes (NIPUs). The bioderived polycarbamates were synthesized from a soybean oilderived alkyd polyol and epoxidized sucrose soyate polyol via transcarbamoylation. The polycarbamates were cross-linked with 1,4-cyclohexanedicarboxaldehyde and 2,5diformylfuran (DFF) to form coatings under either laboratory ambient conditions or through an elevated temperature cure. The coatings were characterized spectroscopically, thermally, and via standard ASTM-coating characterizations. The coatings cured under ambient conditions had similar properties to those subjected to the elevated temperature cure. Ambient-cured coatings exhibited fast tack-free times, T g values from 67 to 96 °C, high hardness, and good solvent resistance; however, they were brittle and had poor adhesion on aluminum substrates. Coatings cured at elevated temperatures showed increases in T g values to 75−150 °C. Coatings on pretreated steel substrates had good adhesion. This study demonstrates the potential for bioderived DFF to function as a dialdehyde cross-linker to form NIPUs with bioderived carbamate functional resins resulting in a bioderived NIPU capable of ambient curing. Given the potential to form a multitude of aldehyde-functionalized furanic structures from 5-(hydroxymethyl)furfural, this increases the dialdehyde cross-linker options under consideration for formulation in bioderived NIPUs utilizing aldehyde-carbamate cross-linking.

Selective Catalytic Synthesis of 1,2‐ and 8,9‐Cyclic Limonene Carbonates as Versatile Building Blocks for Novel Hydroxyurethanes

“…The successful synthesis of hydroxyurethanes 8 and 9 demonstrates the potentialo fm onofunctionalised terpene-derived cyclic carbonatesf or renewable polymer synthesis:w hereas the reaction of 6 and 7 with diamines would furnish linear polyurethanes, the reactiono f3 and 5 with polyfunctional amines would give access to pre-polymers that may be further functionalised on the remaining double bond. [57][58][59]…”

Hybrid alkyds, the glowing route to reach cutting-edge properties?

“…JCO based NIPU was obtained by reacting CC-AR with diamines such as isophorone diamine (IPDA) (Scheme 19). Films obtained with JCO based NIPU exhibited good chemical resistance to water, acid and alkali solutions.Additionally, the cross-linking of polycarbamates with dialdehydes has been reported in a US patent as a fast ambient cure NIPU route 149,150. Silbert et al have investigated this novel route to synthetize NIPU with biobased reactants and obtained coatings with a thickness around 30 µm, which exhibited strong hardness and good solvent resistance.…”

Highly Selective Photocatalytic Oxidation Biomass Valorization Over Nb2O5/g‐C3N4Heterojunction

“…[2][3][4][5] Among these derivatives, 2,5diformylfurane (DFF) is utilized as a crucial raw material for syntheses of a variety of chemical products, involving fluorescent material, biocides, coatings, plasticizers, and pharmaceutical intermediates. [6][7][8][9][10] Therefore, the selective transformation to DFF is of high value and great significance in the oxidation conversion of HMF.…”