In this work, the authors synthesized three different acrylates by esterification reaction of acrylic acid with three different long chain alcohols (octan -1-ol, decan -1-ol and dodecan -1-ol). Homopolymer of castor oil (CO) and three copolymers of castor oil with acrylates were prepared by free radical polymerization method in the presence of azobisisobutyronitrile (AIBN) as initiator. FT-IR and NMR spectral technique were used to characterize the synthesized polymers. The number average molecular weight (M_n) and weight average molecular weight (M_w) were measured by gel permeation chromatography (GPC) method. Thermo gravimetric analysis (TGA) method was used to study the thermal behaviour of the prepared polymers at high temperature. Performances of the polymers as additives in lubricating oil were carefully assessed in terms of viscosity index and pour point. The experimental results showed that the prepared copolymers are better additives than homopolymer. Disc diffusion method was applied to carry out the biodegradability test of all the prepared polymers.

中文翻译：

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蓖麻油和丙烯酸酯基共聚物作为润滑油的绿色添加剂

在这项工作中，作者通过丙烯酸与三种不同的长链醇（辛烷-1-醇，癸烷-1-醇和十二烷-1-醇）的酯化反应合成了三种丙烯酸酯。在偶氮二异丁腈（AIBN）作为引发剂的条件下，通过自由基聚合法制备了蓖麻油（CO）的均聚物和蓖麻油与丙烯酸酯的三种共聚物。FT-IR和NMR光谱技术被用来表征合成的聚合物。数均分子量（M _n）和重均分子量（M _w）通过凝胶渗透色谱法（GPC）测量。热重分析（TGA）方法用于研究所制备的聚合物在高温下的热行为。根据粘度指数和倾点，仔细评估了聚合物作为润滑油添加剂的性能。实验结果表明，所制备的共聚物是比均聚物更好的添加剂。采用圆盘扩散法对所有制备的聚合物进行生物降解性测试。