Study On The Fabrication And Properties Of PBS Composites

Nowadays,the frequent occurrence of white pollution and oil crisis in our daily life has alerted people has alerted people that they can no longer use non-renewable resources without restraint,scientists have been thinking of various ways to solve the environmental pollution problem caused by plastic products,one of the mainstream direction is to develop biodegradable materials to replace the use of traditional petroleum-based plastics.Poly(butylene succinate)(PBS)has the advantages of excellent biodegradability,easier processing and higher tensile strength among many biodegradable materials,but it is necessary to modify and reduce the cost of PBS in order to completely replace traditional plastic products.In this paper,PBS was plasticized by bio-based plasticizers,and then modified with thermoplastic starch(TPS)as a filler material blended with PBS to achieve cost reduction,finally Poly(butylene adipate-co-terephthalate)grafted glycidyl methacrylate(PBAT-g-GMA)was added to the PBS composites to improve the interface between the phase regions and enhance the mechanical properties of the composite materials,and the specific research methods and conclusions are as follows:(1)Isosorbide/isooctanol adipate(IEDA)bio-based plasticizer was synthesized by esterification of isosorbide,adipic acid and isooctanol using solution polymerization method,and its structure was analyzed and verified through nuclear magnetic resonance ~1H-NMR and Fourier infrared spectroscopy FTIR analysis,which proved the successful synthesis of the product.A range of PBS/IEDA composite materials were produced by modifying PBS with the IEDA.The relationship between the addition of IEDA and its properties was investigated by conducting mechanical,crystallographic,rheological and phase structure tests on the PBS/IEDA blended products.The following conclusions are drawn:With the increase of IEDA content,the tenacity of the composite materials is improved,where the small molecule IEDA acts as a lubricant in the system,making the molecular chain segments less prone to entanglement.The notched impact strength reaches a maximum of 120 J/m raised by 70%at a content of 10%;T_g decreases by 8.7°C and crystallinity decreases by22.52%at 20%content.PBS processing torque and viscosity,energy storage,loss modulus are subsequently reduced with higher IEDA content,which reflects its better processing performance.The fracture behavior of the composite materials was found that there was a clear brittle-tough transition process by SEM testing,and the system showed a pore structure at higher IEDA content,and that the changes in microscopic morphology were consistent with the trends of mechanistic property testing.(2)Thermostatic starch(TPS)was produced by processing the synthesized IEDA with starch(St),and then St and TPS were mixed with PBS to prepare a series of PBS/St and PBS/TPS composite materials.From the mechanical,dynamic mechanical and thermodynamic tests of the composite materials,as well as the observation of the crystallization and phase structure,the following conclusions can be drawn:The impact strength of PBS/TPS is better than PBS/St,and this trend is getting stronger with increasing addition amount.The impact strength of PBS/St was 31 J/m at 30%addition,while the impact strength of PBS/TPS reached 45.5 J/m,which was 46.8%higher than the former.Tensile strength reaches a maximum of 38.55 MPa when TPS is added at 15%increase of12.8%.T_g(The glass transition temperature)of the composite materials showed a decreasing trend,reaching a minimum value of-26.6°C at 50%TPS addition,when the crystallinity nearly unchanged.SEM(scanning electron microscopy)observation of the impact section shows a significant improvement in the dispersion and compatibility of the TPS system compared to St in PBS.(3)A series of PBS/TPS/PBAT-g-GMA composite materials were produced by using polybutylene adipate-terephthalate grafted glycidyl methacrylate(PBAT-g-GMA)as a compatibilizer and toughening agent and blending with a fixed ratio of PBS and TPS.From the mechanical and dynamic mechanical tests of the composite materials,the crystallization and the observation of the phase structure,the following conclusions can be drawn:The impact strength gradually increased with the increase of PBAT-g-GMA content,and reached96.43 J/m at 50%PBAT-g-GMA content in the matrix,which increased by 180.41%.Both the tensile strength and modulus showed a decreasing trend,with the tensile strength and modulus decreasing by 38%and 43.99%respectively.Not only that,T_g(the glass transition temperature)and crystallinity of the composite materials also showed a decreasing trend,with T_g decreasing by 4.9°C and crystallinity decreasing by 21.1%.The observation of the impact cross section of the system clearly shows that PBAT-g-GMA improves the interfacial relationship and enhances the compatibility of the two phases.