Date of Award

Fall 12-12-2025

Document Type

Thesis

Degree Name

Master of Science (MS)

Department

Materials Science

First Advisor

Dr. Ram K. Gupta

Second Advisor

Dr. Serif Uran

Third Advisor

Dr. Timothy Dawsey

Keywords

3-aminoproylethoxy, silane, Ajay, Kumar, CEA-5wt.%

Abstract

The development of sustainable and environmentally friendly polyurethane coatings has garnered significant attention in recent years. This research focuses on the development of isocyanate-free coatings derived from carbonated soybean oil (CSBO) using a solvent- and catalyst-free approach. The coatings were synthesized by reacting CSBO with ethylenediamine (EDA) and varying weight percentages of 3-aminopropyltriethoxysilane (APTES), which were added to enhance the coating property, as it contains silicon in it, to evaluate their mechanical and thermal properties. Fourier Transform Infrared Spectroscopy (FTIR) confirmed the successful formation of urethane linkages, with a significant reduction in C=O peak intensity after 10 days of curing, indicating enhanced crosslinking. Mechanical testing revealed that films containing 5 wt.% APTES exhibited the highest tensile stress of 1.29 MPa due to optimal crosslink density, which balanced rigidity and flexibility. The best elongation at break was observed at 20 wt.% APTES, attributed to increased molecular interactions that allowed better energy dissipation under stress. Thermogravimetric Analysis (TGA) indicated that coatings with 15 wt.% APTES had the highest degradation temperature at 7.01 °C, suggesting a well-structured polymer matrix with improved thermal resistance. Tensile adhesion tests on oak wood substrates showed a maximum bonding strength of 3.6 MPa of 10 wt.% APTES, owing to optimal silane interaction with the substrate, promotes better adhesion. These findings suggest that silicon-modified bio-based polyurethane coatings can serve as sustainable alternatives to traditional isocyanate-based systems while achieving superior mechanical and thermal performance. Also, we performed some other characterizations, such as coating different materials like wood, stainless steel, and glass; after coating, we checked the effect of watercolors, ink, and chemical resistance on stainless steel with three different chemicals: Sodium hydroxide, sodium chloride, and Sulfuric acid. Moreover, we perform the contact angle test with different chemicals to check the hydrophobic and hydrophilic properties of the coating material. Furthermore, we perform and calculate the value percentage for gel swell and gel content and check the effect of UV light on the NIPU films, which didn’t affect the films. By the observance of all the characterizations, we can make NIPU films with promising thermal and mechanical properties, along with an environmentally friendly and straightforward fabrication process, highlighting their potential for large-scale application.

Comments

This research is related to replace the traditional petroleum-based polymers with bio-based sustainable polymers for coating and adhesive with green approach.

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