Copolymers vinylic monomers

Acrilan A brand name for a synthetic fibre, based on a copolymer of acrylonitrile with minor proportions of other unspecified vinyl monomers. See also propenenitrile. 

Radicals are employed widely in the polymer industry, where their chain-propagating behavior transforms vinyl monomers into polymers and copolymers. The mechanism of addition polymeri2ation involves all three types of reactions discussed above, ie, initiation, propagation by addition to carbon—carbon double bonds, and termination ... 

Vinyl acetate is another monomer used in latex manufacture for architectural coatings. When copolymerized with butyl acrylate, it provides a good balance of cost and performance. The interior flat latex paint market in North America is almost completely dominated by vinyl acetate—acryHc copolymers. Vinyl acetate copolymers are typicaHy more hydrophilic than aH-acryHc polymers and do not have the same ultraviolet light resistance as acryHcs as a result. 

Vinyl-2-PyrroHdinone. l-Vinyl-2-pyrroHdinone (VP) (l-ethenyl-2-pyrroHdinone, A/-vinyl-2-pyrroHdone, and V-Pyrol) is manufactured by ISP in the United States and by BASF in Germany by vinylation of 2-pyrroHdinone with acetylene. It forms the basis for a significant specialty polymer and copolymer industry and consumes the primary portion of aH 2-pyrroHdinone manufactured (see Vinyl polymers, n-vinyl monomers and polymers). 

GopolymeriZation. The importance of VDC as a monomer results from its abiHty to copolymerize with other vinyl monomers. Its Rvalue equals 0.22 and its e value equals 0.36. It most easily copolymerizes with acrylates, but it also reacts, more slowly, with other monomers, eg, styrene, that form highly resonance-stabiHzed radicals. Reactivity ratios (r and r, with various monomers are Hsted in Table 2. Many other copolymers have been prepared from monomers for which the reactivity ratios are not known. The commercially important copolymers include those with vinyl chloride (VC),... 

VEs can also copolymerize by free-radical initiation with a variety of comonomers. According to the and rvalues of 0.023 and —1.77 (isobutyl vinyl ether), VEs are expected to form ideal copolymers with monomers of similar and e values or alternating copolymers with monomers such as maleic anhydride (MAN) that have high values of opposite sign (Q = 0.23 e = 2.25). 

Solvent Evaporation from Solutions of Thermoplastic Polymers. A solution of a copolymer of vinyl chloride (chloroethene) [75-01-4] C2H2CI, vinyl acetate (acetic acid ethenyl ester) [108-05-4] and a hydroxy-functional vinyl monomer having a number average molecular... 

A waterborne system for container coatings was developed based on a graft copolymerization of an advanced epoxy resin and an acryHc (52). The acryhc-vinyl monomers are grafted onto preformed epoxy resins in the presence of a free-radical initiator grafting occurs mainly at the methylene group of the aHphatic backbone on the epoxy resin. The polymeric product is a mixture of methacrylic acid—styrene copolymer, soHd epoxy resin, and graft copolymer of the unsaturated monomers onto the epoxy resin backbone. It is dispersible in water upon neutralization with an amine before cure with an amino—formaldehyde resin. 

Vinyl plastics Group of plastics composed of resins derived from vinyl monomers, excluding those that are covered by other classifications (i.e., acrylics and styrene plastics). Examples include PVC, poly(vinyl acetate), poly(vinyl butyral), and various copolymers of vinyl monomers with unsaturated compounds. 

Radical copolymerization is used in the manufacturing of random copolymers of acrylamide with vinyl monomers. Anionic copolymers are obtained by copolymerization of acrylamide with acrylic, methacrylic, maleic, fu-maric, styrenesulfonic, 2-acrylamide-2-methylpro-panesulfonic acids and its salts, etc., as well as by hydrolysis and sulfomethylation of polyacrylamide Cationic copolymers are obtained by copolymerization of acrylamide with jV-dialkylaminoalkyl acrylates and methacrylates, l,2-dimethyl-5-vinylpyridinum sulfate, etc. or by postreactions of polyacrylamide (the Mannich reaction and Hofmann degradation). Nonionic copolymers are obtained by copolymerization of acrylamide with acrylates, methacrylates, styrene derivatives, acrylonitrile, etc. Copolymerization methods are the same as the polymerization of acrylamide. 

