| Synthesis and design of functionalized polymers were studied based on the VPDMS with Si-H group as monomer. Through hydrosiliation, the liquid crystalline and photoelectric element groups were introduced into polymer chain with different structures and a series of functional materials were obtained. Meanwhile, the relationship between properties and structure of polymers was investigated systematically. The methodology for synthesis of functional materials was established.The study in this thesis conducts anionic polymerization homopolymerization based on functional monomer VPDMS and copolymerization with styrene, butadiene, isoprene, thus generates21different molecular weights of4series, namely parent polymer with different content of SiH functional groups. All the polymers are with clear structure, the molecular weight of which meets design requirements, and molecular weight distribution is relatively narrow (Mw/Mn<1.20). SiH group is stable during the polymerization without any loss. Under trace platinum catalyzing, there is a self-crosslinking reaction between the SiH group and double bond in the copolymer of butadiene/VPDMS and isoprene/VPDMS. A non-sulfur-cured elastomer is generated. Thermal properties of elastomer has been significantly improved comparing corresponding polymer.There are7type of chiral liquid crystal micro-molecules with cholesteryl of2series obtained in the study. The molecular structure is clear and meets design requirements. They present good liquid crystalline property and optical activity. Therefore, the influence of molecular structure on which is discussed in this thesis.This study used terminal vinyl double bond of liquid crystalline monomers and pre-build linear polymers with SiH group to conduct hydrosilylation reaction, then obtain12types of liquid crystalline functional polymer materials. All the products, are pure, without unreacted SiH group and excess liquid crystalline monomers. The molecular weight of products increase significantly, and the molecular weight distribution remains low statue. P2-3molecular weight reaches99,8000, meanwhile, the molecular weight distribution is only1.07. All the products are with good liquid crystalline property. The glass transition temperatures (Tg) of products substantially reduced comparing with parent polymer, while the clearing temperatures (Ti) rose considerably comparing with liquid crystal monomer. The liquid crystal phase range (△T) widen evidently, among them,△T of Pa is significantly higher21times than that of Ma, and△T of P4reached246.3℃. Meanwhile all the products present optical activity. The scanning electron microscopy indicates that liquid crystal polymer, overcame the defect of liquid crystal monomer annealing crystallization, could form a smooth surface. This type of polymer is expected to apply in multiple areas, such as optical devices and liquid crystal display. Based on the data above, this thesis discussed thoroughly the influence of changing side chain structure on liquid crystalline property and optical activity of products under the condition of same main chain, the influence of changing molecular weight on liquid crystalline property and optical activity of products under the condition of same main chain and side chain structure, and the influence of changing content of side chain on liquid crystalline property of products under the condition of same main chain and side chain structure.In the thesis, four arm star VPMDS homopolymer is compounded by using high vacuum anionic polymerization technology and syndiotactic VPDMS homopolymer is compounded by using scandium coordination polymerization technology. The structures of products are explicit, the molecular weights of which meet the design requirement and the molecular weight distribution is relatively narrow. The steric regularity of the syndiotactic polymer is99%. These two parent polymers demonstrated before combine with liquid crystal monomer Mi and M2, which generate4types of liquid crystal polymers with complex structure main chain. The products all possess fine liquid crystalline properties by characterized. Based on these data, this thesis presents a comparing discussion about the influence on liquid crystalline properties of products by changing main chain structure. Meanwhile, all the products possess optical activity.Isoprene/VPDMS copolymerization product, as parent polymer, take liquid crystal monomer M2into one-pot reaction, so that5types of self-crosslinking elastomer are produced. The test results show that, when junction content is lower then2mol%, there are no3D network structures and gel, when the content of crosslinks is higher then4.7mol%, the gel content maintain stable at approximate89%and all elastomer present liquid crystalline properties. The thesis made several discussions based on the laboratorial data:the changing trend of crosslinks and liquid crystal side chain content and the changing trend of elastomer Tg, Ti and△T with the changes of VPDMS content. The influence on liquid crystalline properties of cross-linking main chain struct is also discussed under the condition of same side chain.In the study of this thesis,2types of perylene bisimide derivatives are compounded. Combining them with parent polymer that of different molecular weight and main chain structures, there are8types of polystyrene semiconductor materials with perylene bisimide group on side chain generated. The spectral performance of them is characterized by ultraviolet spectrum and fluorescence spectrum in the study, the electrochemistry is characterized by cyclic voltammertry as well. The thesis also produces the fabricate BHJ with P3HT, as p-material, and functional polymer material, along with the study of the influence on solar cells performance by the liquid crystalline property, molecular weight and changing structure of polymer material. |
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