Soluble Copolymers of Diallyl Monomers
| Autor: | W. H. Schuller, J. A. Price, W. M. Thomas, S. T. Moore |
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| Rok vydání: | 1959 |
| Předmět: | |
| Zdroj: | Journal of Chemical & Engineering Data. 4:273-276 |
| ISSN: | 1520-5134 0021-9568 |
| DOI: | 10.1021/je60003a021 |
| Popis: | Copolymers containing amino groups are useful in diverse fields such as ion exchange, flocculation, paper stock treatment, and synthetic fibers. While investigating methods for producing such polymers, the authors found that certain diallyl compounds gave soluble copolymers rather than the anticipated gels. This article discusses the relationship of monomer structure to polymer properties, confirming and extending the preceding publications by Butler and others (2-7, 9, 70). Some applications of soluble copolymers are described. When diallyldimethylammonium chloride was copolymerized with acrylonitrile or with acrylamide, the copolymer contained substantial amounts of quaternary compound, yet dissolved in a suitable liquid with no trace of gel. Table I provides examples of this behavior, listing a series of acrylamide copolymers prepared by redox polymerization in water. Solution viscosities were high, indicating molecular weight of the order of one million. Analysis of the copolymers showed that substantial amounts of quaternary compound had been incorporated but without appearance of pendant double bonds. Some of these copolymers were tested as strengthening agents for paper. Paper fibers in aqueous suspensions develop a negative charge; hence, cationic materials, particularly polycationic polymers, tend to be irreversibly adsorbed at the fiber surface. Nonionic or anionic polymers are not adsorbed to the same extent unless mordants such as alum are used. Paper is made from very dilute slurries (0.1 to 0.6y0 on paper machines, 0.0357, on laboratory equipment), so the adsorption mechanism must be efficient for economic utilization of chemical additives to the fiber slurry. These copolymers do improve the strength of paper substantially (Table 11). Other results not listed show that the polymers are effective over a wide p H range. Table I1 also shows that the products are true copolymers. Paper stock slurries were treated with a solution containing 10% polyacrylamide and 27 , monomeric diallyldimethylammonium chloride. Physical properties of the haiidsheets were not improved, indicating that polymer must contain chemically bonded cationic groups to be effective. Copolymers of the same allyl monomer with acrylonitrile are listed at the top of Table 111. Nitrogen analyses showed that the copolymers contained about one half as much allyl compound as was present in the monomer charge. The presence of basic sites was confirmed by a dye adsorption test. Copolymers were of fairly high molecular weight (roughly 100,000 to 300,000 range), but were soluble in dimethylformamide and in aqueous sodium thiocyanate. The 87-13 copolymer was spun successfully into fibers. In this instance an approximately 107, polymer solution in 50% sodium thiocyanate was extruded through a spinnerette into water at a b o g 0" C. The fiber was washed, stretched, and dried. It had typical properties for an acrylic fiber. Experiments with other allyl compounds, also listed in Table 111, show that the ability to form high molecular weight, soluble copolymers is a general property of diallyl compounds of this class. O n the other hand, if three or four allyl groups were attached to nitrogen, the products gave gels in dimethylformamide and were presumably cross-linked. A sulfur compound also gave a soluble copolymer. N,N-Diallylmelamine is a monomer that can lead to soluble or to insoluble copolymers depending on the reaction condi |
| Databáze: | OpenAIRE |
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