發(fā)布時間：2018-05-09 04:26

  本文選題：三羥甲基丙烷油酸酯 + 氧化��； 參考：《機械科學研究總院》2015年碩士論文

【摘要】：本文以國家“973”課題“潤滑添加劑的減摩抗氧化特性及其對合成潤滑油使役行為的作用規(guī)律”為依托,系統(tǒng)測試表征了酯類基礎(chǔ)油三羥甲基丙烷油酸酯(縮寫TMPTO)、偏苯三酸三異癸酯(縮寫TDTM)和己二酸二異辛酯(縮寫DEHA)的理化性能、熱氧化性能和摩擦學性能;運用紅外光譜和激光拉曼光譜方法深入研究了溫度、氧氣以及金屬催化對TMPTO化學結(jié)構(gòu)的作用,探討了TMPTO分子結(jié)構(gòu)變化與其理化性能、熱氧化性能退化的關(guān)聯(lián)規(guī)律;在從分子尺度揭示TMPTO基礎(chǔ)油熱氧化失效機制的基礎(chǔ)上,導入功能抗氧劑來阻斷體系中TMPTO化學結(jié)構(gòu)的氧化,提出了延長TMPTO基礎(chǔ)油高溫使用壽命的建議。論文的主要成果及結(jié)論如下:在熱氧化過程中,TDTM基礎(chǔ)油的氧化安定性好,其運動粘度、總酸值和粘度指數(shù)都表現(xiàn)出較好的穩(wěn)定性;DEHA基礎(chǔ)油的總酸值增長最顯著;TMPTO基礎(chǔ)油的運動粘度增長較快,隨著氧化時間的延長,TMPTO基礎(chǔ)油的運動粘度呈現(xiàn)指數(shù)關(guān)系增大,其總酸值呈現(xiàn)線性關(guān)系增大;隨著氧化時間的延長,TMPTO和DEHA基礎(chǔ)油的粘度指數(shù)呈現(xiàn)降低趨勢;TMPTO基礎(chǔ)油的摩擦學性能優(yōu)于DEHA基礎(chǔ)油和TDTM基礎(chǔ)油。首次通過TMPTO基礎(chǔ)油原位熱氧化的拉曼光譜分析發(fā)現(xiàn),隨著氧化溫度的升高,TMPTO基礎(chǔ)油的主要結(jié)構(gòu)組成(=C-H、C=C以及-CH2-)的拉曼峰強降低,C=C伸縮振動峰的拉曼位移線性增大;冷卻至室溫后,=C-H和C=C的拉曼峰強可部分恢復(fù),-CH2-則完全恢復(fù),C=C伸縮振動峰的頻移完全消失。隨著熱氧化時間延長,TMPTO分子結(jié)構(gòu)中=C-H可完全消耗,C=C可部分消耗;C=C的化學變化過程遵循一級反應(yīng)動力學,其反應(yīng)速率常數(shù)受單位體積油品的溶氧量影響顯著。金屬催化實驗表明,Fe的催化作用明顯加劇TMPTO基礎(chǔ)油理化性能和熱氧化性能的惡化,Cu其次,Al最小;與玻璃容器相比,Fe的催化作用會明顯增大TMPTO碳碳雙鍵的一級反應(yīng)速率常數(shù)。在95℃和135℃氧化條件下,適量的抗氧劑L115和T558能夠較好地抑制TMPTO基礎(chǔ)油運動粘度和總酸值的增長;在175℃和250℃氧化條件下,胺類抗氧劑T558以及胺類T557、T558與酚類T502的復(fù)配抗氧劑能夠較好的抑制TMPTO基礎(chǔ)油運動粘度和總酸值的增長。研究發(fā)現(xiàn),氧化穩(wěn)定性評價方法(高壓差示掃描量熱法PDSC、旋轉(zhuǎn)氧彈法RBOT)的測試原理差異,對抗氧劑改進TMPTO基礎(chǔ)油抗氧化性能的表征有很大影響,可導致相同試驗溫度下截然相反的氧化誘導時間數(shù)據(jù)。在PDSC試驗中,胺類抗氧劑的改進作用優(yōu)于酚類抗氧劑,在RBOT試驗中,酚類抗氧劑的改進作用優(yōu)于胺類抗氧劑。
[Abstract]:This paper is based on the national "973" project, "antifriction and antioxidation characteristics of lubricating additives and their effects on the behavior of synthetic lubricating oils". The physical and chemical properties, thermal oxidation and tribological properties of ester base oil trimethylol propane oleate (TMPTOA), triisodecyl trimethylate (TDTM) and diisooctyl adipate (DEHAA) were investigated. The effects of temperature, oxygen and metal catalysis on the chemical structure of TMPTO were studied by means of infrared spectroscopy and laser Raman spectroscopy. The relationship between the molecular structure of TMPTO and its physical and chemical properties and thermal oxidation degradation was discussed. On the basis of revealing the failure mechanism of thermal oxidation of TMPTO base oil on molecular scale, functional antioxidants were introduced to block the oxidation of TMPTO chemical structure in the system, and some suggestions for prolonging the high temperature service life of TMPTO base oil were put forward. The main results and conclusions are as follows: in the process of thermal oxidation, TDTM base oil has good oxidation stability and kinematic viscosity. The total acid value and viscosity index showed good stability. The increase of total acid value of DEHA base oil was the most significant. The kinematic viscosity of TMPTO base oil increased rapidly, and the kinematic viscosity of TMPTO base oil increased with the extension of oxidation time. With the increase of oxidation time, the viscosity index of TMPTO and DEHA base oil decreased. The tribological properties of TMPTO base oil were better than that of DEHA base oil and TDTM base oil. Raman spectroscopy analysis of in-situ thermal oxidation of TMPTO base oil shows for the first time that the Raman peak intensity decreases linearly with the increase of oxidation temperature, and the Raman shift increases linearly with the increase of oxidation temperature. After cooling to room temperature, the Raman peaks of C H and C C can be partially recovered and the frequency shift of the stretching vibration peaks of C C can be completely recovered. With the prolongation of the thermal oxidation time, the chemical change process of TMPTO molecular structure in which the C ~ (- H) can completely consume C ~ (2 +) can partially consume C ~ (2 +) C follows the first-order reaction kinetics, and its reaction rate constant is significantly affected by the dissolved oxygen content of the unit volume of oil. The results of metal catalytic experiments showed that the degradation of physical and chemical properties and thermal oxidation properties of TMPTO base oils was obviously aggravated by the catalytic action of Fe, and the first order reaction rate constant of TMPTO carbon / carbon double bonds was increased obviously compared with that of glass containers. Under the oxidation conditions of 95 鈩，

本文編號：1864586