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Since the development of electrostatic powder spraying, powders based on epoxy resins have been the ones predominantly used. These powders have worked well in many cases and can be used for decorative as well as functional coatings. These coatings due, to the chemical nature of epoxy resins, are ‘thermosetting’. This means they not only undergo a physical change when heated, that causes them to melt and flow but they also undergo a chemical change that causes them to increase in molecular weight or ‘crosslink’. Once this happens they cannot be remelted if heated a second time. Due to the wide use of epoxy powders many people associate powder coating with thermosetting powder.

More articles have been published about powder coating in the last two years than about any other phase of the protective coatings industry. From this almost overwhelming flurry of print, certain factors emerge. The first is that powder coating technology is certainly a valid and useful one. It has established itself as an integral contributor to the achievements of the protective coatings industry and, without doubt, it will be with us for many years to come. Its success is due to its many advantageous factors which have been reviewed many times in the past. Great strides have been made in that a highly versatile group of powders are now available with both thermoset and thermoplastic properties; it is possible to achieve thin coatings; and the savings in terms of effective powder usage have been well‐documented. Where there is overspray, equipment has been evolved for recycling. Stressed most often has been powder coating's contribution to a non‐polluting painting operation. Powder coating, on the other hand, does not solve the energy shortage problem since the coatings must be fused and baked. However, less energy is required than for solvent based coatings simply because the energy requirements associated with solvent removal are eliminated.

Summary Corrosion is not a new phenomenon. It is only recently, however, that the damage it causes has been fully recognised. The cost must not only be measured in the metal destroyed, but the enormous cost of replacement, maintenance and repair.

The Federation of Societies for Paint Technology authorised Levinson to do a study on powder coating, electrocoating and radiation. In an article [Journal of Paint Technology, July (1972) p. 37] Levinson describes the advantages and disadvantages of powder coating, the technology involved, the economics of the various systems, the relationship to ecology, the manufacture of powders, the resins which are useful, and future trends.

Modern powder coatings were introduced in 1952. They created great interest and much was written about them and much predicted for them. They did indeed find a niche, but they did not deliver quite as had been anticipated and by the early 1960's their star was waning. But one must never discount the impact of advancing technology — particularly when economy, convenience and performance are involved. Novel methods of application, primarily electrostatic spraying to complement the original fluidised bed approach, new formulations, faster curing epoxies and a better understanding of both the virtues and the defects of this method for industrial coating, has brought powder coatings back into their own.

The aim was not to perform a systematic review but firstly to search in PubMed, Science Direct, Scopus and Web of Science databases on the papers published in the last five years using tools for reviewing the statement of preferred information item for systematic reviews without focusing on a randomized analysis and secondly to perform a bibliometric analysis on the properties of films and coatings added of tocopherol for food packaging.

On January 24, 2022, information was sought on the properties of films and coatings added of tocopherol for use as food packaging published in PubMed, Science Direct, Scopus and Web of Science databases. Further analysis was performed using bibliometric indicators with the VOSviewer tool.

The searches returned 33 studies concerning the properties of films and coatings added of tocopherol for food packaging, which were analyzed together for a better understanding of the results. Data analysis using the VOSviewer tool allowed a better visualization and exploration of these words and the development of maps that showed the main links between the publications.

In the area of food science and technology, the development of polymers capable of promoting the extension of the shelf life of food products is sought, so the knowledge of the properties is vital for this research area since combining a biodegradable polymeric material with a natural antioxidant active is of great interest for modern society since they associate environmental preservation with food preservation.