Novel Internal Emulsifiers for High Biocontent Sustainable Pressure Sensitive Adhesives

Abstract

In this paper, two novel fully renewable internal emulsifiers have been successfully synthesized from epoxidized soybean oil and natural acids (adipic and pimelic acid) by a solvent-free and self-catalytic method. It is found that the emulsifiers show similar chemical structure and functions with typical petroleum based internal emulsifiers (dimethylol butanoic acid and dimethylol propionic acid), in which the hydroxyl groups act as a cross-linking and the carboxylic acid groups provide the ionic segment. These two novel internal emulsifiers were employed together with castor oil to prepare a series of high biocontent anionic waterborne polyurethane dispersions (PUDs). The unique structure of these two emulsifiers and their good compatibility with castor oil offer PUDs excellent storage stability. Additionally, the biocontent of the polyurethane are high up to 77.7%. Moreover, the adhesive properties of the biobased pressure sensitive adhesives (PSA) were comprehensively investigated by shear resistance, tack, and 180°peel strength test. The PSAs had a shear strength of 1.18 h to more than 100 h, a tack of 1.78−5.66 N, and a peel strength of 1.23−2.77 N/mm, all WPU PSA show good pressure sensitive adhesive properties, which would further expand the application of these novel vegetable oil-based waterborne PUDs.

High Water Resistance and Enhanced Mechanical Properties of Bio-Based Waterborne Polyurethane Enabled by in-situ Construction of Interpenetrating Polymer Network

“…Recently, the application of renewable resources as a replacement of fossil feed stock to develop bio-based chemicals (such as polyols, isocyanates and hydrophilic chain extenders, etc.) and therefrom endow the sustainability and green characteristics of the final products of WPU [4].…”

Composite waterborne polyurethane reinforced with silane modified lignin as an adhesive between polypropylene decorative films and wood‐based panels

“…Thus, the incorporation of thermally stable compatibilizers into WPU forming suitable composites may compensate for this deficiency. [ 22–24 ]…”

“…Thus, the incorporation of thermally stable compatibilizers into WPU forming suitable composites may compensate for this deficiency. [22][23][24] Within the class of wood-based materials, lignin is, after cellulose, the second most abundant renewable biopolymer, where lignin is generated as one of the byproducts from the paper and pulp industry. Thus, it may have great potential for polymer modifications as a kind of low-cost fillers.…”

Enhanced Water Resistance Performance of Castor Oil—Based Waterborne Polyurethane Modified by Methoxysilane Coupling Agents via Thiol-Ene Photo Click Reaction

“…Nowadays, waterborne polyurethanes (WPUs) have become one of the most attractive polymers in the past decade. WPUs using water as solvent is eco-friendly and they can not only mainly retain the properties of PUs in an organic solvent, but also exhibit the distinctive properties of low viscosity at high molecular weights, low VOCs emissions, excellent weather ability [12][13][14]. WPUs have become one of the most rapidly growing and active branches of polyurethane chemistry and technology.…”