Study on Properties of Nano-kaolin and PBS/Poly(3HB-co-4HB)Blends

Author:Tang Yi Xiang

Supervisor:lou bai yang

Database:Doctor

Degree Year:2013

Download:21

Pages:115

Size:10529K

Keyword:

Poly(butylene succinate)(PBS)is the most economically competitive polymer among the biodegrable polymers,which can be degraded by bacteria in soil and are so-called environmentally friendly polymer.PBS has several interesting properties,including biodegradability,melt processability,and chemical resistance,which gives rise to wide potential applications.However,other properties of PBS pose shortcomings,such as insufficient stiffness,low-melt strength and viscosity.and poor mechanical and thermal properties.In this paper,the research progress and application of PBS were outlined.Based on the previous work,the modification of PBS has been done.In the study,based on polymer melting blending,the resultants of modified PBS were characterized by Fourier Transform Infrared spectrometry(FTIR),DSC(Differential Scanning Calorimeter),scanning electron microscope(SEM),rotational rheometer,and the properties such as mechanical,crystallization,rheological behaviour and degrade properties of the modified PBS were also studied.The main contents and conclusions were shown as follows:1.Preparation and properties PBS/nano-kaolin:PBS/nano kaolin blends were prepared by mechanically melting mixing.The microstructure,crystallinity,mechanical properties and the characters of PBS/nano kaolin were studied.Infrared spectrometer(FT-IR)picture shown that the modifier could be bonded to nano kaolin.The DSC results indicated that the onset(denoted as To,c),peak(denoted as Tp,c)and end crystallization temperature(denoted as Te.c)of PBS were increased respectively.DSC melting curves for the melt-crystallized samples were obtained at 10Kmin-1.Double endothermic peaks,a high-temperature peak H and a low-temperature peak L,and an exothermic peak located between them appeared.At the same time,the crystallization degree rose firstly and declined finally as the nano kaolin content increased.When the content of nano kaolin is lesser,the notched impact strength,elongation at break and tensile strength of PBS/nano kaolin blends were improved obviously by mechanical properties testing.However,it is greater,their properties decreased in a way.The SEM shown that a little of nano kaolin was dispersed evenly in the blends,there existed agglomeration in blends on the contrary.The experimentation of Soil buried degradation indicated that with the content of nano kaolin increased,when the degradation period exceeded 60 days,the degradation property of PBS/nano kaolin blends improved obviously.At last,the rheological behaviors of the blends depended on temperature and the content of nano kaolin and showed strong thinning behavior and non-terminal viscoelastic behavior.2.Preparation and properties PBS/Poly(3HB-co-4HB):In order to improve the combinatorial performance of(PBS)/(Poly(3HB-co-4HB),the blends were prepared by mechanically melting mixing.The crystallinity,rheological behavior and mechanical properties of the PBS/Poly(3HB-co-4HB)were studied respectively with differential scanning calorimeter(DSC),rheometer and universal material testing machine.Mechanical property test showed that when the mass ratio of the sample were 95:5 and 90:10,the tensile strength and elongation at break of PBS/nano kaolin blends reached the maximum,respectively.The DSC results indicated that the onset(denoted as To,c),peak(denoted as Tp.c)and end crystallization temperature(denoted as Te.c)of PBS were increased respectively.The rheology experiments indicated the storage modulus(G’)and loss modulus(G")increased significantly with the increase of frequency.However,elongation at break and tensile strength of PBS/Poly(3HB-co-4HB)blends were declined clearly.After the blends were buried in the soil 60.210 days,weight loss rate of several specimen was higher.At the same time,with the increase of the content of Poly(3HB-co-4HB),the degradation performance of blends was better than pure PBS’s.3.Preparation and properties:PBS/Poly(3HB-co-4HB)/nano-kaolin blends were prepared by mechanically melting mixing.The mechanical and degradation properties and rheological behaviors of the PBS/Poly(3HB-co-4HB)/nano-kaolin were studied respectively with universal material testing machine,rheometer and scanning electron microscope(SEM).The mechanical properties testing of universal material testing machine shown that the relative mass ratio of nano-kaolin is 8,the notched impact strength and elongation at break of PBS/Poly(3HB-co-4HB)/nano-kaolin blends were improved obviously.However.the relative mass ratio of nano-kaolin increased,their properties decreased in a way.At the same time,the tensile strengths of PBS/Poly(3HB-co-4HB)/nano-kaolin blends were declined clearly.The SEM shown that degradation performances of PBS/Poly(3HB-co-4HB)/nano-kaolin(100/10/12)were favorable.The weight loss ratio of this sample was 64%.The rheology experiments indicated the storage modulus(G’)and loss modulus(G")increased significantly with the increase of frequency.