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The development of environmentally friendly coatings is imperative in today’s context of sustainability. Bio-based coatings, particularly those formulated in waterborne systems, offer a promising avenue for reducing environmental impact while maintaining performance standards. This article explores the progress made in biobased coatings, focusing on synthesis pathways and the utilization of monomers derived from renewable resources [1].

Synthesis routes for waterborne bio-based coatings

Waterborne coatings are formulations where water serves as the primary solvent, reducing the need for volatile organic compounds (VOCs) and minimizing environmental pollution. In the synthesis of bio-based coatings, various routes are employed to incorporate renewable feedstocks [2]. These pathways include polymerization of bio-based monomers, modification of existing polymers with biobased additives, and the development of novel bio-based resins.

Utilization of Monomers from Renewable Resources

Renewable resources such as plant oils, bioethanol, sugars, and lignin derivatives serve as feedstocks for producing bio-based monomers. Plant oils, for instance, can be converted into epoxidized oils or fatty acids, which act as reactive precursors in coating formulations. Bioethanol, derived from biomass fermentation, offers a sustainable alternative to petroleum-derived solvents and monomers [3]. Similarly, sugars derived from biomass can undergo fermentation or chemical conversion to yield monomers like lactic acid, which find applications in bio-based coatings. Lignin, a byproduct of the pulp and paper industry, presents opportunities for valorization into phenolic compounds and aromatic monomers, enhancing the sustainability of coating formulations.

Advantages of bio-based coatings in waterborne systems

Waterborne bio-based coatings offer several advantages over their conventional counterparts. They exhibit lower VOC emissions, reduced toxicity, and improved eco-friendliness, aligning with stringent environmental regulations and consumer preferences. Moreover, biobased coatings contribute to the reduction of fossil fuel dependence and promote the utilization of renewable feedstocks, fostering a circular economy approach.

Waterborne bio-based polyurethane coating

Polyurethane (PU) is a very versatile polymer that is commonly produced through the polyaddition of polyols and isocyanates . Polyols constitute the soft segment of PU which gives flexibility, while isocyanate and chain extender tend to form hard segment that provide rigidity and stiffness to the polymer [4-6]. Final properties of the PU can be tailored depending on the types and ratios of polyols and isocyanates in the formulation, types of additives, and manufacturing process. Due to the

Waterborne bio-based polyester coating

Linear polyesters are generally produced from polycondensation of diols and dicarboxylic acids, while branched polyesters are from monomers with higher functionality. By varying the types of diols and diacids used in the formulation, polyesters with different properties suitable for wide range of applications can be formulated. Examples include the reported use of polyester as coatings, textiles, laminates, and biomedical materials . Polyester coatings are

Waterborne bio-based epoxy coatings

Epoxy coating is a thermosetting polymer comprised of epoxy monomers and hardeners. It is well known for its strong adhesion to various substrates, excellent chemical resistance, and mechanical properties, rendering it suitable to be used as coating in many applications. A common epoxy monomer is diglycidyl ether bisphenol A (DGEBA) produced from the reaction between petroleum-based epichlorohydrin and bisphenol-A (BPA). However, health hazard associated with leaching of BPA from polymeric.

Challenges and future directions

Despite the progress in waterborne bio-based coatings, certain challenges persist. Issues such as cost competitiveness, performance limitations, and scalability hinder widespread adoption in industrial applications [7-10]. Additionally, achieving compatibility with existing coating technologies and addressing durability concerns are areas that require further research and development efforts. Future directions in this field include exploring advanced synthesis techniques, optimizing formulation parameters, and enhancing the understanding of structureproperty relationships to tailor coatings for specific applications.

Conclusion

The evolution of waterborne bio-based coatings represents a significant step towards sustainable coating solutions. By leveraging renewable resources and innovative synthesis routes, these coatings offer a viable alternative to traditional petroleum-based counterparts. As research continues to drive advancements in formulation strategies and material design, waterborne bio-based coatings are poised to play a pivotal role in meeting the demands for environmentally conscious coatings across various industries.

1. Tarkowski E, Tullberg M, Fredman P (2003)Neurobiol Aging 24: 707-714.

, ,

2. Urzi F, Pokorny B, Buzan E (2020). Front Genet 11: 615238.

, ,

3. Starkweather AR, Witek-Janusek L, Nockels RP, Peterson J, Mathews HL (2008). J Neurosci Nurs 40: 32-39.

, ,

4. Bauer JM, Verlaan S, Bautmans I, Brandt K, Donini LM, et al. (2015)J Am Med Dir Assoc 16: 740-747.

, ,

5. Inose H, Yamada T, Hirai T, Yoshii T, Abe Y, et al.( 2018). Osteoporosis and Sarcopenia 4: 33-36.

, ,

6. DigheDeo D, Shah A (1998).J ECT 14: 115-119.

,

7. Takahashi S, Mizukami K, Yasuno F, Asada T (2009). Psychogeriatrics 9: 56-61.

, , Crossref

8. Bellgrove MA, Chambers CD, Vance A, Hall N, Karamitsios M, et al. (2006). Psychol Med 36: 495-505.

, , Crossref

9. Carter CS, Barch DM (2007). Schizophr Bull 33: 1131-1137.

, ,

10. Gupta S, Fenves AZ, Hootkins R (2016). Clin J Am Soc Nephrol 11: 1872-1878.

, ,