This study has selected the medium-chain saturated fatty acid pelargonic acid as the raw material for the first time, and added the surface catalyst Tween 80 to the aqueous solution to form pelargonic acid–Tween 80 composite vesicles by a surface tension method. The compound vesicle was used to encapsulate five heterocyclic drugs (cefazolin sodium, chlorpromazine hydrochloride, gemcitabine hydrochloride, metronidazole, and isoniazid), all of which have disadvantages when used directly, and the effects of the vesicles on the five kinds of drugs were evaluated in terms of encapsulation rate and the in vitro sustained release in a simulated artificial intestinal fluid environment. The results revealed that the pelargonic acid–Tween 80 composite vesicles exhibit an encapsulation efficiency above 45%, and that the encapsulated drugs achieve a cumulative release effect of 6–10 h in a simulated artificial intestinal fluid environment, and the cumulative release rate is above 35%. This study proves that pelargonic acid–Tween 80 composite vesicles can be used as a carrier for encapsulated drugs, and this can extend the time of action of the drugs. This research illustrates the potential for application of pelargonic acid in the field of medicine.
Chemical oil esters synthesized by polyols and fatty acids are biodegradable and have ideal physicochemical and lubricating properties as compared to mineral lubricants. Using sulfuric acid and lipases as catalysts, a polyester lubricant was synthesized from pelargonic acid (PA) and trimethylolpropane (TMP). Lipase-catalyzed goods are superior and more in accordance with green production requirements. The optimized reaction conditions of lipase catalytic were 50 °C, 15%wt enzyme content, PA: TMP= 3.3:1 %, and 15 % water content. When the time reached 96 h, the accumulation of trimethylolpropane (TMPTP) reached 82% under these conditions. The TMPTP purified by molecular distillation has a flashpoint of 276 °C, a pour point of − 57 °C, and a viscosity index of 145, making it more suitable for extreme environments. On this basis, to improve the viscosity-temperature performance of the substrate, a certain proportion of oleic acid (OA) is added. Low viscosity (kinematic viscosity of 4.86–9.54 mm 2 /s at 100 °C), high viscosity index (VI > 160), low pour point (−50 °C), and low friction coefficient (COF) of 0.09 ∼ 0.11 is among the properties of a series of synthetic hetero-chain mixed esters, which can meet the needs of a variety of extremely low temperatures and complex working conditions.
Biolubricants produced by chemically modifying vegetable oils are promising to replace mineral-based lubricants. However, the performances of biolubricants synthesized through traditional chemical modification routes, such as transesterification/esterification, epoxidation with further ring opening, and estolide formation, cannot satisfy the demands of extreme conditions. Meanwhile, complicated multi-step reactions cause expensive costs, which hinders their large-scale application. In this study, pelargonic acid (PA) derived from the cleavage of oleic acid was esterified with trimethylolpropane (TMP) to produce branched-chain esters (tri-TMP esters) catalyzed by the lipase ( Candida sp. 99–125 ), focusing on batch stability of the lipase, thermal-oxidation stability and lubrication performance of the product. The lipase maintained high activity for 4 continuous batches in 5 L enzyme reactor with the conversion of PA > 96% and the accumulation of tri-TMP esters > 84% in each batch. The obtained tri-TMP esters had a pour point of − 56 °C, a viscosity index of 137, and a flash point of 276 °C. Anti-oxidation stability test and thermogravimetric behaviors showed that the biolubricant had favorable thermal-oxidative stability. Friction tests verified that the product displayed excellent lubrication performance with a minimum coefficient of friction (COF) of 0.099 and an average wear spot diameter (WSD) of 221.5 µm. The green and high-selective synthetic pathway fills the defect of existing routes for the preparation of biolubricants from chemically modified vegetable oils.
危险品化学品经营许可证（带存储）