| 2013th Bachelor |
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Title:Synthesis and Characterization of A Novel Hydrogen-bonded Supramolecular Polymer Writer: Luchong Zhang Supervisor: Wei Wu, Yujie Chen Abstract:Supramolecular systems are broadly defined as multi-component molecular assemblies， in which the components are held together by a variety of weaker non-covalent interactions， such as lipophilic interactions ，π-π stacking and hydrogen bonding as well．Among these interactions， hydrogen bonding is appealing from reversible assembly of the complicated and functional supramolecules because of the moderate strength， high directionality and specificity． Many supramolecular systems had been previously constructed on the basis of hydrogen bonding arrays．In this study，we synthesis a new supramolecular polymer based on the 2-ureido-4 -[1H]-pyrimidone(UPy)，which is the copolymer of A6ACA and SCMHBMA．Then，we take the FT-IR，1HNMR to indicate the polymer，as well as thermo-analysis to invest the properties．Later we find the usual properties of polymers but with the UPy，which can make a difference for the investigation of self-healing hydrogel in future．
Title:Formation and Characterization of Self-assembled Films from PAMAM Dendrimers Writer:Xuewei Zhang Supervisor: Wei Wu, Yong Zhong Abstract:In this study, the modification of hydroxyl-terminated silicon with unsaturated organic molecules by forming self-assembly monolayer and multilayer has been investigated. The aim is to prepare nano-sized films with a smooth surface. First of all, functional monolayers were prepared by four different methods, including deposition, coating, adding electrolyte solutions and changing pH. Subsequently, multilayers were formed by attaching polystyrene sulfonate (PSS) molecules and polyamidoamine(PAMAM) dendrimer alternately to the surface. Atomic force microscopy (AFM) and UV-vis are used to characterize these functional monolayers and multilayers, including the structure, morphology and thickness, which will contribute to carrying out performance test and functional application of the film.
Title:A Research on Expansion-Type Flame Retarding TPEE with Phenolic Resin as Charring Agent Writer:Haisu Wang Supervisor: Wei Wu, Yuhua Zhong Abstract:During the experiment, a halogen-free expansion-type flame-retarding TPEE(Thermoplastic Polyether-ester Elastomer) was prepared, with its flame retardant rating UL94-V0, LOI value 28.9. It exhibited its good flame-retardany. By FTIR infrared testings and dynamic real-time infrared testings, we used pyrolysis mass spectrometry to explore their different thermal decomposition mechanism and phenolic resin charring mechanism with their formulations varied.Thermogravimetric analysis and SEM-EDX showed that under high temperature the introduction of phenolic resin will increase its residue as well as carbon content in residue. At the same time, SEM tests suggested that the introduction of the phenolic resin will be helpful in forming a dense carbon layer and achieving a good anti-droplet effect.
Title:Flame Retardant TPEE Preparation and Thermal Decomposition Kinetics Writer: Zhongjian Song Supervisor: Wei Wu, Yuhua Zhong Abstract:With the polymer material being used more and more widely in daily lives. To give polymer materials with excellent flame retardant performance has become hot-spot research topic. This article describes an overview of flame retardants and trends; describes the different properties of a variety of flame retardants; introduces several thermal decomposition kinetics of research methods. Using optimization theory and methods, focus on synergy between the complex components, optimizing the composition of the intumescent system, then obtain the desired intumescent formulations and prepare TEPP materials with good flame retardant properties. Experiments mainly includes two aspects: Preparation and characterization of modified flame retardant of TPEE. Adding the novolac with the phosphorous-nitrogen sysetems through melt blending prepared flame retarding TPEE. Through different thermal decomposition kinetics equation, calculating the decomposition activation energy and pre-exponential factor decomposition function types of the system.
Title:C60 derivatives with Hydrogen Bonding Supramolecular Aggregates Synthesis and Characterization Writer: Weidong Xu Supervisor: Wei Wu, Yujie Chen Abstract:UPy (2 - ureido -4-1 [H] - pyrimidin-one) can be self-complementary quadruple hydrogen bonding to form dimmers. If the hydrogen structural unit to be modified by introducing a group of C60, it can be obtained with special optical properties of supramolecular systems. In this study, C60, after a series of organic synthesis reactions , generated C60 derivatives with four hydrogen bonds (Upy-C60-Upy). The structure of each reaction step was determined by using IR, UV, NMR, MS to clarify the reaction mechanism and to characterize the formation of multiple hydrogen bonds. In addition，characterized the banded structure morphology of Upy-C60-Upy supramolecular materials with AMF and TEM.
Title:Preparation and Properties of Antistatic PP/PANI-complex Blends Writer: Kai Luo Supervisor: Wei Wu, Qiaoling Luo Abstract:Polyaniline (PANI) as an antistatic polymer material，for its excellent conductive properties，and simple preparation and high electrical conductivity compared with other conductive polymers，is considered to be the most promising copolymers for practical use．With Doping polyaniline can greatly enhance their conductive properties，which has a high research value．In this paper，toluenesulfonic acid(TSA) has been used for doping PANI，prepared the doped PANI．By infrared spectroscopy，thermal analysis (TG)，conductivity test and analysis are used on characterizing doped polyaniline and results that TSA doping PANI can greatly enhance the conductivity of PANI．With doped PANI and PP for modification，hoping to prepare PP/PANI antistatic composite．Four components of blends have been prepared in this study， which are respectively PP / PANI mass ratios of 100/0，95/5，90/10 and 85/15．By extrusion and mixing blends respectively，and then through plate and injection to obtain the required test samples．By rheological performance test (torque rheometer)，mechanical testing，electrical performance testing on PP/PANI blends，the rheological properties，mechanical properties，electrical properties have been described and found that the volume resistivity of the blends decreased，but the tensile strength and the impact strength of a certain amplitude is reduced，and the bending strength is not affected．
Title:The Influence of The Crystallization on PET/PEN Blends System by Ionomer Writer: Yuanhao Sheng Supervisor: Wei Wu, Ren Wu Abstract:PET/PEN/Surlyn blends were studied in this paper in order to improve the crystallinity property of PET/PEN blends system by the ionomer (Surlyn resin). Due to the lack of mechanical properties, heat resistance and gas barrier properties, the industrial applications of PET is considerably limited. PEN has better performance than PET, but its price is much higher than PET. High cost performance can be obtained by blending PET with PEN. Because of the poor crystallization properties of PET and PEN, it's harder to crystallization after blending, so it's important to improve the crystallization properties of blends. In this paper the PET/PEN/Surlyn blends was prepared. The results of the blend were characterized by differential scanning calorimeter(DSC), polarizing microscope(POM), X-radial diffractometer(XRD), thermogravimetric analysis(TG) and universal testing machine. The study result shows that the addition of Surlyn not only sharply increases the crystallinity properties of PET and PEN, but also high temperature nucleation performance, crystallization velocity and degree of crystallinity of PET/PEN blend. Meanwhile the addition of Surlyn promotes the growth rate of PET/PEN.
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