Synthesis and Properties of Sulfonated Waterborne Polyurethane Modified by ESO-based Polyols

Polyols based epoxidized soybean oil was synthesized by ring-opening addition reaction of epoxidized soybean oil with 2-ethyl hexanol (isooctanol). Then sulfonated waterborne polyurethane was synthesized using isophorone diisocyanate (IPDI), polycaprolactone diol (PCL), ethylenediamine sodium acetate (AAS) and the ESO-based polyols, and the film had been fabricated successfully by using the obtained waterborne polyurethane as the binder. Polyols was characterized by FTIR and H-1-NMR, which indicated polyols was successfully synthesized in the experiment. Influence of the content of polyols on the properties of sulfonated waterborne polyurethane emulsions and their films was evaluated by a series of measurements, including particle size test, water absorption test, static contact angle test, mechanical performance test and TGA. The results showed that the sulfonated waterborne polyurethane modified by ESO-based polyols had been successfully synthesized confirmed by FTIR, and with the increase of the content of polyols, the particle size of the sulfonated waterborne polyurethane emulsion increased gradually, the water absorption of the film decreased and then flatten out when the content of polyols continued to increase during the fabrication of the modified sulfonated waterborne polyurethane. Furthermore, the tensile strength of the film of sulfonated waterborne polyurethane increased, and elongation at break decreased with the increase of the content of polyols. However, too large amount of polyols in the synthesis process of sulfonated waterborne polyurethane would result in destabilization of the emulsion dispersion and lead to failure of the emulsion at last. The film of sulfonated waterborne polyurethane presented the superior performance when the mass ratio of polyols and PCL was 0. 2. Water absorption rate of the film decreased from 50. 14% to 12. 27%, the water contact angle came to 103. 3 degrees, and the tensile strength increased greatly from 8. 16 MPa to 21. 77 MPa as the mass ratio of polyols and PCL increasing from 0 to 0. 2. At last, the TG analysis showed the improvement Of heat resistance of the film, which would be attributed to the incorporation of polyols.