Page 149 - 摩擦学学报2025年第5期

第 5 期 杨珊珊, 等: 新型聚羟基脂肪酸酯基环境友好型润滑脂的制备及性能研究 783

discover a new type of green thickener to broaden the application range of renewable and biodegradable materials in
lubricating grease preparation. We had found that poly (3-hydroxybutyrate-co-4-hydroxybutyrate) (P34HB) possessed
biodegradability, gel-forming ability and excellent mechanical properties by consulting literature. It was a promising
petroleum-based material substitute in various fields. Moreover, in various fields of study, we had observed a remarkable
similarity between the microstructure of the P34HB material employed for sample preparation and that of conventional
lithium-based greases. For instance, electrospun P34HB exhibited a fibrous architecture. Collectively, we positted that
the P34HB material exhibited potential for augmenting the viscosity of base oil. In this study, a range of novel greases
with varying concentrations of P34HB as the thickener and castor oil as the base oil was prepared. The impacts of
different thickener concentrations on physicochemical, rheological, and tribological properties were comprehensively
investigated. The findings demonstrated that the colloid stability and oxidation stability of P34HB lubricating grease
improved with an increase in thickening agent content. The SEM analysis revealed that the microstructure of the P34HB
grease thickener differed from the fiber helical structure observed in lithium-based grease, exhibiting an irregular
stacking sheet structure akin to bentonite and certain polyurea greases. The formation of this form might be attributed to
the hydrogen bonding between P34HB and castor oil, as evidenced by the Fourier infrared spectrum and Raman spectral
analysis. This interaction leaded to irregular accumulation and aggregation of sheet materials, thereby impeding the flow
of base oil. The rheological property test results additionally demonstrated that the P34HB grease system exhibited
2
shear-thinning behavior and adhered to the Carreau Yasuda model (R >0.999), thereby confirming its non-Newtonian
properties akin to conventional greases available in the market. Additionally, the friction behavior results demonstrated
that under mild friction conditions, the P34HB lubricating grease with a thickening agent content of 48% demonstrated
frictional properties comparable to the control group, castor oil lithium-based grease. The preliminary analysis results of
the lubrication mechanism of P34HB, combined with SEM and XPS techniques, revealled that the thickener
microstructure in the P34HB grease system exhibited a relatively thinner sheet-like morphology (with a thickness less
than 100 nm). Consequently, it could be inferred that during the friction process, a significant number of small-sized
sheet structures were continuously transferred to the surface of the friction pair through the base oil under frictional
forces. This transfer effectively supported and maintained an adequate thickness of the oil film within the contact area,
working synergistically with subsequent chemical reaction films to provide lubrication. This study provided an effective
strategy for the application of P34HB in the lubrication field and paved the way for the development of a new generation
of environmentally friendly lubricating greases.
Key words: novel thickener; environmentally friendly; Poly 3-hydroxybutyrate-4-hydroxybutyrate; castor oil; grease

2024年，全球润滑脂市场规模达到了26.2亿升， 可降解润滑脂，所制备的润滑脂具有非牛顿流体特
预计2029年将达到30.8亿升，复合年增长率(CAGR)为 性，但其熔点较低，不适用于高温润滑. 另如Núñez等 [12]
[1]
3.38% . 润滑脂在润滑剂市场中占据着重要地位，广 使用不同类型的纤维素和蓖麻油制备可生物降解润
泛应用于交通运输、农业、烟草产品和医药机械等多 滑脂，所制备的油凝胶分散体的分解温度比对照组润
[2]
个领域 . 然而，大多数石油类皂基润滑脂的泄漏会造 滑脂高，但机械稳定性差. 因此，有必要不断探索研究
成相应的环境污染，与石油基材料相比，生物基材料 其他生物基稠化剂的性能，以便开发新的生物可降解
具有成本低、种类繁多、绿色环保以及可降解等优 润滑脂，拓宽生物基稠化剂制备环境友好型润滑脂的
势，符合国家绿色低碳及可持续发展道路 . 因此，采 范围，进而推动可再生材料替代石化材料的进程.
[3]
用生物基 材料作为石油材料的替代品来制备环境友 聚羟基脂肪酸酯(PHA)是1类由微生物合成的细
[4]
好型润滑脂是解决环境污染问题的有效途径之一. 如 胞内高分子聚酯，具有良好的生物相容性、结构多样
今润滑脂行业仍是以锂基润滑脂为主，占市场份额的 性、可生物降解性和成本较低等优点，被广泛应用于
[5]
[13]
70% . 植物油制备可生物降解润滑脂正在被广泛研 食品包装、纺织、组织工程以及生物医学材料等领域 .
究，其中对于利用生物基类型稠化剂制备环境友好型 PHA具有在有氧和无氧条件下实现生物降解的特性，
润滑脂的研究则是关注度较高的研究热点之一. 目前， 被视为聚乙烯、聚丙烯和聚对苯二甲酸乙二醇酯等化
[6]
研究中的可生物降解稠化剂包括不同种类的蜡 、纤 学塑料的优质替代品，有望解决不可降解原料带来的
[10]
[9]
[7]
[14]
[8]
维素及其衍生物 、聚丙烯 、壳聚糖 和海泡石 等. 污染问题 . 随着工业化快速发展，许多企业成功地
[11]
例如Radulescu等 以菜籽油和蜂蜡为基础制备生物 进行了PHA的规模化生产，预计全球PHA生产将不断