Synthesis And Application Of Modified Polyester With Trace Graphene Oxide

Polyethylene terephthalate(PET)has a wide range of applications in fiber and plastic production,especially in the field of synthetic fibers,accounting for more than 80% of the market.With the rapid development of the national economy today,the national industrial policy and high investment have brought the expansion of polyester production into a peak period,and the polyester industry has ushered in major changes.The demand for independent research and development of polyester continues to increase,and the development of new modified polyesters It seems particularly important.Graphene oxide(GO)contains more oxygen functional groups,less agglomeration and stacking between layers,and has a more stable planar structure.It is widely used in fields such as catalysts,photoelectric displays,and polymer material modification.This research topic is aimed at how to obtain cost-effective modified polyester,aiming to develop a high-strength polyester with high thermal stability and strong crystallinity.Different proportions of GO were used to synthesize modified polyester,the synthesis process of GO/PET polyester was studied and analyzed,the structural properties of modified polyester with different GO content were tested and analyzed,and the spinning experiment was carried out on the modified polyester.The main conclusions are as follows:1.The effect of adding different GO on the PET synthesis process is to promote the synthesis of polyester and make the esterification reaction of PTA and EG more complete.According to the torque at different stages of the polyester synthesis process,it is found that the torque of GO/PET at the same reaction time is greater than that of pure PET,which indicates that the effect of GO on the synthesis process during the polycondensation stage is to increase the viscosity of the polyester.The actual production of modified polyester has reference significance.Through the analysis of intrinsic viscosity and molecular weight test,it is shown that the intrinsic viscosity of GO/PET is between 0.68-0.73 d L/g compared to pure PET when the material is discharged under the same stirring power during the polyester synthesis process,and the relative molecular mass of the viscosity is both in the range.About 20,000 g/mol,it provides a good raw material for polyester chips for subsequent spinning.The test and analysis of the carboxyl end and diethylene glycol content of polyester show that the carboxyl end content of GO/PET is significantly lower than that of pure PET,indicating that the addition of graphene oxide can facilitate the synthesis of PET and make the reaction of modified polyester more complete,The content of diethylene glycol increases with the increase of graphene oxide addition,the spinnability of the sample is enhanced,and the application research is wider.2.The addition of GO can enhance the crystallization and thermal properties of polyester.Through the analysis of the non-isothermal crystallization kinetic parameters of pure PET and GO/PET using XRD,DSC,TG and Avrami equation,it can be found that adding a small amount of GO does not change the basic crystal structure of polyester,but GO acts as a nucleating agent.Compared with pure PET,the number of GO/PET spherulites is significantly increased.The PET macromolecular chains nucleate in different phases with graphene spherulites as the center and are arranged in order to enter the crystal lattice,which greatly increases the crystallization rate of PET,thereby improving the PET's crystallization rate.Crystallization performance.The thermal stability of GO/PET has also been further improved.When the GO content is 30 ppm,the initial decomposition temperature,half-life temperature and residual carbon rate of GO/PET are increased by 9.31?,4.92? and 0.76% respectively compared with pure PET.3.The study on the spinnability of GO/PET found that the addition of trace amounts of GO had little effect on the spinnability of PET chips.During the spinning process,it was found that the polyester chips were evenly ejected and could withstand a larger draft ratio,indicating that GO/ PET chips have excellent spinnability and can be put into actual industrial production.Through the orientation test and analysis,it can be concluded that the greater the draft ratio,the higher the orientation of the fiber;the mechanical property test shows that for the same fiber,the greater the draft ratio,the greater the fiber's breaking strength and the initial The greater the modulus.