Terpolymerization monomer

Terpolymerizations or ternary copolymerizations, as the names suggest, are polymerizations involving three monomers. Most industrial copolymerizations involve three or more monomers. The statistics of terpolymerization were worked out by Alfrey and Goldfinger in 1944.111 If we assume terminal model kinetics, ternary copolymerization involves nine distinct propagation reactions (Scheme 7.9). 

Azeotropic compositions are rare for terpolymerization and Ham 14 has shown that it follows from the simplified eqs. 38-40 that ternary azeotropes should not exist. Nonetheless, a few systems for which a ternary azeotrope exists have now been described (this is perhaps a proof of the limitations of the simplified equations) and equations for predicting whether an azeotropic composition will exist for copolymerizations of three or more monomers have been formulated.20113 This work also shows that a ternary azeotrope can, in principle, exist even in circumstances where there is no azeotropic composition for any of the three possible binary copolymerizations of tire monomers involved. 

The overall composition at low conversion of binary copolymers formed in the presence of a chain transfer agent can be predicted analytically using an expression analogous to that used to describe terpolymerization where one monomer does not undergo propagation (Section 7.3.2.4),2j6 Making the appropriate substitutions, eq. 37 becomes eq. 70 ... 

A Japanese patent72) claims the synthesis of thermally stable copolymers by free-radical terpolymerization of dialkylstannyl dimethacrylates, glycidyl methacrylate and vinyl monomers (vinyl chloride, styrene, vinyl acetate, etc.). The products contain 0.5 to 30% tin and 0.05 to 7 % epoxide oxygen. 

Some characteristics of free-radical terpolymerization of tri-butylstannyl methacrylate, styrene and maleic anhydride governed by the pentacoordination state of the tin atom are reported in Refs. 95),96). It is shown that a coordination-bound monomer has a considerable effect on chain initiation and propagation. Copolymerization mainly involves the participation of complex-bound monomers. 

A microgel of a dz = 76 nm which is suitable for coupling with proteins, can be prepared by emulsion terpolymerization of NjAT -tetramethylene bisacrylamide, n-hexylmethacrylamide and propene acid amide-N-(4-methyl-2-butyl-1,3-diox-olane) [291 ]. The diameter of these microgels may be varied by the concentration of the emulsifier (Fig. 57) and is rather uniform. As the CMC of this system is about 2.5 X10"3 mol SDS/1, it may be assumed that below this value the copolymerization essentially takes place in the monomer droplets, whereas at higher concentrations of SDS preferentially the monomers in micelles are polymerized. 

The two monomers enter into the copolymer in overall amounts determined by their relative concentrations and reactivities. The simultaneous chain polymerization of different monomers can also be carried out with mixtures of three or more monomers. Such polymerizations are generally referred to as multicomponent copolymerizations the term terpolymerization is specifically used for systems of three monomers. 

Terpolymerization, the simultaneous polymerization of three monomers, has become increasingly important from the commercial viewpoint. The improvements that are obtained by copolymerizing styrene with acrylonitrile or butadiene have been mentioned previously. The radical terpolymerization of styrene with acrylonitrile and butadiene increases even further the degree of variation in properties that can be built into the final product. Many other commercial uses of terpolymerization exist. In most of these the terpolymer has two of the monomers present in major amounts to obtain the gross properties desired, with the third monomer in a minor amount for modification of a special property. Thus the ethylene-propylene elastomers are terpolymerized with minor amounts of a diene in order to allow the product to be subsquently crosslinked. 

The terpolymerization and multicomponent composition equations are generally valid only when all the monomer reactivity ratios have finite values. When one or more of the... 

In copolymerizations of three monomers there are nine growing steps to be taken into account. From these, six reactivity ratios can be derived. They are difficult to obtain from terpolymerizations and are therefore taken from binary copolymerizations. 

Seeded Emulsion Terpolymerization of Vinyl Acetate, Butyl Acrylate, and Vinyl Neodecanoate with Gradual Monomer and Initiator Additions... 

Terpolymerization of Some Azo Monomers 3.2.4.1 Terpolymerization with Butadiene and Styrene... 

A retarding effect of monomers similar to 3 on the overall rate of the polymerization and on the molecular masses of the products was explained by evoking the reaction of the azo compounds with the chain propagating radicals to yield the stabilized hydrazyl radicals. The results of the terpolymerization with 4-6 are given in Table 3.11 52). 

Terpolymerization of MM A and 1,2-Butanediol Dimethacrylate with l, 3 and 6 The terpolymerization of MMA and 1,4-butanediol Dimethacrylate (BDDM) with azo monomers leads to networks with labile, azo groups as network bridges 50,51 These polymerizations were carried out in emulsion using dimyristile peroxydicarbon-ate as the initiator (see Table 3.12). 

Further evidence for the participation of the charge transfer complex in these terpolymerization systems was obtained by dilution experiments (12). The effect of dilution with various solvents on the AN content of the terpolymer is shown in Figure 4. Except for chloroform, the AN content of the copolymer increases with dilution. This suggests a higher order dependence of monomer consumption on monomer concentration... 

The range of polymerizable combinations was found to be even wider if a third monomer such as AN was added. For some weaker-D/weaker-A pairs such as VN/DEF, terpolymerization actually occurred in AN as solvent. So it is proposed that in these systems initiating radicals were formed which then were trapped by the very active monomer AN, resulting in chain propagation. 

