Polyurethane Prepared from Neem Oil Polyesteramides for Self-Healing Anticorrosive Coatings

Abstract

Polymeric researchers desire strongly to reduce dependency on fossil or petroleum feed stock by utilizing renewable source based polymeric resins in coating. The present research represents the attempt made to develop neem oil (a renewable source) two-pack self-healing anticorrosive polyurethane (PU) coatings cured at room temperature. The oil-based polyesteramide was prepared in two steps; viz., in the first step, oil fatty amide was synthesized, and in the second, it was directly converted to polyesteramide by condensing amide with phthalic anhydride. A spectral study of prepared resin was carried by FT-IR and NMR techniques. Polyesteramide further was utilized for preparation of self-healing PU coatings with incorporation of polyamidoamine based polyurea microcapsules containing natural self-healing agent. The obtained coatings were tested for thermal, physicochemical, and corrosion resistance tests. The coating properties, like gloss, impact resistance, adhesion, and flexibility, were also studied and found to be superior for anticorrosive self-healing industrial coatings.

Eco-friendly polyurethane coatings from cottonseed and karanja oil

“…Vegetable oils are cheap, easily available, non-hazardous and most importantly biodegradable. Lot of reports available on vegetable oil based polymeric resins such as soybean oil [8], castor oil [9], neem oil [10], sunflower oil [11], linseed oil [12], jatropha oil [13], cottonseed oil [14], mahua oil [15], etc. The synthesis of polyesteramide and polyurethane coatings from fatty acids is also well documented [16,17].…”

Microencapsulation of quinoline as a corrosion inhibitor in polyurea microcapsules for application in anticorrosive PU coatings

“…However, this barrier itself cannot stop propagation of the corrosion process if the coating is somehow disturbed for any one reason [1]. Therefore, researchers have recently focused on development of coatings referred to as 'smart coatings' which sense the changes in the surrounding atmosphere and interact and respond to these changes in addition to their conventional decorative and protection roles [2]. The addition of organic corrosion inhibitor directly to the coating is one of the practices for enhancing corrosion protection ability of coatings.…”

Development of PU Coatings from Neem Oil Based Alkyds Prepared by the Monoglyceride Route

“…Applications of neem oil in the preparation of polymeric resins have already been documented in previous reports [20][21][22][23]. But the synthesis of various alkyd resins from neem oil using a monoglyceride (MG) route and their utilization for the preparation of PU coatings are reported here for the first time.…”