A Novel Approach to Synthesis Alkyd Resin from Recycled Polyethylene Terephthalate (rPET)

Abstract

Reducing carbon footprints is an essential requirement in the chemical industry. Researchers are concentrating on creating sustainable products derived from renewable resources or waste materials. Polyethylene terephthalate (PET) waste significantly contributes to carbon footprints; the chemical recycling of PET waste possesses extensive opportunities within the chemical sector. For instance, PET waste can be transformed into valuable alkyd resin, which is utilized in the production of oil-based paints. This research work focuses on the synthesis of long oil alkyd resin using recycled polyethylene terephthalate (rPET). As the incorporation of rPET in alkyd resin has several limitations such as two-step synthesis, inability to produce long oil alkyd, and long drying time. To overcome these limitations, a novel synthesis route has been devised to produce long oil alkyd resin. In this study, three long oil alkyd resins were synthesized, each containing varying amounts of rPET. The presence of rPET in the alkyd resins was confirmed by spectroscopic techniques. To assess the impact of rPET content on alkyd resin, physicochemical properties, performance testing, and instrumental analysis have been conducted. A comparison is made between these resins and the benchmark long oil alkyd resin, and the results are discussed. Furthermore, to synergize the coating applications, viscoelastic behavior and mechanical properties of the dried films were assessed, including exterior durability. Alkyd resin containing 8% rPET shows performance properties that are comparable to the benchmark alkyd resin. This alkyd requires 80 min for surface drying and 4 h to reach a tack-free state. It has a gloss value of 86 at 20° angle. The scratch hardness is recorded as 900 g, while the gloss retention stands at 88.34% following 240 h of QUV exposure. This novel synthesis route helps to incorporate the rPET in the alkyd backbone with reduced carbon footprint to meet the goal of sustainability and the circular economy.

Keywords

Recycling / rPET / Long oil alkyd / Sustainability / Circular economy

Acknowledgements

We express our sincere thanks towards the management of ‘Asian Paints limited’ to carried out this work. We are thankful to Ganesh Deokar, Subhajit Majhi and Ankit Joshi for carrying out the instrumental analysis. We are also thankful to Rajeevkumar Jain and Rajeevkumar Goel for giving us this opportunity.

Author Contributions

B.S.C.—Conceptualization, Methodology, Formal Analysis, validation, Writing Original Draft Preparation. V.S.—Supervision, Project Administration, Resources.

Ethics Statement

Not Applicable.

Informed Consent Statement

Not Applicable.

Availability of data and materials

Data will be made available on request.

Funding

This research received no external funding.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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