Olefinic monomers, functionalizing

Polymerization of Olefinic Monomers Functionalized with Cationic Cyclopentadienyliron Arene Complexes... 

Most ruthenium-initiated ROMP studies have been performed using (233) and strained cyclo-olefinic monomers such as norbornene688 and cyclobutenes,689 although several reports on the polymerization of 8-membered rings have also appeared.690-692 A wide range of functionalities are tolerated, including ethers, esters, amines, amides, alcohols, carboxylic acids, and ketones. 

There are two principal ways to synthesize functional fluoropolymers (a) polymerization of functional fluoromonomers or copolymerization of fluoro-olefins with functional monomers, and (b) modification of common... 

So far, theoretically, there have been two possible approaches for the synthesis of functional polyolefins, namely, (a) direct copolymerization of olefins with functional monomers using polymerization and catalyst technologies, and (b) post-polymerization reaction with polyolefins. 

The first approach has found limited applications. Concerning the direct copolymerization of olefins with functional monomers, studies of copolymerization of olefins by metallocene catalysts have been reported with functional... 

The concept of PO macroinitiators centers on the introduction of an initiation moiety into an olefinic polymer chain for polymerization. The most effective route for preparing PO macroinitiators is by employing functional polyolefins containing hydroxyl groups or other reactive groups. These functional POs are prepared by copolymerization of olefins with functional monomers and post-polymerization reaction, as mentioned above. In the case where an initiation moiety was at the chain-end of the polyolefins, a block type copolymer is produced. It has been reported that thiol-terminated PP was used as polymeric chain transfer agent in styrene and styrene/acrylonitrile polymerization to form polypropylene-b/odc-polystyrene (PP-b-PS) and polypropylene-btock-poly(styrene-co-acrylonitrile) (PP-b-SAN) block copolymer [19]. On the other hand, polymer hybrids with block and graft structures can be produced if initiation moieties are in the polymer chain. 

Controlled radical polymerization (CRP) is an attractive tool, because of the resultant controllability of polymerization, and because of it being a versatile method to synthesize of well-defined polymer hybrids. The three main radical polymerization techniques, ATRP, NMP, and RAFT polymerization, have thus been employed. Other techniques, such as the oxidation of borane groups, have also been studied. In general, using CRP techniques, block copolymers can be synthesized from terminally functionalized PO as PO macroinitiator, and block copolymers can be prepared from functionalized PO produced by the copolymerization of olefins with functional monomers. 

To synthesize graft copolymers by ATRP, the initiation site for living radical polymerization can be incorporated into the polymer chain. In general, copolymerization of olefins with functional monomers can be adopted for syntheses of PO macroinitiators. 

Co(acac)3 is frequently used as a probe for enantioseparation efficiency of col-umns " . A monolytic capillary silica gel column was functionalized with methacrylate residues in two steps, as shown in equation and then it was impregnated with cellulose or amylose (51a, b) which was modified so that 30% of the R groups were the methacrylate group 52 and the rest was identical to R (53). For further stability of the column, the polymeric modifier was immobilized on the silica gel by in situ copolymerization with an olefinic monomer such as 2,3-dimethylbutadiene. Only the column containing cellulose modified as in 51a was able to separate the Co(acac)3 racemic mixture, whereas neither cellulose nor amylose modified as in 51b did, although they were successful in resolving other racemic mixtures ° °. ... 

Copolymerization of olefin monomer(s) with another functionalized monomer e.g., poly(ethylene-co-acrylic acid), poly(ethylene-co-glycidyl methacrylate))... 

Another method for preparing functional Ziegler-Natta polymers is to use an organoborane mediated synthesis. This method has been extensively studied and reviewed by Chung . The success of this technique results from these factors (a) trialkyl boranes are Lewis acids, which are stable to Z-N catalysts, (b) they are soluble in Z-N (hydrocarbon) solvents, (c) they are remarkably versatile synthons for a variety of functional groups. In this case, borane functional alpha olefin monomers (31) are polymerized to polyboranes which can be hydrolyzed to a variety of functional groups. 

The variety of mechanisms by which organotransition metals are able to enchain olefins is reflected in the diverse chemistry discussed above. While much progress has been observed over the past 10-15 years, many challenges remain, including evermore active and selective catalysts, particularly those which are able to handle olefinic monomers with polar functions. 

The main advantage of the use of single-site transition metal alkylidenes in ROMP is the living character, which allows high control over molar mass, leads to narrow dispersity, and offers the chance for block copolymer formation of olefinic, even functional monomers (Fig. 3.24) otherwise not polymerizable by other methods. 

Photoconductive Lithographic Printing Plate Assembly. NVK has been copolymerized with olefinic monomers possessing carboxylic acid, such as acrylic acid, methacrylic acid, fumaric acid, and, maleic anhydride, or carboxylic anhydride [7]. The acid functionality yields copolymers that are soluble in aqueous alkaline media. The copolymers are intended... 

Regarding synthesis of polyolefin nanocomposites with wider applications, copolymerization of ethylene with other olefinic monomers, including higher a-olefins and polar comonomers (with late transition metal catalysts) still needs to be investigated in more detail. For instance, exfohated polyolefin-using chain end functionalized polyolefins can potentially be used as the polymeric surfactants [112]. 

Molecules of a difiinctional monomer such as X-R-Y (where X and Y are mutually reactive functional groups) are polymerized via the elimination of small molecule by-products of XY, a linear condensation polymer with a general formula of X-(-R-)w-Y is formed, whereas when molecules of an olefinic monomer such as H2C=CHR are polymerized, a vinyl polymer with a structure of -[-H2C-CH(R)-]w- is produced. The difunctional and olefinic monomers have been the major monomer sources, and their step and chain polymerization reactions have been the main synthetic routes to the conventional polymers such as polyester and polystyrene, respectively [27]. 

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