发泡处理对EVA树脂作为油田防蜡剂释放性能的影响

Effect of Foaming Treatment on Release Performance of EVA Resin as Oilfield Wax Inhibitor

对乙烯-乙酸乙烯酯共聚物(EVA)防蜡剂进行了化学发泡处理,研究了发泡剂和成核剂对EVA防蜡剂泡孔结构的影响以及泡孔结构与释放性能的关系。结果表明,当发泡剂偶氮二甲酰胺(AC)的用量在0.1~1.2 phr之间,随着AC用量的增多,泡孔平均直径和密度逐渐增大,泡孔平均直径与释放速率之间存在一定的指数关系。当AC的用量增加至1.5 phr,泡孔平均直径进一步增大,泡孔密度减小,释放速率减慢;经成核剂纳米碳酸钙(Nano-CaCO_(3))处理得到的防蜡剂样品的泡孔形态保留完整,主要以开孔结构为主,在油相中的释放速率最快;当AC的用量恒为1.2 phr,随着Nano-CaCO_(3)用量的增多,泡孔的密度逐渐增大,样品中的泡孔几乎均为开孔结构,释放速率逐渐加快,而当Nano-CaCO_(3)的用量继续增加至7 phr,泡孔出现塌陷,释放速率减慢。

The wax inhibitor of ethylene-vinyl acetate copolymer(EVA)was chemically foamed.The effects of foaming agent and nucleating agent on the cell structure of EVA wax inhibitor and the relationship between cell structure and release performance were studied.The experimental results show when the amount of foaming agent azodicarbonamide(AC)is between 0.1 and 1.2 phr,the average diameter and density of the cell gradually increase with the increase of the amount of AC,and there is an exponential relationship between the average diameter of the cell and the release rate.When the amount of AC increases to 1.5 phr,the average diameter of the cell further increases,the cell density decreases,and the release rate slows down.The foam morphology of the wax inhibitor sample treated with nucleating agent Nano-CaCO_(3),remains intact,mainly with open cell structure,and its release rate is the fastest in the oil phase.When the amount of AC is always 1.2 phr,with the increase of the amount of Nano-CaCO_(3),the cell density gradually increases.The cells in the sample are almost all open cell structures,and the release rate gradually increases.When the amount of Nano-CaCO_(3)continues to increase to 7 phr,the cells collapse,and the release rate slows down.