Study On Synthesis And Properties Of Water-soluble Copolymers With Fluorinated Alkyl Chains

Water-soluble copolymers with fluorinated alkyl chains show outstanding properties from hydrophobic segments. The water soluble ability of fluorocarbon-modified copolymers can be improved by selected different monomers for copolymerization, as a result, fluorocarbon-modified copolymers with special solution properties will be obtained. And it is an effective method to introduce fluorocarbon chains to the chemical structure of copolymer by designing a novel type monomer with fluorinated alkyl sidechains, and the copolymers with special peoperties can be used for further study. On the basis of the research background and the needs of development, the purpose of this dissertation is focused on the synthesis and characterization of water-soluble copolymers with fluorinated alkyl chains, the study of aggregation behavior of copolymer in aqueous solution and the external application condition of copolymer. The main work and the results of study are as followes:1. A novel fluorocarbon-modified styrene (FS) was synthesized by reacting Fluorinated hexyl ethyl alcohol with4-vinylbenzyl chloride. Amphiphilic fluorocarbon-modified copolymers P(AMPSNa/FS) were synthesized by solution copolymerization of FS with2-acrylamide-2-methylpropanesulfonate sodium. The structures and compositions of copolymers with various contents of Fluorinated alkyl chain segments were confirmed by1H-NMR,19F-NMR, FI-IR and elemental analysis, and the molecular weight of copolymer was detected by means of static laser light scattering. The aggeration behavior of copolymers in aqueous solution was studied by surface tension, electrical conductivity and dynamic laser light scattering as a function of copolymer concentration, test temperature and added salts. The results indicated hat the copolymers were surface-active in aqueous solution and the addition of NaCl promoted the surface tension of copolymer solution reduced. Copolymers show obvious amphiphilic properties in aqueous solution, at low copolymer concentrations t tend to form intramolecular aggregations. And at high polymer concentrations, the intermolecular hydrophobic association is formed. The fluorescence spectroscopy technique without addtionnal probe was employ to measure the solution properties of copolymer as a result of benzene ring introduced into the macromolecular structure, and the test result is consistent with that of other methods. The TEM image indicated the aggregation of copolymer with increasing copolymer concentration, and a simulation diagram was show in this article. The thermogravimetric analysis of copolymer samples shows a satisfactory thermal stability, and it is possess of good application prospect.2. Fluorocarbon-modified diallylamine (DF) was synthesized by reacting diallyl amine with perfluorinatedhexylethyl acrylate. A novel fluorocarbon-modified water-soluble copolymers P(AM/DF) were synthesized by solution copolymerization of acrylamide with various proportions of DF monomers. The structures and composotions of copolymers were confirmed by1H-NMR,19F-NMR, FI-IR and elemental analysis, and the molecular weight of copolymer was detected by means of static laser light scattering. The solution properties of copolymers were researched by surface tension, dynamic laser light scattering and resonance light scattering as a function of copolymer concentration, test temperature, added salts and the contents of hydrophobic fluorocarbon chain segments. The results indicated that the copolymers show a satisfactory surface activity in aqueous solution and the surface tension of solution could be reduced to32mN/m in the measure range. It was found that macromoleculars formed a certain number of intermolecular aggregations in aqueous solution. At low copolymer concentration, the intramolecular aggregation is dominant. The increasing of copolymer concentration promoted the formation of inter-chain aggregation. The addition of salts NaCl leads to the transformation from intramolecular to intermolecular aggregation of copolymer, and the increasing of hydrophobic segments content results in the enhancement of intermolecular association.3. Water-soluble terpolymers with fluorocarbon alkyl chains P(AM/AMPSNa/DF) were synthesized by solution copolymerization of acrylamide,2-acrylamide-2-methylpropanesulfonate sodium with low amounts of DF monomers. The structures and compositions of terpolymers were confirmed by1H-NMR,19F-NMR, FI-IR and elemental analysis, and the molecular weight of terpolymer was characterized by means of static laser light scattering. The aggregation behavior of terpolymers in aqueous solutions was examined by surface tension, dynamic laser light scattering and resonance light scattering methods, as a function of copolymer concentration, added salts and the contents of hydrophobic fluorocarbon chain segments. The results show P(AM/AMPSNa/DF) had a good ability to reduce the surface tension of aqueous solution, and the surface activity increased with the increase of fluorocarbonalkyl chains. The hydrophobic association exist in the terpolymer solutions, and the increasing of terpolymer concentration promote the formation of intermolecular micelles. The influence of added salts to the aggregation behavior of P(AM/AMPSNa/DF) is two-fold, increasing the polar of aqueous solution to promote the inter-chain association and shielding the electrostatic interactions of sulfonic acid. The thermogravimetric analysis indicated the terpolymer showed a satisfactory thermal stability, broadening its application field.