Study On The Synthesis And Properties Of Acid-dyestuff Dyeable Polyester

In this thesis a series of copolyesters were synthesized by direct-esterification and polycondensation with the addition of XIPA,XTPA,PEG and their fibers have been spinned.The properties of the modified polyesters were studied.The fibers have been dyed with acidic dyestuff in atmosphere and water-boiling temperature.The dyeability was compared with wool,silk,PA6,and normal PET.The esterification kinetics of copolyester with the addition of XIPA has been investigatied.Furthermore,the 4a#modified polyester was synthesized by scale-up experiment in 301 reactor and then spinned with normal experimental extruder.The properties and dyeability of 4a#modified polyester had been analized in the same methods.The results showed that with the addition of third monomer the melting temperature(Tm)and the glassy transition temperature(Tg)of the modified copolyesters decreased.The addition of XIPA resulted in the increase of cold crystallization temperature(Tcc),while the XTPA had no effect on Tcc.The thermal weight loss of copolyesters was about the same as common PET.The grain size of modified polyesters was bigger than common PET.The acid dyeing results showed that the dyeability of copolyester fibers containing the XIPA is better than the fibers containing XTPA.After systematical experiments a better results had been abtained:under the condition of dyeing at atmosphere and boiling temperature for 1h,bath ratio 1:50,dyestuff content 2%(owf),the dye uptake of 4#could reach 72.7%for the Weak Acid Brilliant Green 3GM 49.1%for Oprah winfrey red B.The self-made modified copolyester fibers were much better than common PET fiber,but could not match wool,silk and PA6 yet.The scale up experiment of modified polyester was according to 4#,the product 4#-large was obtained and then spinned with extuder.The dye uptake of 4#-large fiber was up to 86.8%when dyed in the same condition(the dyestuff is Oprah winfrey red B)as above.This might be because the more fine denier.The Dye and fiber contact area is more conducive to dyeing.