One way to achieve this result relies on the change in the relative monomer reactivity following composition drifts. Thus, in a combination ofhigh and low reactivity monomers, the former will preferentially react first, leaving a considerable proportion of the latter for copolymerization when the supply of the high reactive monomer is depleted. This has been confirmed in the terpolymerization of methyl methacrylate/butyl acrylate/vinyl acetate in the presence of the maleate Surfmer reported in Figure 6.49. 

The scope of the spontaneous copolymerization of P(III) monomers has been extended to copolymerizations with more sophisticated regulations of the arrangements of monomeric units in copolymers. They include a 2 1 sequence-ordered binary copolymerization of 43 with 46 (Eq. (27))30) and 1 1 1 sequence-ordered terpolymerizations of 54/acrylate 47jCQ2 (Eq. (28)) 39) and 48/49139 (Eq. (29))40 ... 

In the terpolymerization of styrene, 2-ethylhexyl acrylate, and glycidyl acrylate a continuous-addition type of technique was used, and attempts were made to achieve maximum conversions. Relationships were sought between molecular weights, molecular weight distributions, reaction temperature, initiator concentration, half-life of the initiator, and rate of monomer-initiator addition. The molecular weights of the products depended strongly upon reaction temperature and on the rate of initiator decomposition. Narrower molecular weight distributions resulted from the use of initiators with shorter half-lives. 

The terpolymerizations described were carried out by a continuous feed method, unless stated otherwise, where both the monomer mixture and the initiator were added together continuously to the reaction kettle (18). The variables studied were (1) effects of initiators with different half-lives, (2) effects of variations in temperature, and (3) effects of variations in concentrations of initiators. Attempts were also made to study the extent of heterogeneity in the products. 

When both monomer and initiator are added simultaneously, the rate of monomer and initiator addition to the reaction doesn t appear to be very critical. This was shown in a study of homopolymerization of styrene (19) and appears to be true in this terpolymerization (Table IX). Variations in Mw/Mn appear small. However, there is a decrease in Mw... 

Analysis of data obtained from reactions with mixtures of purified monomers (18) permitted calculations of Kp2/Kt and kinetic chain lengths for these terpolymerization reactions using the following two relationships (6,9) ... 

Iwatsuki and Yamashita (46, 48, 50, 52) have provided evidence for the participation of a charge transfer complex in the formation of alternating copolymers from the free radical copolymerization of p-dioxene or vinyl ethers with maleic anhydride. Terpolymerization of the monomer pairs which form alternating copolymers with a third monomer which had little interaction with either monomer of the pair, indicated that the polymerization was actually a copolymerization of the third monomer with the complex (45, 47, 51, 52). Similarly, copolymerization kinetics have been found to be applicable to the free radical polymerization of ternary mixtures of sulfur dioxide, an electron donor monomer, and an electron acceptor monomer (25, 44, 61, 88), as well as sulfur dioxide and two electron donor monomers (42, 80). 

The diradical nature of the intermediate in the copolymerization of monomers through a charge transfer intermediate has been suggested by Zutty et al. (88) as a result of studies on the copolymerization and terpolymerization of monomer systems containing bicycloheptene and sulfur dioxide. The third monomer apparently enters the copolymer chain as a block segment, while the donor-acceptor monomer pair enter the chain in a 1 1 molar ratio, irrespective of the ratio present in the monomer mixture. 

Similar results have been noted in terpolymerizations involving the p-dioxene-maleic anhydride (49, 51, 52) and vinyl ether-maleic anhydride (45, 49) and vinyl ether-fumaronitrile (49) monomer pairs. Iwatsuki and Yamashita (46) concluded that the molecular complex formed between p-dioxene and maleic anhydride is attacked on the p-dioxene side by a radical to yield the maleic anhydride radical which is considered to be the main growing radical. Thus, a monoradical propagation step is considered operative. 

A Flame Resistant ABS-Type Polymer from Terpolymerization with a Novel Bromine-Containing Monomer... 

Even in the first publications concerning the copolymerization theory [11, 12] their authors noticed a certain similarity between the processes of copolymerization and distillation of binary liquid mixtures since both of them are described by the same Lord Rayleigh s equations. The origin of the term azeotropic copolymerization comes just from this similarity, when the copolymer composition coincides with monomer feed composition and does not drift with conversion. Many years later the formal similarity in the mathematical description of copolymerization and distillation processes was used again in [13], the authors of which, for the first time, classified the processes of terpolymerization from the viewpoint of their dynamics. The principles on which such a classification for any monomer number m is based are presented in Sect. 5, where there is also demonstrated how these principles can be used for the copolymerization when m = 3 and m = 4. 

The parameters a = l/rij5 the number of which equals m(m — IX are reciprocal reactivity ratios (2.8) of binary copolymers. Markov chain theory allows one, without any trouble, to calculate at any m, all the necessary statistical characteristics of the copolymers, which are formed at given composition x of the monomer feed mixture. For instance, the instantaneous composition of the multicomponent copolymer is still determined by means of formulae (3.7) and (3.8), the sums which now contain m items. In the general case the problems of the calculation of the instantaneous values of sequence distribution and composition distribution of the Markov multicomponent copolymers were also solved [53, 6]. The availability of the simple algebraic expressions puts in question the expediency of the application of the Monte-Carlo method, which was used in the case of terpolymerization [85,99-103], for the calculations of the above statistical characteristics. Actually, the probability of any sequence MjMjWk. .. Mrl 4s of consecutive monomer units, selected randomly from a polymer chain is calculated by means of the elementary formula ... 

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