The Comparison Of Poly-α-olefins Between Bulk Polymerization And Solvent Polymerization Of The Oil-soluble Drag Reducer And Research On Prepolymerization

The drag reduction agent (DRA) that we have studied is a kind of ultra-high molecular polymers. The friction resistance can be decreased when DRA is added into the oil transportation pipes. That can save energy, having the important economic meaning. In this paper,the author briefly introduces the development of drag reduction all over the world and the polymerization method of drag reduction agent and the mechanism of drag reduction. Moreover, the procedure that usingα-olefin as material to synthesize DRA and the apparatus and the capability of DRA have been introduced.In this paper, I introduced the bulk polymerization solution polymerization Comparative Study results , and two of the programme pre-polymerization , pre-polymerization Orthogonal .In bulk polymerization and comparative study of the solution polymerization , the polymerization in bulk and n-heptane solution ( with solvent to volume ratio 3:2 ) of commercial C₁₀～C₁₄α-olefines containing >94% (v/v) C12 is investigated by using a two-stage reaction method in an atmospheric reator I with TiCl₃/MgCl₂ +Al(i-Bu)₃ as catalyst and DDS regulator and the polymerzation products are tested in diesel oil at 20℃for turbulent drag reduction (DR). The strring electric current , that is the viscosity , and the temperature of solution polymerization mixtures raise faster at starting reaction temperature (SRT) being of - 2 and - 4℃and slower at SRT=5℃(and 10℃) than that of bulk polymerization mixtuers ; the solution polymerization is affected by SRT and hence is more opercentage DR of solution polymerization products is lower at SRT≤-2℃and higher at SRT≥0℃than that of bulk polymerzationg products and is decreased nearly to zero after shearing 8 times in a simulation loop apparatus for evaluating drag reducers with 17 meters long working pipelines by contrast to 4 times for bulk polymerization products . The structural characteristics Mn , Mw , and Mw/Mn determined by GPC method are as follow : 2.10×10⁶ , 5.06×10⁶ , and 2.41 for a poly-α-olefine sample produced by solution polymerization in a pilot installation and 1.47×10⁶ , 3.99×10⁶ , 2.71 for a pilot bulk poly-α-olefine sample ; the solution polymer has higher relative molecular mass and more narrow distribution than of bulk one . The percentage DR of the two samples is of 41.27% and 43.79% , respectively. Without consideration on the later disposal of drag reducing agent (DRA) and the cost of solvent, solvent polymerization has a certain advantage over bulk polymerization .Projectâ… on bulk prepolymerization , synthesis of projectâ… is similar with bulk polymerization , was adopted . Adding before reaction solution into the reactorâ…¡. It adds monomer and accessorial catalyst in turn as Projectâ…¡, understanding of the factors affecting bulk pre-polymerization . It can be known through Projectâ…¡: (1) The increase over time of pre-polymerization, DR increases ; (2) With the accession to the increase in monomer of the main pre-polymerization, DR increases . In order to determine bulk pre-polymerization′s impact on various factors , I has selected four factors : time of pre-polymerization , followed by accession to the ratio of monomer , followed by accession to the ratio of accessorial catalyst , DDS pre-accession or DDS later joined . According to the four factors design orthogonal experiment . Orthogonal test results show that time of pre-polymerization and DDS pre-accession or DDS later joined are the main factors ,that followed by accession to the ratio of monomer and accessorial catalyst are secondary factors .