Preparation and Properties of Autocatalytic Biobased Waterborne Polyol from Rosin Based Epoxy Resin

Abstract

Due to the complex heterogeneous lm forming process of two-component waterborne polyurethane (2K-WPU), the crosslinking reaction rate of 2K-WPU cannot meet the demand of e cient application in coatings. In order to improve the crosslinking reaction rate of 2K-WPU, a waterborne polyol containing tertiary amine groups was synthesized from rosin based epoxy resin and secondary amine compound, and then autocatalytic 2K-WPU was prepared by crosslinking the rosin based waterborne amino polyol with polyisocyanate. The structure of the polyol from rosin based epoxy resin was characterized with Fourier infrared (FT-IR) and nuclear magnetic resonance (NMR). The crosslinking kinetics and the crosslinked product of the rosin based waterborne amino polyol were also compared with a commercial acrylic polyol. It was shown from the results that the crosslinking reaction rate of the rosin based waterborne amino polyol was faster than that of the commercial acrylic polyol, which indicated the tertiary amine groups chemically bonded in the rosin based polyols could autocatalyze the crosslinking reaction of 2K-WPUs with catalysts free. The lm of the rosin based waterborne amino polyol had excellent impact strength, adhesion, exibility, hardness, gloss, fullness and solvent resistance, showing a good application prospect in the eld of waterborne coatings.

One‐Step Solvent‐Free Synthesis of Dimer Diamine‐Based Autocatalytic Polyol for the Preparation of Polyurethane Foams

“…[18][19][20] There are commercial ACPs that are mainly synthesized from the ethoxylation or propoxylation of amines such as ethylene diamine, triethanolamine, and aniline [21] To our best knowledge, there are only a couple of bio-based commercial ACPs [22] and a limited number of publications. [23][24][25][26][27][28] One of the first examples of bio-based ACPs can be found in a patent document that describes the synthesis of ACPs via the ring-opening reaction of epoxidized vegetable oils by various amines such as ethylenediamine, and diethanolamine. [23] In an periodical patent document, the reaction of epoxidized soybean oil with diethanolamine at >100 °C was disclosed.…”

“…[27] Recently, Wu et al performed autocatalytic polyol synthesis with rosin obtained from pine trees. [28] First, a trifunctional epoxy resin was obtained by reacting maleic anhydride-modified rosin with ECH. By reacting this resin with benzylethanolamine, they prepared an autocatalytic polyol which was used to obtain a water-based polyurethane dispersion.…”

“…In addition, some of the previously utilized reactions have low atom economy or generate byproducts. [24,27,28] For instance, the APC prepared from the reaction of epoxidized soybean oil with diethanolamine generates glycerol and the synthesis of the rosinbased trifunctional epoxy resin by using ECH formed NaCl as byproducts. [28] The generation of these high molecular weight byproducts (i.e., glycerol or NaCl) leads to low atom economy.…”

“…[24,27,28] For instance, the APC prepared from the reaction of epoxidized soybean oil with diethanolamine generates glycerol and the synthesis of the rosinbased trifunctional epoxy resin by using ECH formed NaCl as byproducts. [28] The generation of these high molecular weight byproducts (i.e., glycerol or NaCl) leads to low atom economy. Therefore, more environmentally friendly alternatives are needed.…”

Biobased Polyurethane Adhesives Derived from Vegetable Oil and Rosin for Flexible Packaging Applications

“…9 Rosin, a naturally available and renewable material, exhibits high thermal stability and hydrophobicity due to its tricyclic phenanthrene structure, containing cyclic esters and aromatic hydrocarbons. 10 PUs incorporated with rosin and its derivatives have been used in a wide range of applications like coatings, 11 PU foams, 12 and adhesives. For example, the effects of the rosin content on the properties of pressure-sensitive adhesives (PSAs) made from PU/polysiloxane copolymers were investigated.…”