C20C40ketjuja
C20C40ketjuja is a term found in Finnish-language chemistry and materials science literature used to describe hydrocarbon chains whose carbon atom count falls roughly between 20 and 40. The notation draws on the C20 to C40 range, while ketjuja is the Finnish plural for chains. The term is typically used to refer to long-chain hydrocarbons that can occur as straight-chain alkanes (n-alkanes) or as branched structures, and it may appear in both natural petroleum fractions and synthetic products.
In practice, C20-C40 chains are associated with materials that have higher boiling points and greater viscosity
Properties and processing considerations stem from the chain length: longer chains lead to higher melting points
See also: hydrocarbon chain, alkanes, paraffin wax, lubricant basestocks, petroleum fractions. Further reading on hydrocarbon chain