Styrene terpolymerization

Styrene terpolymerization, with sulfur dioxide and methyl methacrylate, 418 Styromal resins, SMA copolymers, 426, 445 2-Styryl-2-methyl-1,3-dioxane, MA copolymerization, 331... 

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. 

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. 

Styrene-1,3-butadiene copolymers with higher styrene contents (50-70%) are used in latex paints. Styrene and 1,3-butadiene terpolymerized with small amounts of an unsaturated carboxylic acid are used to produce latexes that can be crosslinked through the carboxyl groups. These carboxylated SBR products are used as backing material for carpets. Styrene copolymerized with divinyl benzene yields crosslinked products, which find use in size-exclusion chromatography and as ion-exchange resins (Sec. 9-6). 

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

Terpolymerization of J31) and 4-6S2) with styrene and butadiene led to polymers containing both azo groups (which can be used subsequently as radical sources) and C=C double bonds ... 

Table 3.11. Results from the terpolymerization of 4 6 with styrene and butadiene...

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. 

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... 

Several works [311-313, 200] are devoted to a circumstantial research of systems where terpolymerization of styrene and acrylonitrile with a third monomer (brominated acrylate or methacrylate) was studied. It was shown that the terminal model can be employed to describe such systems. One can see this from Table 6.10 and Figs. 20 and 21, where the conversion drifts of the average copolymer composition are presented. 

First let us demonstrate the possibilities of predicting transparency and heat resistance of (styrene + methylacrylate + heptyl acrylate) terpolymerization of the products prepared at complete conversion of monomers. The elements ry of the matrix of reactivity ratios ... 

To predict the glass transition temperature of (styrene + methylacrylate + hep-tyl acrylate) terpolymerization products from Eq. (7.2) one should calculate the fractions of all dyads using reactivity ratios (7.4). Combining such calculations with experimental data on glass transition temperatures of homopolymers and alternating binary copolymers... 

It is worth emphasizing in conclusion of this section that a similar analysis of the dynamic system (8.3), (8.4) could be also carried out for terpolymerization, since by now experimental data are available on the dependence of the copolymerization rate on monomer feed composition for terpolymers of methyl methacrylate and styrene with either diethyl maleate [344], N-vinylpyrrolidone [344], or acrylonitrile [346]. 

CH3)3CO— is an initiator residue]. With copolymerization of free monomers, they should have observed an increasing A/B ratio according to the method used with complex propagation, A/B should remain constant. The authors observed both cases. They concluded that maleic anhydride with a monomeric donor, like styrene, yields a DA complex by a reversible reaction, with an equilibrium constant of 10-1 to 10-2 dm3 mol-1. The initiating radical is formed from the complex, and the copolymerization is in fact a terpolymerization involving the two free monomers and their complex. These authors have applied the same technique in a study of the type of radicals formed in copolymerization of maleic anhydride with vinyl sulphides. Even in this case they provided evidence of the existence of a complex. 

It may be true that many terpolymerizations are well described by these relations, for example the radical copolymerization of styrene, methyl methacrylate and acrylonitrile or vinyl chloride [205, 206] but the uncertainty of the basic assumptions (stationary state, non existence of monomer or active centre complexes, etc.) reduces the meaning of relation (116) to a mere illustration of a complicated copropagation. No way is known to derive the values of the six constants involved independently. Unless they are determined by independent procedures, it is very probable that a good agreement between experiment and the tested relation will be obtained by a suitable choice of these constants. The value of such an agreement should be regarded with caution. 

Benzyl-2,5-cyclohexadiene-1 -carboxylic acid is a new chain transfer agent that was used to modulate the emulsion terpolymerization of styrene, butadiene, and acryhc acid. Its use resulted in 7% less gel formation than in an equivalent terpolymerization lacking this additive. 

Recently, Akashi and coworkers [153, 154] synthesized novel spherical particles on which nano-projections are uniformly distributed over the whole surface like confetti by the one-step dispersion terpolymerization of acrylonitrile, styrene, and the PEO macromonomer 9a in ethanol/water media. The control of nanoparticle morphology by a one-step synthetic procedure is important to self-organization at the polymer chain level, which is a basis for the formation of biological nanoconstructs such as viruses and organelles. 

In the terpolymerization of styrene, methyl methacrylate and acrylonitrile (s/MMA/AN = 50/25/25 mole ratio) in the presence of EASC, the terpolymer composition is approximately 50/36/1 1, independent of the temperature within the range of 10-90°C, whether the reaction is conducted in the dark or under UV radiation (lO). However, the terpolymerization rate is increased 2-5 times under UV light. 

Examples of terpolymerizations have also been reported ethylene/styrene/l,5-hexadiene,561 ethylene/propylene/... 

Table 27 Styrene-ethylene-isoprene terpolymerization catalyzed by complex 94 [196]...

Furthermore, the phosphine-dihydrooxazole hgands show an unusual behavior with respect to ethene and styrene. The productivity of those systems is larger for styrene than for ethene under equal reactions conditions nevertheless, in the terpolymerization experiments ethene, and not styrene, is prevailingly inserted. Considering that ethene was inserted more rapidly than styrene into model acetyl complexes [103], the poisoning" effect of ethene can be explained by assuming that ethene is coordinated more easily, without rapid olefin dissociation, and that rate-determining carbon monoxide insertion into the two different alkyl intermediates occurs. 

Analogous to the case of styrene, the terpolymerization reactions of propene with ethene were carried out to identify the factors responsible for enantioface discrimi-... 

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