Research On Preparation And Properties Of The Biodegradable Materials Films Based On Poly(butylene Adipate-co-terephthalate)

Poly（butylene adipate-co-terephthalate）（PBAT）is a kind of biodegradable polymer material with excellent machinability and good mechanical properties.However,the high price prevents its applications.In order to solute this shortcoming,a common way is blending modification.In this paper,two kinds of blowing film systems were studied:In the blowing film system of PBAT/modified thermoplastic starch（TPS）,the FTIR analysis showed that maleic anhydride（MA）and Titanate coupling agent（TC）reacted with starch,and the modified starch was successfully prepared.The results of dynamic thermomechanical analysis（DMA）and morphology analysis showed that MA could be used as compatibilizer to promote the transesterification of PBAT and TPS.Not only TC can be used as compatibilizer to enhance the compatibility of PBAT and TPS,but can also reduce the aggregation of starch in the film.The mechanical properties test showed that the addition of MA and TC can significantly improve the mechanical properties of the film,the tensile strength of the film in the machine direction and in the transverse direction increased from 13.1/8.3 MPa to 26.7/17.2 MPa,and the modulus of the film also increased from 101.5/84.3 MPa to 155.6/120.7 MPa.According to the contact angle data,MA and TC had little effect on the hydrophobicity of PBAT/TPS films.PBAT/MA-TC-TPS film could be widely used in packaging products and agricultural film fields.According to the degradation experiments,both MA and TC could reduce the degradation rate of PBAT/TPS film,in other words,they could improve the aging resistance of the film.In the blowing film system of PBAT/TPS/poly（propylene carbonate）（PPC）,DSC experiments showed that the addition of PPC could improve the molecular ordering of the film to a certain extent,such as orientation and crystallization.From the dynamic thermal mechanical analysis,PPC could also slightly improve the compatibility of PBAT/TPS/PPC.From the rheological experiment,it can be seen that the addition of PPC could reduce the composite viscosity of the blends,which could make processing easier.It was found that PPC could slightly reduce the tensile strength,but could increase the elongation at break from 200%to more than 350%.The young’s modulus increased with the increase of PPC composition.The results of morphology analysis showed that the toughness of the film was improved by the addition of PPC.The compatibility of the film and the dispersion of TPS were the best when the proportion of PBAT/TPS/PPC is 65/35/20.The contact angle test showed that PPC was hydrophilic,but the blend film was not greatly affected.The degradation experiments showed that PPC could accelerate the degradation of the film because of the improvement of starch dispersion.It could be concluded from the water vapor permeability test that the addition of PPC could improve the barrier performance of the film,which also increased with the increase of the PPC composition.Compared without PPC,the water vapor permeability of the film with 40 phr PPC was reduced by50%,reaching 1.562×10^-13g·cm/cm²·S·Pa.