Ethylene imine, polymerization

Similarly, ethylene imine polymerizes quite readily in the presence of cationic initiators (see Eq. 2.46). 

Ethylene is polymerized with good activity by both Zr and Ti phenoxy-imines to high molecular weight polymer, Mv — 104-106. Activity increases with increasing steric bulk at... 

A variety of methods for immobilizing polymerized liposomes have been reported. Multiple layers of vesicles were deposited on quartz slides by layer-by-layer assembly (Su 2005). The slides were first coated with a layer of poly(ethylene imine), a... 

In contrast, similar examination of the product obtained by template polymerization of acrylic acid on poly(ethylene imine), using electrophoresis, leads to the conclusion that in this case graft copolymer is absent. 

Paper chromatography was also used to separate the complex obtained by polymerization of acrylic acid in the presence of poly(ethylene imine). In this case, both the complex obtained by mixing of two polymers and the complex obtained in template polymerization gave two distinct spots. No trace was found of any graft copolymer. 

Scheme I Synthesis of hyperbranched poly(ethylene imine) (PEI) via acid catalyzed ring-opening polymerization of aziridine. Each color represents a different branching unit blue for linear units (L), black for dendritic units (D), red for terminal units (T). PEI has a degree of branching (DB) of 62-73%, the depicted structure represents only a small idealized fragment. Reproduced with permission from [91]...

Table 1.B Characterization of Combburst poly(ethylene imine) [89]a (polymeric dendrimer)...

Poly(N-alkyl-ethylene imine) can be prepared by cationic ring-opening polymerization of N-alkylaziridines however, branched polymers are obtained by this way 19>. Linear poly-MEI may be obtained by N-methylation of linear PEI by the Clarke-Eschiweiler variation of the Leukart reaction, in which an excess of formic acid is used together with formaldehyde. The reaction may be performed either on PEI, or... 

Poly(imines) are polymers that contain in their backbone amino nitrogens connected by single bonds to carbon atoms. Some of these polymers have a simple structure like poly(ethylene imine) or [-CH2-CH2-NH-]n. The polymer is obtained from the polymerization of aziridine, typically generating a mix of linear and branched macromolecules with about 25% primary amine groups, 50% secondary amine groups, and 25% tertiary amine groups. The polymer is used in paper industry and for various other purposes that make use of its anionic character [1]. 

The use of triallyl phosphate together with bromoform and a small imount of polyvinyl alcohol as the components of a phosphorus-containing aolymer which is formed on heat curing, has been recommended (Frick, A eaver, and Reid, Text. Res.J., 1955,25,100). These components may ilso be used in conjunction with THPC (Reid et al, Text. Res.J., 1956,26, 41). Trisaziridinylphosphine oxide (APO), obtained by the action of phos-)horyi chloride on ethylene imine, has been used to co-polymerize with TFIPC ... 

It is possible to prepare block copolymers by free-radical initiation, as R. B. Seymour, G. A. Stahl, D. R. Owent, and H. Wood discuss in their chapter. Methyl methacrylate macroradicals were made with peroxide and azo initiators in diluents, and different vinyl monomers were polymerized onto them. Block copolymers of two ethylene imines, one having a long (lauroyl) side chain and one with a short (propionyl) side chain were synthesized by M. H. Litt and T. Matsuda in a two-step cationic polymerization process. Block and random copolymers of episulfides were prepared by E. Cernia, A. Roggero, A. Mazzei, and M. Bruzzone using anionic catalysts of metalated sulfoxides and sulfones. 

EXPLOSION and FIRE CONCERNS dangerous fire and explosion hazard extremely flammable liquid NFPA rating Health 3, Flammability 3, Reactivity 1 vigorous or explosive reaction above -70°C with alkyl aluminum chlorides and aromatic hydrocarbons violently exothermic polymerization reaction with aluminum chloride, boron trifluoride, sulfuric acid incompatible or reacts strongly with nitric acid, ethylene imine, ethylenediamine, chlorsulfonic acid, oleum, sodium hydroxide combustion will produce carbon dioxide, carbon monoxide, and hydrogen chloride use carbon dioxide, alcohol foam, or dry chemical for firefighting purposes. 

Note the most interesting examples. In particular, as ZnCh is added, we can observe an accelerated radiation polymerization of allyl acetate and allylamine by 6 and 30 times, respectively. When MX complexes include conventional monomers, the polymerizations are also typical in the case of ZnCl2. The same is observed for C0CI2, NiCU, and PdCE complexes with ethylene and triethylene imines and their derivatives (ML Cl2 witii = 1 to 4). Owing to the formation of a coordinate bond, these complexes are distinguished by a rearrangement of the electronic density at the atoms and bonds of the heterocycle, with the result that the ring stress increases appreciable (e.g. for ethylene imine by 42 kJ mol ) [78]). 

SCLCPs have also been prepared by alkylation and/or quatemization of linear poly (ethylene imine)s [215, 216] and po-ly(4-vinylpyridine)s [217-223] with meso-genic alkyl halides or carboxylic acids. Although these precursor polymers can be prepared by controlled cationic [224] and anionic [225, 226] polymerizations, respectively, living polymerizations were either not used to prepare the SCLCPs, or the mo-... 

Toxicology LD50 (oral, rat) 7070 mg/kg, (skin, rabbit) 10 g/kg low toxicity by ing., skin contact skin irritant TSCA listed Precaution Powerful reducing agent mixts. with air may explode violent polymerization in contact with water violent reactions with chlorosulfonic acid, ethylene imine, NaOH, etc. can explode during mfg. 

A further technically important polymer produced via cationic polymerization is poly (ethylene imine) (PEI). PEI is polymerized from aziridine via protons (Fig. 3.15). It is a highly branched product due to chain growth also through the secondary amines, and it is used, for example, for paper treatment and coatings. More recently, it has also drawn interest for biomedical applications despite its relatively high cytotoxicity [9]. 

Substitution on the ethylene imine ring hinders polymerization. The 2,3- and 1,2-substituted aziridines fail to polymerize. Only low molecular weight linear and cyclic oligomers form from 1-and 2-substituted ethylene imines. 

Some polymers already contain reactive groups that can initiate a graft polymerization. The hydroxyl groups in cellulose initiate the polymerization of ethylene imine ... 

Poly ethylene imines) are polymers with two carbon atoms between each nitrogen atom in the main chain, that is, they are actually secondary amines. Unbranched poly(ethylene imines) are obtained by the isomerization polymerization of unsubstituted 2-oxazolines initiated by C2H5[BF30C2Hs] with subsequent saponification of the products ... 

Branched poly(ethylene imines) are obtained by the cationic polymerization of ethylene imine with protonic acids or alkylating reagents as initiators, i.e.,... 

The cationic polymerization of TV-substituted ethylene imines proceeds similarly. AT-/-butyl ethylene imine is an exception, since its polymerization occurs without termination or transfer, and so, is a living polymerization. 

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