Solubility alternating copolymers

Poly(arylene vinylene) derivatives were prepared by Wittig reaction of diphosphonium compounds(I and V), and dialdehyde compounds , Ill,and IV) as shown in Figurel. When I and II, I and IE, I and IV, and V and II are used, soluble alternating copolymers of (A), (B), (C), and (D) are obtained respectively(16,17,18). The diphosphonium compounds were prepared using triphenylphosphine and... 

The condensation product from acrolein and pentaerythritol, 28A, i.e., divinylspirobis-(m-dioxane) or diallylidenepentaerythritol, has been copolymerized with MA under a variety of conditions.At low conversions, using BPO initiator, soluble alternating copolymers are produced. 

In addition to the main product, small quantities (3-5%) of insoluble product are also formed/ Additional work is needed to confirm this structure or determine if the copolymer also contains other ring systems. Attempts have also been made to prepare soluble, alternating copolymers of 4-vinylcyclohexene monoxide and Even though free-radical copoly-... 

PMVEMA, supphed as a white, fluffy powder, is soluble in ketones, esters, pyridine, lactams, and aldehydes, and insoluble in aUphatic, aromatic, or halogenated hydrocarbons, as well as in ethyl ether and nitroparaffins. When the copolymer dissolves in water or alcohols, the anhydride group is cleaved, forming the polymers in free acid form or the half-esters of the corresponding alcohol, respectively. Table 7 illustrates the commercially available alternating copolymers and derivatives. 

Gu Z, Bao Y-J, Zhang Y, Wang M, Shen Q-D (2006) Anionic water-soluble poly(phenyle-nevinylene) alternating copolymer high-efficiency photoluminescence and dual electroluminescence. Macromolecules 39 3125-3131... 

The only product obtained by the copolymerization of styrene and maleic anhydride in acetone was the alternating copolymer even in the presence of more than equimolar quantities of either styrene or maleic anhydride. However, as shown by the data in Table I, larger quantities were obtained than could be accounted for by the formation of the alternating copolymer when excess styrene was used for the copolymerization in benzene solutions. In addition to the precipitates, there was also a trace of benzene-soluble product, which was shown to be polystyrene by infrared spectrometric (28) and pyrolytic gas chromatographic techniques (26). 

Unlike the alternating copolymer, these high yield benzene-insoluble products were not completely soluble in acetone, but they were soluble in a mixture of acetone-benzene (2 1). However, unlike polystyrene, they were precipitated essentially completely when excess benzene was added to the acetone-benzene solutions. In contrast when excess benzene was added to a mixture of polystyrene and the alternating copolymer in an acetone-benzene solution, the copolymer precipitated and the polystyrene remained in the benzene-rich solvent. The polystyrene was recovered from this solution by adding excess methanol. 

Macroradicals obtained by the heterogeneous copolymerization of styrene and maleic anhydride in poor solvents such as benzene were used to initiate further polymerization of selected monomers. This technique was used to produce higher molecular weight alternating copolymers of styrene and maleic anhydride and block copolymers. Evidence for the block copolymers was based op molecular weight increase, solubility, differential thermal analysis, pyrolytic gas chromatography, and infrared spectroscopy. 

Both the mini- and macroemulsion copolymerizations of pMS/MMA tend to follow bulk polymerization kinetics, as described by the integrated copolymer equation. MMA is only slightly more soluble in the aqueous phase, and the reactivity ratios would tend to produce an alternating copolymer. The miniemulsion polymerization showed a slight tendency to form copolymer that is richer in the more water-insoluble monomer. The macroemulsion formed a copolymer that is slightly richer in the methyl methacrylate than the co-... 

Furthermore, in calculations performed manually instead of using software implementing our method, the calculation of the properties of many homopolymers with large repeat units can be simplified by treating them formally as alternating copolymers of smaller repeat units of polymers whose properties have already been calculated. Simple additivity is then assumed to hold for the extensive properties of the alternating copolymer, such as its connectivity indices, cohesive energy, and molar volume. All extensive properties can thus be calculated. Intensive properties, such as the solubility parameter, are defined in terms of extensive properties. Their prediction therefore does not require any detailed calculations either. 

The use of a radical catalyst increases polymerization rate and the extent of grafting. When the reaction is done in an aqueous medium, as when the substrate polymer is charged as a latex, a water-soluble catalyst is necessary, as previously observed for the preparation of alternating copolymers in an aqueous medium (15). Although the latex... 

T t has previously been shown that the rate of the free-radical-initiated copolymerization of maleic anhydride and vinyl monomers is faster in poor solvents than in good solvents, and that the copolymerization rates in these poor solvents decrease as the difference in the solubility parameter values between that of the copolymer and the solvent increases (6, 10). Other investigators have suggested that this free-radical initiation involves hydrogen abstraction, and that the free-radical precursor increases the yield of the alternating copolymer regardless of the monomer charge (3). 

Bailey and co-workers reported that an alternating copolymer of glycine and -aminocaproic acid was degradable by soil microorganisms (7). The corresponding copolymer derived from serine was water soluble and could be degraded more rapidly. 

To synthesize polynucleotide analogues closely resembling natural polymers, we have synthesized several new monomers such as dihydrofuran and dihydropyran derivatives which contained nucleic acid bases (Scheme 1). Copolymerization of the monomers either with maleic anhydride or with vinylene carbonate resulted in the alternating copolymers as shown in Scheme 2. Hydrolysis of the products gave the polymers which were optically active and soluble in water and had alternating sequences along the polymer chain. In this paper we will report synthesis of monomers, their copolymerization either with maleic anhydride or with vinylene carbonate, hydrolysis of the copolymers, and the physicochemical properties of the anhydride and hydrolyzed polymers. 

An alternating copolymer of phenylene vinylene and biarylene vinylene has been described, which has high solubility in an organic solvent and exhibits partial coplanarity to thus realize amorphous properties and superior tt-stacking properties when formed into a film. 

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