3,6-二叔丁基咔唑在Ⅱ类基础油中的抗氧化性能

Antioxidant Properties of 3,6-Di-Tert-Butylcarbazole in Lube Base Oils Ⅱ

摘要:

以氯代叔丁烷为烷基化试剂，AlCl3为催化剂，在无水无氧条件下合成了3,6-二叔丁基咔唑，分离收率53%，并用1HNMR和13CNMR对产物的结构进行表征。将3,6-二叔丁基咔唑作为润滑油抗氧剂，将其与有机钼助剂钼酸酯（MoE）复配，以0.8%的质量分数加入Ⅱ类基础油中，用DSC动态法和旋转氧弹法（RPVOT）对其抗氧化性能进行了评价。DSC动态法结果显示：3,6-二叔丁基咔唑可以有效提高Ⅱ类基础油的氧化安定性和热稳定性，将起始氧化温度提高50.9℃；和MoE复配以后可以将起始氧化温度提高66.3℃；旋转氧弹法结果表明：3,6-二叔丁基咔唑可以将Ⅱ类基础油的氧化诱导期提高到2倍，和有机钼助剂复配后可以将氧化诱导期提高到2.5倍。油溶性测试表明：在咔唑苯环上引入叔丁基后提高了咔唑在Ⅱ类基础油中的溶解性。

Abstract:

3,6-Di-tert-butylcarbazole was synthesized under anhydrous and anaerobic condition by using 2-chloro-2-methylpropane as alkylation reagent and AlCl3 as catalyst with an isolated yield of 53%. The structure of the product was characterized by 1HNMR and 13CNMR. 3,6-Di-tert-butylcarbazole was used as an antioxidant agent of lubricating oil, and then it was compounded with an organic molybdenum addi-tive, organic molybdate (MoE) which was synthesized by our research group. Subsequently, 0.8% mass fraction of this compound was added into lube base oil II. The antioxidant performance of lube base oil II was evaluated by differential scanning calorimetry (DSC) dynamic method and rotary pressure vessel ox-idation test (RPVOT). DSC results showed that 3,6-di-tert-butylcarbazole effectively improved the oxida-tion stability and thermal stability of lube base oil II. The initial oxidation temperature of the sample by adding 3,6-di-tert-butylcarbazole was increased by 50.9℃, while that of lube base oil II by adding the compound of 3,6-di-tert-butylcarbazole and MoE was increased by 66.3℃. RPVOT results revealed that 3,6-di-tert-butylcarbazole could increase the oxidation induction period of lube base oil II to 2 times, the compound of it and MoE could increase the oxidation induction period to 2.5 times. The oil solubility test displayed that the introduction of tert-butyl groups on the carbazole benzene ring increased the solubility of carbazole in lube base oil II.