Synthesis And Application Of Polymaleic Acid Dyes And Hydroxymethyl Polymeric Dyes

In this thesis, polymaleic acid dyes and hydroxymethyl polymeric dyes for cotton fiber were designed and synthesized. As polymeric dyes contain multiple reactive groups, high fixation could be achieved through covalent bonds between polymeric dyes and cotton after dyeing and fixation.CY1-NO2, CY2-NO2 and CY3-NO2 were synthesized by diazotization and coupling reaction by using p-nitroaniline as diazo component, and p-cresol,3-aminoformyl-l-ethyl-6-hydroxy-4-methyl-2-pyridone, and 1-(2’,5’-dichloro-4’-sulfo-phenyl)-3-methyl-5-pyrazolone as coupling compounds. CY1-NH2, CY2-NH2 and CY3-NH2 were prepared by reduction of CY1-NO2, CY2-NO2 and CY3-NO2 with sodium sulfide in ethanol/water, toluene/water and water, respectively. And their structures were characterized by IR,1H NMR and API-ES mass spectroscopy.Polymaleic anhydride (PMA) was prepared in toluene initiated with benzoyl peroxide (BPO). Three polymaleic acid dyes with grafting ratio of 30% were synthesized by the reaction of PMA with CY1-NH2, CY2-NH2 and CY3-NH2, respectively. Amide was formed when ammonia reacted with PMA and imide was formed if urea was used. It proved that, amide or imide could be formed when using different agents under different reaction conditions. Based on this method, polymeric dyes with amide and imide groups were prepared derived from PMA-DY1, PMA-DY2 and PMA-DY3 synthesized in this thesis and PMA-DY4 and PMA-DY5 prepared by our research team, then the reaction with HCHO was carried out to prepare hydroxymethyl polymeric dyes. The structures of polymeric dyes were characterized by IR and 1H NMR.Poly(maleic anhydride-acrylamide) (MA-AAm) was synthesized in tetrahydrofuran with azodiisobutyronitrile as free radical initiator. The structures of MA-AAm were characterized by FT-IR and GPC. In order to solve the problems of declining of utilization ratio of MA and of the yield of MA-AAm with the increase of dosage of MA, a technique for recycling use of polymerization residue was designed. The utilization ratio of MA and the yield of the copolymer were enhanced, and the content of MA within the copolymer did not change much. CY4-NH2 (4-((4’-aminophenyl)-azo)-1-phenyl-3-methyl-5-pyrazolone) was used to react with the copolymer of MA-AAm. The grafting ratio of CY4-NH2 was only 11.4%.The solubility and the stability at different pH of two kinds of polymeric dyes were studied. It showed that, all polymeric dyes had good water-solubility when pH was above 7. DY1, DY2 and DY4 not containing water-soluble groups could dissolve in polar organic solvents. Aqueous solution of polymaleic acid dyes and hydroxymethyl polymeric dyes possessed good stability when pH was 3-10 at room temperature. Covalent bonds between polymeric dyes and cotton fibers were investigated by color stripping. Dip-pad dyeing method was used for all the dyes synthesized. The colorfastness on cotton and tear strength of the dyed cotton fibers were measured. The results showed that these polymeric dyes were suitable for dyeing cotton fibers. Formaldehyde released from the cotton fibers dyed with hydroxymethyl polymeric dyes was less than 75 mg/kg, it conformed to the requirements of national standard GB 18401-2003 (National general safety technical code for textiles products).