Study On The Preparation And Properties Of PLA Acid Blends

Polylactic acid(PLA)is a thermoplastic aliphatic polyester,which is a renewable resource.It has excellent biodegradability,biocompatibility,good mechanical properties and processability.For these reasons,PLA is expected to reduce the impact of petrochemical polymer production and use on the environment,and is widely used in biomedical materials and ordinary plastics.However,the brittleness of PLA limits its wide application.The toughening of PLA has been studied for a long time and many methods have been used to improve the toughness of PLA.For example,polylactic acid is mixed with other more flexible and biodegradable polymers such as PCL,PBS,poly 3-hydroxybutyrate(PHB)and poly(butylene terephthalate)-co-adipate(PBAT).However,because of the poor interfacial bonding between the phase separation and the two incompatible components,the poor impact resistance of the materials prepared by the simple blending is still poor.Therefore,the preparation of PLA and isosorbide two hexyl ester(DHDIC)blends and the blending of PLA and GPOE were studied.First,isosorbide two hexyl ester(DHDIC)was used to blend with polylactic acid(PLA),and the mechanical properties,rheological properties and processing properties of the blends were investigated by tensile,rotational rheology and differential scanning calorimetry(DSC).With the increase of DHDIC content,the tensile strength of PLA/DHDIC blends decreased and the elongation at break increased,showing the typical properties of rubber plastic.The glass transition temperature of the blends was also reduced greatly,making the material with good processing properties.DHDIC could be used as a good environment-friendly plasticizer for PLA.Second,PLA/GPOE blends were successfully prepared by simple melt composites under different GPOE loadings.Through a series of testing methods,the compatibility,rheological properties,mechanical properties and crystallization behavior of PLA and GPOE blends were studied.The purpose of this work is to evaluate its compatibility,phase morphology,toughening mechanism and crystallization behavior of PLA/ GPOE blends.