New progress in the synthesis of bio based PET polyester by Ningbo Materials Institute

At present, the widely used bio based polymer materials mainly include PLA, PHA, PGA, PBS, etc these polymer materials take renewable resources as the main raw materials to reduce the consumption of petrochemical products in the plastic industry and the environmental pollution in the production process of petroleum based raw materials It has the dual effects of saving oil resources and protecting the environment It is an important development direction of polymer materials at present, and also one of the important means to realize "energy conservation and emission reduction", develop "green economy" and "low carbon economy" However, in practical application, the mechanical properties (such as strength, modulus, creep resistance, etc.) and heat resistance (such as thermal mechanical properties, thermal deformation temperature, etc.) of these bio based polymer materials are significantly lower than those of petroleum based engineering plastics such as polyethylene terephthalate (PET), polycarbonate (PC), aromatic nylon (PA), bisphenol A-type epoxy resin (epoxy), so they can not be fully filled There is a great demand for polymer materials based on podophylls in the field of engineering plastics The basic reason is the lack of rigid aromatic ring structure in the molecular skeleton of bio based polymer materials, which leads to the low performance Therefore, in order to partially replace and supplement petroleum based polymers, it is urgent to introduce rigid ring structure into their molecular structure through synthesis technology to endow them with higher heat resistance and mechanical properties, so as to realize the application of biological based polymers in the field of engineering plastics and effective replacement of petroleum based polymers The team of bio based polymer materials led by Zhu Jin, researcher of Ningbo Institute of materials, Chinese Academy of Sciences, through copolymerization of 2,5-furandioic acid and glycol, prepared a series of bioaromatic polyester PEF (also known as bio based PET) with different furan ring content in the molecular structure by direct esterification polycondensation, as shown in figure 1, with the intrinsic viscosity controlled between 0.75-0.98dl/g TGA and DSC showed that TG of bio based polyester increased significantly, Tg of PEF increased by 18 ° C, melting temperature decreased by 40 ° C, and strength and modulus increased significantly The material gas barrier test shows that the CO2 barrier property of PEF is 14.8 times higher than that of pet, and the O2 barrier property is 6 times higher than that of pet Due to the good heat resistance, strength, modulus and barrier property of the bio based aromatic polyester PEF, the current scale-up to 5L reactor has realized the PEF kilogram level preparation, the intrinsic viscosity is between 0.65-0.95dl/g, the different levels are accurately controlled, and the problem of the color yellowing of the furan polyester has been solved, and a colorless transparent copolyester has been prepared On this basis, the application research of fiber, film, engineering plastics and other fields is carried out, as shown in Figure 2 At present, it has applied for 9 related Chinese and international patents (cn201410763313.2, cn201410787166.2, PCT / cn2014 / 09406620161083122652016108312138, etc.) In order to expand the application field of PEF, a high toughness furan copolyester PECF has been developed, which has excellent comprehensive performance The Tg of PECF is 11 ° C higher than that of pet, the melting temperature is 35 ° C lower, the CO2 barrier performance is 5.2 times higher than that of pet, the O2 barrier performance is 3.2 times higher than that of pet, and the elongation at break reaches 154% The performance comparison is shown in Table 1 and figure 3, which fully meets the manufacturing demand of plastic beer bottle The developed high temperature resistant furan copolyester PETF series polyester has the highest glass transition temperature of 122 ° C and good impact performance Compared with polycarbonate (PC), it overcomes the disadvantage of poor solvent resistance of PC PETF series bio based aromatic polyester has high temperature resistance, solvent resistance, good impact resistance and human contact safety It is very suitable for manufacturing baby bottles, toys, etc it can also replace and supplement PC for many fields such as aviation, automobile manufacturing, etc (polymer, 2016, 103:1-8.) Fig 1 Application of furan dicarboxylic polyester Fig 1 performance comparison between PECF and pet Fig 2 PECF