Study On Preparation Of PLA/PBS Reinforced Plastics By Volume Elongational Flow Extruder And Relations Of Its Structure And Properties

Blending modification is a major route to enhance performance of polymer materials.With the research and development of high performance polymer materials, the problems ofresources, environment and energy must be considered, in order to realize sustainabledevelopment of polymer industry. Therefore, it is a development trend to exploit a novel highperformance biodegradable polymer from renewable resource. One of the promising methodsof worth attention is employed to generate some deformed dispersed phase in situ duringbiodegradable polymer blending processing with physical and chemical means or externalfield change. This method puts forward a simple, effective and clean process to enhanceperformance of polymer materials.In this paper, PLA and PBS are applied. The PLA/PBS truly biodegradable in-situreinforced plastic are prepared by Vane Extruder and changes disadvantages of traditionalpetroleum in-situ reinforcement materials, which destroying ecology environment andresources. Furthermore, the mechanism of in-situ reinforcement is systematic investigated.Morphologies of prepared blends are characterized by scanning electron microscope (SEM).Differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), wide angleX-ray diffraction (WAXD) and dynamic mechanical analysis (DMA) are used to multiangularcharacterize the thermal behavior and crystalline structure of the blends. The mechanicalproperties of tensile, flexural and impact properties are examined. The results show that theincrease amplitudes of tensile modulus and flexural strength of blends are respectively30.3%and40.6%, and the PLA phase dispersed uniformly in PBS matrix displays oval shape andlong strip structure, implying that the in-situ reinforcement of blends was realized duringprocess.In addition, the blend prepared by Vane Extruder under initial higher temperaturefollowing by lower temperature process exhibit optimum tensile and impact properties, andthe PLA phase dispersed uniformly in PBS matrix displays oval shape and long strip structure.Moreover, the effect of hot press on morphology of blends is not detected. In addition, thedispersed phase of blends prepared by single screw extruder shows round shape in matrix, andthe tensile and impact properties are inferior to the blends of Vane Extruder, which impactstrength maximum increases by approximately69.31%.The analysis and testing show that the change of extrusion die head and extrusion ratehas great influence on the mechanical properties, crystallization behavior and morphology ofthe PLA/PBS blends. The blends associated with die head aspect ratio of15or extrusion rate of60rpm display ideal toughening and reinforcing effect. And the dispersed phase disperseduniformly in matrix displays oval shape and long strip structure.At a fixed technological process, with the increase of PLA contents, PLA phase in PBSmatrix was shown as fibrillar structure, and the flexural properties and Young’s modulus ofblends increased as well, which increase amplitudes of flexural strength is24.4%. However,the crystalline of PBS is not change after adding PLA. Furthermore, the DCP can improve theinterfacial adhesion between PLA and PBS phase and effect crystallization capacity of PBScomponent, resulting in the higher heat resisting properties, tensile strength, elongation atbreak and notched impact strength for cosslinked PLA/PBS blends, and the tensile strengthincreases maximum by16.87%. In addition, melt flow rate proportion of disperse phase andcontinuous phase exert an important role in morphology of disperse phase. Moreover, theresults indicate that the PLA displays oval shape and long strip structure in PBS when meltflow rate proportions of disperse phase and continuous phase are respectively7.72g/10minand4.5g/10min.