Allyl esters polymerization

This ratio may also be estimated from a deteimination of the amount of initiator residues found in the monomer. From such data the significance of degradative chain-transfer in an allyl ester polymerization can be judged. For example, it was found that in the allyl ethyl carbonate polymerization, degradative chain-transfer predominates, whereas in the polymerization of allyl laurate and allyl benzoate, effective chain-transfer predominates [19]. 

The polymerization of acrylic and vinyl esters generally proceeds quite rapidly, with relatively low levels of initiators, to form products of considerable molecular weight. By contrast, allyl esters polymerize slowly with high levels of... 

Transfer to monomer is of particular importance during the polymerization of allyl esters (113, X=()2CR), ethers (113, X=OR), amines (113, X=NR2) and related monomcrs.iw, 8, lb2 The allylic hydrogens of these monomers arc activated towards abstraction by both the double bond and the heteroatom substituent (Scheme 6.31). These groups lend stability to the radical formed (114) and are responsible for this radical adding monomer only slowly. This, in turn, increases the likelihood of side reactions (i.e. degradative chain transfer) and causes the allyl monomers to retard polymerization. 

In the 1952 paper mentioned above [3], Gilman reported on the formation of lithium dimethylcuprate from polymeric methylcopper and methyllithium. These so-called Gilman cuprates were later used for substitution reactions on both saturated [6] and unsaturated [7, 8, 9] substrates. The first example of a cuprate substitution on an allylic acetate (allylic ester) was reported in 1969 [8], while Schlosser reported the corresponding copper-catalyzed reaction between an allylic acetate and a Grignard reagent (Eq. 2) a few years later [10]. 

The subject of graft polymerization is usually regarded as beginning with the work of Carlin, and Shakespeare (1) in 1946. However, it is interesting to note that already in 1943 Ushakov (2) reported on the synthesis of vinyl and allyl esters of cellulose which he used for subsequent copolymerization experiments with maleic esters. It seems safe... 

Cyano compounds liquid crystals, 12, 278 in silver(III) complexes, 2, 241 Cyanocuprates, with copper, 2, 186 Cyano derivatives, a-arylation, 1, 361 Cyanosilanes, applications, 9, 322 Cyclic acetals, and Grignard reagent reactivity, 9, 53 Cyclic alkenes, asymmetric hydrosilylation, 10, 830 Cyclic alkynes, strained, with platinum, 8, 644 Cyclic allyl boronates, preparation, 9, 196 Cyclic allylic esters, alkylation, 11, 91 Cyclic amides, ring-opening polymerization, via lanthanide catalysis, 4, 145... 

Monomers that copolymerize with thiocarbonyl fluoride include olefins, vinyl halides, vinyl esters, allyl esters, acrylates, vinyl ethers, and vinyltrichloro-silane. Nonconjugated diolefins lead to crosslinked products. Conjugated dienes inhibit polymerization. 

CHLOROFORMIC ACH> ALLYL ESTER (2937-50-0) Forms explosive mixture with air (flash point 88°F/31°C). Decomposes in water, forming chloroformic acid and allyl alcohol. Incompatible with acids, caustics, amines. Oxidizers, peroxides, elevated temperatures may cause explosive polymerization. Increases the explosive sensitivity of nitromethane. Corrodes metals. 

The polymerization of allyl esters of saturated monobasic acids, e.g., allyl acetate and allyl laurate, yields linear thermoplastic polymers containing 5-20 monomer units per molecule. These homopolymers and copolymers with vinyl monomers such as vinyl acetate, vinyl chloride, and vinylidene cliloride have been used as thermoplastic adhesives and plasticizers. 

The oldest paper we know dealing with the polymerization of a molecule nowadays named as a sur ner is the work of Bistline et al. [4]. They obtained sur ce active polymers with a mean degree of polymerization of about 10 by polymerization erf allylic esters erf sexlium salts of a-sulfe>-stearinic acid and 0E-sulfe)-paImitinic acid. 

Polymerization of Allyl Esters of Higher Monocaiboxylic Acids. 301... 

Polymerization of Allyl Esters of Other Polyftinctional Acids. 322... 

The free-radical polymerization process with allyl esters resembles that of vinyl and acrylic esters in that there are similar initiation, propagation, and... 

The free-radical polymerization of allyl esters exhibits several unique characteristics. In this respect they differ materially from the polymerization characteristics of vinyl esters. 

The kinetic chain length of a free-radical polymerization process is the ratio of kp/kr, where kp is the rate of propagation and ky is the rate of termination. Since allylic hydrogens are not involved in the propagation step, substitution of deuterium for these hydrogens was expected to affect the termination process. When this indeed was found to be the case, as evinced by the increase in the kinetic chain length and the MW of the polymer, it was considered reasonable evidence that the allylic hydrogens were the cause of the characteristic behavior of allyl esters [15]. 

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