Structure Design And Analysis Of Product Oil Drag Reducing Agent

With the rapid development of social economy and petrochemical industry,the demand for petroleum products is increasing.The pipeline transportation,as an important part of the transportation mode of petrochemical products,is also facing the pressure of full load operation.In order to achieve the purpose of reducing drag and increasing transmission,adding drag reducer in the pipeline is the most convenient and effective way.Therefore,it is of great economic and strategic value to develop drag reducer with good drag reduction effect and mild synthetic conditions.In this paper,the optimal conditions for the synthesis of ultra-high molecular weight polyolefin in Ziegler-Natta catalysis were studied by taking vinyl as the raw material.The effects of catalyst type and dosage,monomer concentration,solvent type and dosage,polymerization temperature,polymerization time and other factors on the molecular weight of the products were investigated.Through the method of control variables,the optimal conditions for the synthesis of polyolefins with ultra-high molecular weight were optimized as:the monomer dosage was 20 mL.Dosage of main catalyst 20 mg;the catalyst was triisobutyl aluminum(0.84 mL).The solvent was cyclohexane and the dosage was 30 mL.The polymerization temperature is 0?;the aggregation time was controlled for 48 h.The weight average molecular weight of the products can reach 2~3×106.The competitive polymerization of three kinds of polyolefin under optimal conditions was tested and a series of copolymers with different monomer ratios were synthesized.The molecular weight and structure of the products were characterized.The results showed that for the copolymerization of octene-hexene,r1=0.62,r2=0.79,and r1*r2=0.50;for for the copolymerization of decene-hexene r1=0.91,r2=1.4,r1*r2=1.27;for the copolymerization of decene-octene r1=0.71,r2=0.99,r1*r2=0.70.The monomer content in the copolymerization products can be controlled by adjusting the feed ratio.The weight average molecular weight of the products can reach 2~3×10~6,the composition of the copolymer is confirmed to be consistent with the material by the infrared spectrum and the nuclear magnetic carbon spectrum determines the belonging of carbon atoms in each position.DSC and XRD results show that the crystallization of the products can be reduced by copolymerization.The drag reduction performance of the synthesized product was tested by rotating disc equipment,and the influence of additive amount,molecular weight,Reynolds number,roughness and temperature on the drag reduction effect was investigated.The results show that the drag reduction rate increases first and then decreases with the addition of 5~300 ppm,while the drag reduction rate increases with the increase of molecular weight,Reynolds number,temperature and roughness.The polyolefin of one million molecular weight synthesized in this paper has a good drag reduction effect,in which the drag reduction rate of sample PDO-1-5reaches 22%under the addition of 10 ppm,which is better than that of domestic and foreign products under the same test conditions.