Colloidal stability and rheology of jatropha oil-based waterborne polyurethane (JPU) dispersion

Abstract

Jatropha oil-based waterborne polyurethane (JPU) dispersions were produced by polymerising the jatropha oil-based polyols (JOLs) with isophrene diisocyanate (IPDI) and dimethylol propionic acid (DMPA). The colloidal stability of the resulting JPU dispersions were studied by particle size analysis and rheology measurements. Inclusion of up to 5.4 wt.% of DMPA as an internal emulsifier produced a wide range of particle sizes from 84 nm to 825 nm. The dispersions have a solid content of 24.2-26.9 wt.% with a relatively low viscosity in the range 6.2-60.2 mPa s. The JPU dispersions exhibited the typical flow behaviour of the commercial polyurethane dispersions, ranging from almost Newtonian to a shear thinning fluid, and the experimental data correlated well with the Cross model. The samples were stable after 18 months of storage under room conditions.

Chemical and Thermo-Mechanical Properties of Waterborne Polyurethane Dispersion Derived from Jatropha Oil

“…Jatropha oil-based waterborne PU (JPU) dispersions were synthesised by the acetone process according to the method described in our previous works [ 20 , 25 ]. The schematic for the synthesis of jatropha oil-based waterborne polyurethane (JPU) dispersions is shown in Figure 1 .…”

“…In our previous works, WBPU synthesized from jatropha oil-based polyols were reported, which focused on the wet characteristics such as particle size, zeta potential and rheology. The results show excellent colloidal stability of the dispersion and the rheology is comparable to petrochemical-based WBPU [ 20 ]. The colloidal stability and rheology of the dispersion are important to determining storage stability and applicability of the coatings on substrate [ 21 ].…”

Analysis and Modeling of Viscosity for Aqueous Polyurethane Dispersion as a Function of Shear Rate, Temperature, and Solid Content

“…Previous research 33 − 35 had revealed that multiple kinds of aqueous PUDs tend to exhibit a 2-stage dependence with shear rate: (1) shear thinning in low and intermediate shear rate regions and (2) constant viscosity at high shear rates. 36 As expected, aqueous PUD in this study exhibits characteristics of shear thinning, as shown in Figure 2 .…”

A utilização de óleos vegetais como fonte de polióis para a síntese de poliuretano: uma revisão

“…As características que o poliuretano de óleo de jatrofa possui são boas repelência à água e estabilidade térmica, além de apresentar uma promissora aplicação para revestimentos decorativos. As dispersões desse polímero mostraram um fluxo semelhante de dispersão aos encontrados em poliuretano comerciais segundo Saalah et al (2018).…”