The first important patents on synthetic resins were granted about 25 years ago. These patents covered phenolic resins probably intended for use as substitutes for certain natural resins. It was soon found that these synthetics offered possibilities of application vastly greater than the natural materials. At first progress in their application was slow as is usually the case with new products. During the World War the shortage of phenol promoted interest in the use of the other tar acids as raw materials for synthetic resins and intensive research developed resins from the cresols and higher boiling tar acids. These resins possessed properties sufficiently different from those made from phenol to establish them permanently.
In the meantime research on other types of resins was carried on in the United States and in Europe. The tar-acid resins for molding were the only commercially important ones on the market until about 1929. About that time, however, new commercial products began to appear rapidly. Cast phenolic resins became available as material for novelties of unusual brilliancy and beauty, the urea resins to meet the requirements for light colored thermosetting resins in molded articles, and the alkyd resins for use in new surface coatings which replaced conventional paint materials.
Later there followed a number of thermoplastic materials offering new and unusual properties. Vinyl resins found application in molded products and in safety glass. The acrylate resins became the nearest approach to organic glass yet developed. The polystyrene resins, long in the research stage, made their commercial appearance in 1937. Resins from petroleum, from furfural, from adipic acid, and from aniline are on the market. Many others are under investigation and some of them will undoubtedly become important.
The versatility of synthetic resins is most unusual. In various uses they have successfully displaced glass, wood, metal, hard rubber, bone, glue, cellulose plastics, protein plastics, and conventional paint materials. They compete with glass in shades and reflectors and offer properties which will increase their use for this purpose. Cases for scales, radios, and clocks, formerly of wood and metal, are now made of these synthetic resins.
Scope and purpose.
This survey deals with the synthetic resins, the nature and trade in the raw materials necessary for their production, the processes by which they are made, trade in them in the United States and between nations, and the nature of the competition which they meet. It does not go into the details of manufacture of and trade in the multitude of articles made of synthetic resins but stops at the point where these materials are turned over to the resin fabricator. The synthetic resins are but one of four broad groups of organic plastics. The others—natural resins, cellulose ethers and esters, and protein plastics—are discussed herein only as they relate to or compete with the synthetic resins.
The purpose of the survey is to bring together in one publication the available information on synthetic resins so as to provide a basis for consideration of future tariff problems. Because the industries involved are comparatively young and are expanding rapidly, their present day importance is not generally realized. The rapidity with which the synthetic resin industry is developing causes any comprehensive report on the subject to be practically out of date before it can be published. Notwithstanding the progress made each year in the quantity of production, new applications, and new commercial products, the industry may be said to be still in the industrial nursery. This circumstance necessarily limits the period during which any treatment of the subject will be representative.
Fundamental definitions.
The scope of this report has been stated to include synthetic resins up to the point where they are further manufactured, and the raw materials used in producing them. It was also stated that natural resins and synthetic plastics other than resins, such as the cellulose compounds and modified rubber compounds, are excluded. The boundaries of these categories are therefore important.[1]