By Maurice Morton
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Additional info for Anionic Polymerization: Principles and Practice
Were used as promoters 658 LiH, LiNH 2 A promoter is forr ned in situ by the reaction of 200-1400 ppm water in trle monomer with sufficient isocyanate to reduce water content to < 50 ppm 659 NaH, NaOMe at 145-175°C l-Chloro-3-oxoiso indolenine as a promoter 660 Na caprolactam salt at 120°C 661 ( NCN02 as polymerization accelerator.
1 Monomer Ethylene (continued) Double and Triple B«ond Monomers (continued) Initiator system r-BuLi/TMEDA at 0°C /-BuLi-TMEDA Acenaphthylene Acrylamide 36 Acrylamides (methyl substituted) (acrylamide, crotonamide, methacrylamide, N-methylacrylamide) Acrylonitrile «-BuLi in THF RLi in toluene ί-BuONa in o-dichlorobenzene at 120C BuLi, BuLi-TiCl4 at - 70°C 5-BuONa, (s-BuO)2Ca in aromatic sol vents, dioxane, pyridine, HCONMe 2 5-BuONa in polar solvents, such as pyridine, HCONMe 2, ΦΝ02 Alkali metal methoxides in methanol and in aprotic solvents ί-BuONa in TV-methyl-2-pyrrolidone at 100°C /-BuONa in aprotic solvents ί-BuONa in xylene at 50-60°C ί-BuOK in sulfolane at 100°C «-BuLi in pyridine at 110°C RLi, RNa, ROLi, RONa, Na naphthalene Remarks References Oligomerization at low pressure; the rate of consumption of ethylene depends on the pressure, ί-BuLi con centration, and TMEDA concentration; functionalized oligomers obtained by adding acetone at — 78°C Living polymer functionalized by addition of excess acetone at — 78°C Low molecular weight Crystalline, tactic polymer; high conversion High yields (95%) of poly(a-alanine) Polyacrylamide or a polymer containing poly(ß-alanine) unit were obtained Effect of solvents on chain structure 382, 383 384 385, 386 387 388 389 390 Effect of solvents on chain structure 391 Oligomerization reaction studied 392 Hydrogen transfer polymerization; branching in polymer studied Chain propagation mechanism High yield of poly(ß-alanine) Hydrogen transfer polymerization; mechanism Effect of methyl substituent on rate of polymerization and MW 393 Generally no termination; polymerization in nonsolvent limits molecular weight; high molecular weight polymer obtained in toluene or THF/DMF mixtures; some branched material formed 398-406 394 395 396 397 Acrylonitrile (continued) Bu 3Mg 2I in toluene BuMgCl in toluene at - 75°C Bu 3Mg 2I-DMF at 75°C Bu 2Mg, BuMgCl Bu 3Mg 2I RS Μ where Μ = Li, Na, or Κ BuLi in toluene at — 70°C Metal alkyls in hydrocarbon media 37 II ROC-S-M where Μ = Li, Na, K, and Zn in DMF at 0°C Et 3P in DMF Φ 3Ρ in DMF at 30°C BuLi, Li butyldipropylcarbinolate in toluene or DMF at low temperature BuLi in hexane and THF Dimsylsodium BuLi in toluene at — 75°C R 3P in HCONMe2 at 25°C Bu 3P Et 3P Diphenylsulfoxide potassium (1:1 or 1:2) in THF at -78°C Polybutadiene metal derivatives The activating effect of the Lewis bases HCONMe 2, Me2SO, and (Me 2N) 3PO was studied Kinetics study; termination free Catalytic effect of DMF Almost monodisperse polymer obtained Broad MWD due to the coexistence of different growing centers of polymerization Polymerization in both polar and nonpolar solvents ~50% of the initiator is used in the formation of acrylonitrile oligomers Oligomerization accounts for the low initiation efficiency The initiation ability of the xanthates increases with increasing basicity of the alcohol of the alkoxide group and with decreasing electronegativity of the metal ion 407 Polymerization via macrozwitterions Initiation by CH2 = C~ species 414 415 CN Low effectiveness of the catalyst due to side reaction 416 408 409 410 411 412 413 «-Butane formation and nitrile addition are important under these conditions MW < 20,000 Low efficiency of initiator due to oligomerization The effect of LiCl on the polymerization was studied Unsaturated oligomers obtained Kinetics and mechanism of polymerization Effective initiator 417 Block copolymer prepared 423 219 418 419 420 421 422 (table ?
Butane and conjugate addition products observed. 5%) was obtained with Κ in benzene. 3 Monomer Cyclic Monc )mers (Heterocyclics) Initiator system Remarks Re ferences Oxides Ethylene oxide Na, Κ catalysts in (Me 2N) 3PO Na, K, or Cs naphthalenes in THF + + + K , Cs , Na in Me2SO 52 Li naphthalene, Κ naphthalene, Κ bi phenyl, Κ anthracene, or di-K an thracene in Me2SO or THF Na, K, and Cs naphthalene in THF Na and Κ alcoholates of the monomethyl ether of diethylene glycol in (Me 2N) 3PO /-BuOK in Me 2SO Na naphthalene in THF r-BuOK in Me 2SO BuONa MeOK, MeONa, MeOLi Na alco'holate/alcohol Κ 4-(phenylazo)benzyl alcoholate Cs 3,6-dioxa-l-octanolate in Me 2SO at 50 C wa s Relation between M H V IGNand Mdeact ivated calculated and compared with experimental result Polymerization kinetics + + + Κ and Cs chain growth only via free ion; Na ion pairs also participated in the reaction; chain transfer to solvent No propagation occurred with Li naphthalene; polymers obtained for the other initiators 592 Strong association; living systems Association presence; reaction rate depressed by ΚΒΦ 4 596 597 Polymerization kinetics.