Producing lubricating base oils from coal-based chemicals is an alternative route for replacing the conventional petro-based lubricants. Herein, we firstly reported the synthesis of high-viscosity polyalkylphenanthrene oils derived from the coal-based chemicals (phenanthrene, C6/C8-olefins) by alkylation with acidic ionic liquid (Et₃NHCl∙2AlCl₃) as catalyst. Their primary physicochemical properties were studied in detail to reveal their structure–property relationships, the existence of the phenanthrene ring in their molecular structure led to some good property, such as high-kinematic viscosity (12.6–30.2 mm²·s⁻¹ at 100°C), better flash point (>230°C), high-oxidative onset time (>230°C) and good polarity. Moreover, the tribological performances of the synthetic oils and the commercial PAO-20 lubricating base oil were studied for comparison, these alkylated phenanthrenes, especially PHP-3 and POP-3, exhibited much higher load-carrying capacity, reducing friction and anti-wear property than that observed on PAO-20.

中文翻译：

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高粘度聚烷基菲油：润滑性能的合成和评价

用煤基化学品生产润滑油基础油是替代传统石油基润滑油的替代途径。_{在此，我们首先报道了以酸性离子液体（Et 3} NHCl∙2AlCl ₃）为催化剂，通过烷基化从煤基化学品（菲，C6/C8-烯烃）中合成高粘度聚烷基菲油。详细研究了它们的主要物理化学性质以揭示它们的结构-性质关系，其分子结构中菲环的存在导致了一些良好的性质，例如高运动粘度（12.6-30.2 mm ² ·s ^-1100°C)、更好的闪点 (>230°C)、高氧化起始时间 (>230°C) 和良好的极性。此外，为了比较合成油和商业 PAO-20 润滑基础油的摩擦学性能，这些烷基化菲，尤其是 PHP-3 和 POP-3，表现出更高的承载能力，减少摩擦和抗磨损比在 PAO-20 上观察到的性能。