The polymers initiated by BP amines were found to contain about one amino end group per molecular chain. It is reasonable to consider that the combination of BP and such polymers will initiate further polymerization of vinyl monomers. We investigated the photopolymerization of MMA with BP-PMMA bearing an anilino end group as the initiation system and found an increase of the molecular weight from GPC and viscometrical measurement [91]. This system can also initiate the photopolymerization of AN to form a block copolymer, which was characterized by GPC, elemental analysis, and IR spectra. The mechanism proposed is as follows ... 

Photoinitiators provide a convenient route for synthesizing vinyl polymers with a variety of different reactive end groups. Under suitable conditions, and in the presence of a vinyl monomer, a block AB or ABA copolymer can be produced which would otherwise be difficult or impossible to produce by another polymerization method. Moreover, synthesis of block copolymers by this route is much more versatile than those based on anionic polymerization, since a wider range of a monomers can be incorporated into the blocks. 

If (P ) is terminated by a chain transfer to a solvent or a monomer, a graft copolymer is formed, or, if the termination is from a combination, a crosslinked network polymer is formed. If the pre-existing polymer (B) contains an end group that itself is photosensitive (or can produce a radical by interacting with photoinitiator) and in the presence of a vinyl monomer (A), block copolymer of type AB can be produced if the photosensitive group is on one end of the polymeric chain. Type ABA block copolymer can be produced if the polymer chain (B) contains a photosensitive group on both ends. 

Using the same method a block copolymer of polypeptides and vinyl monomers was also prepared. As mentioned in Section II, Bamford and Mullik [22] introduced an interesting method of photoinitiation of vinyl monomers by the Mn2(CO)io or the Re2(CO)io/C2F4 system. By these methods polymeric molecule with (CO)sMn—CF2CF2—terminals is produced (see Scheme [12]). If a polymer of this kind is heated to 100°C in the presence of vinyl monomer, a block copolymer AB or ABA with Cp2- F2 linkage is produced [ ] ... 

Bamford and Mullik [62] have succeeded in photografting a vinyl monomer onto a styrene-MMA copolymer using the Mn2(CO)io/C2F4 photoinitiating system in acetic acid. The following scheme was reported for this process ... 

It was found that the sulfate radical anion S04 produced photochemically in Scheme (46) is responsible for generating the cellulose derivative macroradicals by hydrogen abstraction, which added the vinyl monomer to produce the grafted copolymer. The main disadvantage of this method is the production of large quantities of undesirable homopolymers in addition to the grafted copolymers. 

Cardanol grafted cellulose. One of the advanced techniques to improve the properties of a polymer is to graft another polymer onto it. Grafting of vinyl monomers onto cellulose has been the subject of extensive studies during the last decade or two. Grafted cellulose copolymers have been found to have improved proper-... 

If polyvinyl alcohol is used as the reducing agent and the oxidation is conducted in the presence of vinyl monomer, grafting occurs. This method of grafting yields substantially pure graft copolymers since the free radicals are formed exclusively on the polymer backbone. 

The reaction of any one of these two radicals with vinyl monomer leads to the formation of a grafted copolymer. 

If a vinyl monomer is polymerized in the presence of cellulose by a free radical process, a hydrogen atom may be abstracted from the cellulose by a growing chain radical (chain transfer) or by a radical formed by the polymerization catalyst (initiator). This leaves an unshared electron on the cellulose chain that is capable of initiating grafting. As cellulose is a very poor transfer agent [10], very little copolymer results from the abstraction of hydrogen atoms by a growing chain radical. The... 

Polymerization of styrene or methyl methacrylate by macroazoinimers having two vinyl groups (MIM-2v) resulted in crosslinked block copolymers, while macroazoinimers with one vinyl end (MIM-1 v) group to polymerize vinyl monomers yielded branched block copolymers. 

Homopolymerization of macroazoinimers and co-polymerization of macroinimers with a vinyl monomer yield crosslinked polyethyleneglycol or polyethyleneglycol-vinyl polymer-crosslinked block copolymer, respectively. The homopolymers and block copolymers having PEG units with molecular weights of 1000 and 1500 still showed crystallinity of the PEG units in the network structure [48] and the second heating thermograms of polymers having PEG-1000 and PEG-1500 units showed that the recrystallization rates were very fast (Fig. 3). 

Depending on the termination reaction of the vinyl monomer, termination by disproportionation or termination by combination occurs. As a result, AB or ABA block copolymers might be obtained. 

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