Utjecaj dugolančanog i razgranatog alkohola na mazivost estera na bazi dodekandiojske kiseline

Abstract

Thirteen samples of esters based on dodecanedioic acid with different chemical structures were synthesized. Among these were di-2-octyl dodecanedioate, didecyl dodecanedioate, di-2-ethylhexanol dodecanedioate, di-2-ethylbutyl dodecanedioate, dioctyl dodecanedioate, dihexyl dodecanedioate, and dioleyl dodecanedioate. Diesters were synthesized through the esterification of dodecanedioic acid with selected long-chain and branched alcohols with acid catalyst of H 2 SO 4. These esters were tested in terms of their suitability for application as lubricants. The results showed that the lubricity properties, based on their pour point, flash point, and oxidation stability of the esters were significantly affected by the linear and branched alcohols used. An excellent pour point property of di-2-ethylbutyl dodecanedioate and di-2-ethylhexanol dodecanedioate at −55 °C and −50 °C was observed compared to their respective same linear carbon number esters of dihexyl dodecanedioate at 10 °C and dioctyl dodecanedioate at 20 °C. These are due to the presence of the branched group in their molecule vicinity structure. However, the esters flash points were insignificantly affected by the presence of branched structure. The selected esters could be used for biolubricants or engine oil.Sintetizirano je trinaest uzoraka estera na bazi dodekandiojske kiseline različitih kemijskih struktura. Među njima su bili di-2-oktil dodekandioat, didecil dodekandioat, di-2-etilheksanol dodekandioat, di-2-etilbutil dodekandioat, dioktil dodekandioat, diheksil dodekandioat i dioleil dodekandioat. Diesteri su sintetizirani esterifikacijom dodekandiojske kiseline s odabranim dugolančanim i razgranatim alkoholima s kiselinskim katalizatorom H 2 SO 4. Ti su esteri ispitani u smislu njihove prikladnosti za primjenu kao maziva. Rezultati su pokazali da su na svojstva mazivosti, temeljena na njihovoj točki tečenja, točki zapaljenja i oksidacijskoj stabilnosti estera, znatno utjecali upotrijebljeni linearni i razgranati alkoholi. Uočeno je izvrsno svojstvo točke tečenja di-2-etilbutil dodekandioata i di-2-etilheksanol dodekandioata pri −55 °C i −50 °C u usporedbi s njihovim istim ravnopravnim esterima ugljikova broja diheksil dodekandioata pri 10 °C i dioktil dodekandioata pri 20 °C, zbog prisutnosti razgranate skupine u strukturi njihove blizine molekule. Međutim, prisutnost razgranate strukture neznatno je utjecala na točke zapaljenja estera. Odabrani esteri mogli bi se rabiti za biomaziva ili motorno ulje.