In this work, the authors synthesized three different acrylates by esterification reaction of acrylic acid with long chain alcohols (octyl alcohol, decyl alcohol and dodecyl alcohol). Homopolymer of castor oil (CO) and three copolymers of castor oil with acrylates were synthesized by free radical polymerization using azobisisobutyronitrile (AIBN) as initiator. FT-IR and NMR spectral technique were used to characterize the synthesized polymers. The average molecular weight was determined by gel permeation chromatography (GPC). Thermo gravimetric analysis (TGA) method was used study the thermal behaviour of the 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 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，作者通过丙烯酸与长链醇（辛醇，癸醇和十二烷醇）的酯化反应合成了三种不同的丙烯酸酯。以偶氮二异丁腈（AIBN）为引发剂，通过自由基聚合反应合成了蓖麻油（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。通过凝胶渗透色谱法（GPC）测定平均分子量。使用热重分析（TGA）方法研究了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。