Polyethylene, synthesis

Lithocholic acid, structure of, 1082 Locant, IUPAC naming and, 87 Lone-pair electrons, 9 Loratadine, structure of, 206 Lotaustralin. structure of. 766 Low -density polyethylene, synthesis of, 1210... 

Screening of process conditions was one driver for performing polyethylene synthesis [1]. Thus, test-throughput frequency, the number of possible samples per day, is a target value. Also, flexibility with regard to temperature and pressure at low sample consumption is a major issue. In addition to fastness and flexibility, the quality of the information and the insight obtained is seen as a motivation for micro-channel studies. 

Abstract A -Heterocyclic carbene complexes produced on industrial scale are presented in this chapter along with a discussion about their production. Details of processes employing NHC complexes on pilot to industrial scales are discussed. These are frequently oriented towards the synthesis of biologically active molecules, however, examples are given for rubber formation and for 1-octene synthesis, a comonomer for polyethylene synthesis. 

TiCl4/MgCl2 catalysts may be used for the polyethylene synthesis, but not for the preparation of isotactic polypropylene. In fact, although these catalysts are highly reactive for the propylene polymerization, they are not stereospecific enough to give a commercially interesting product. 

Butane, pentane, and propane are also used as the reaction medium in polymer synthesis because carbon dioxide is not a strong solvent for most polymers. Furthermore, some polymerization reactions (such as polyethylene synthesis) are carried out under supercritical conditions of the monomer. 

A simplified schematic of a high-pressure polyethylene synthesis plant is illustrated in Figure 1. This scheme produces LDPE of density between 0.915 to 0.940 g/cc. The dashed lines on the diagram indicate heating control zones in the process. (Source Handbook of Polymer Science and Technology Volume 2 -... 

A change of the economic data and a higher demand of propene led to the closure of the plant in 1972. However, as it was relatively simple (see Figure 1), it could be restarted easily, probably not for obtaining but-2-ene but for the production of high purity but-l-ene, after treatment with an isomerization catalyst. Indeed, but-l-ene can be used as a comonomer in polyethylene synthesis. 

Von Hohenesche CF, Unger KK, Eberle T (2004) Agglomerated non-porous silica nanoparticles as model carriers in polyethylene synthesis. J Mol Cat A Chem 221 185-199 Kim YK, Lewis AF, Patra PK, Warner SB, Mhetre SK, Shah MA, Nam D (2002) Nanocomposite fibres. Mater Res Soc S5mp - Proc 740 441-446... 

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