Novel nanohybrid pour point depressants (PPDs) were prepared by combining ethylene–vinyl acetate (EVA) copolymers with nano-SiO₂ particles, and a series of experiments were carried out to test the effects of EVA/nano-SiO₂ (E–S) hybrid PPDs on model waxy oil containing 25 wt % wax and crude oil. The results showed that optimal PPD performance was attained at the concentration of 0.08 wt %, which can suppress the formation of gelling effectively and improve the fluidity of both oils. The presence of the E–S hybrid PPD effectively modulated the crystal morphology to the orientation that was conducive toward reducing the gelling temperature and inhibiting the formation of the network structure. Meanwhile, the PPD adsorbed on the surface of asphaltene and resin can prohibit the self-association of asphaltene and resin, which further improved the fluidity of crude oil.

中文翻译：

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新型纳米混合降凝剂的评估和机理分析对促进原油流动性的影响

通过将乙烯-醋酸乙烯酯（EVA）共聚物与纳米SiO ₂颗粒结合制备新型纳米杂化降凝剂（PPD），并进行了一系列实验以测试EVA /纳米SiO _{2的作用。}（ES）包含25％（重量）蜡和原油的蜡质模型油的混合PPD。结果表明，在0.08 wt％的浓度下，可以获得最佳的PPD性能，可以有效抑制胶凝的形成并提高两种油的流动性。E–S杂化PPD的存在有效地将晶体形态调节到有利于降低胶凝温度和抑制网络结构形成的方向。同时，吸附在沥青质和树脂表面的PPD可以阻止沥青质和树脂的自缔合，从而进一步提高了原油的流动性。