Soybean oil

Soybean oil is obtained from the soybean, lat. Glycine max, which belongs to the Fabaceae family. It grows mainly in subtropical or tropical climates. It is an annual plant that grows about 30-100cm tall and is hairy on the stem and leaf. The soybean is similar in appearance to the German bush bean.

Depending on the variety, location and sun exposure, the oil content of the beans varies. On average, it contains about 20% of the dry weight of the beans in oil. It consists of 26% oleic, 49% linoleic and 11% linolenic acids and 14% saturated fatty acids. The percentage of free fatty acids is < 1%. It also contains 1.5 - 4% phospholipids (lecithin) and 0.8% stigmasterol, sitosterol and tocopherol. Phospholipids and sterols are removed by refining with alkalis. The light yellow oil is extracted from the cells by water and pressing. The smell of the oil has a pungent, nutty pleasant odor. The taste of the crude oil is described as varnish or grass-like. The flash point is 282°C, and the ignition point is 445°C. The saponification value is 189 - 195 (O'Neil MJ, Smith A, Heckelman PE, Obenchain JR, Gallipeau JAR & D'Arecca MA: Merck Index : An Encyclopedia of Chemicals, Drugs, and Biologicals, NJ (USA); 2562 pp, 2001). The double bond of the fatty acids contained can be saturated not only with hydrogen but also with oxygen. In this process, epoxides are formed, which represent a chemically reactive group in the molecule. The epoxidized soybean oil (SME; see below) obtained in this process is used exclusively in the processed industry.

The best known application of soybean oil, apart from its use in margarine, is its use in biodiesel. The chemically refined soybean oil used is soybean methyl ester (SME).
Soybean oil is often used in technology as a carrier or filler: a frequently mentioned example is the production of inks for printing print media. However, the oil can also be further chemically modified: Epoxidized soybean oil has been given its own CAS number (8013-07-8) due to its chemical reactivity and is used as an additive, stabilizer or plasticizer in various fields. These include: Coating products, fillers, putties, plasters, modeling compounds, adhesives and sealants, finger paints, polymers, and lubricants and greases.

The epoxidized soybean oil (ESBO) already mentioned is used, among other things, as a plasticizer for PVC compounds with a stabilizing effect. It is thus a vegetable-based product and an alternative to phthalic plasticizers. It is often used as a second plasticizer.
It improves the resistance of PVC to atmospheric influences and is therefore used, among other things, in the production of food packaging.

At KRAEMER, soybean oil alkyds are produced from soybean oil for the ecological wood coating industry and the production of coatings. In addition, soybean oil products from KRAEMER are also used in cavity sealants and wall paints.