Study On The Synthesis,Properties And Application Of Ultra-high Molecular Weight Poly-?-olefins

At present,the friction of the fluid in the pipeline and the formation of vortex in the pipeline transportation of crude oil and refined oil cause energy loss in the pipeline,which greatly increases the transportation cost.The use of ultra-high molecular weight long-chain poly-?-olefin as a drag reducer added to the fluid can significantly reduce the friction of the fluid in the pipeline,thereby increasing the efficiency of oil transportation.This article summarizes the development status of different types of drag reducers at home and abroad and their drag reduction mechanism,the preparation of polymer drags reducers,the development status of domestic and foreign polyolefin catalysts and the polymerization mechanism.Using ZieglerNatta catalyst Cat.1,a new synthetic amino-based titanium-based metal organic catalyst Cat.2 and a supported non-metallocene catalyst Cat.3 as the main catalyst for olefin polymerization,the preparation of ultra-high molecular weight ?-olefin polymerization used in oil pipeline transportation to reduce drag.The single factor experiment method was used to investigate the influence of the main catalyst and co-catalyst dosage,polymerization temperature and polymerization time on the monomer conversion rate and polymer molecular weight.It was found that the catalytic performance was the best when the Al/Ti ratio was 20 and the polymerization temperature was-10?.As the polymerization time increases,the polymerization monomer conversion rate increases.Use the viscosity average molecular weight test method to test the molecular weight of the polymer,and use FT-IR,NMR,XRD,POM and the indoor loop measurement system to test the polymer performance.Comparing the three catalysts,Cat.3 has the highest catalytic efficiency when catalyzing the polymerization of octene.Under the polymerization temperature of-10?,the polymerized monomers are completely converted,and the molecular weight of polyoctene is 5.47×106 g/mol,and its drag reduction efficiency reaches 31%.At the same time,the synthesized new amino-titanium metal organic catalyst also has excellent catalytic performance,and can obtain polyoctene with a molecular weight of 4.14×106 g/mol,and the catalyst has a simple synthesis process and low cost of raw materials required for production.High-molecular-weight poly-?-olefins are usually in a highly viscoelastic solid state at room temperature and cannot be added directly,and the solubility of the polymer in the solution is extremely low,and it cannot be prepared as an efficient drag reducer product.In order to obtain high-efficiency fluid drag reducer products that can be conveniently added to transportation pipelines,this paper proposes a suspension emulsion polydispersed system model based on the research of suspension and emulsion systems,and carries out the preparation formula of alcohol-based poly-?-olefin suspension emulsion Discussed.In the alcohol-based suspension emulsion polydispersed drag reducer using n-hexanol as the dispersion medium,the polymer content can be as high as 35 wt%.