Synthesis and Characterization of Polymers Based on Norbornene and Carbazole by Ring-Opening Metathesis Polymerization

• Main Authors: Chao-Chi Wang, 王照錡
• Other Authors: Chin-Yang Yu
• Format: Others
• Language: en_US
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/p424fq

博士 === 國立臺灣科技大學 === 材料科學與工程系 === 107 === Polymers can be prepared by ring-opening metathesis polymerization (ROMP) of strained monomers, initiated by ruthenium carbene initiator. The resulting polymers exhibited low polydispersities, low defect, controllable end group fashion and the molecular weight of polymers can be tightly controlled by changing the monomer to initiator ratio. In the research proposal, we employ ring-opening metathesis polymerization of highly ring-strained monomers such as alkyl, semi-perfluoroalkyl or triethylene glycol substituted norbornene-based derivatives and carbazolephanediene undergoing ruthenium carbene complexes which can generate a series of well-defined homopolymers and block copolymers. In addition, the molecular weight and the volume ratio of the individual blocks of the polymers can be tailored by the ratio of the monomers employed. Herein, we will use block copolymers and their analogous homopolymers prepared in a predictable manner that exhibits self-assembled nanoscale morphology. The study will focus on polymer synthesis and films generated by spin coating from various solutions and examine the morphology and the optical property based on structure directing block copolymers which may lead to potential use in organic photonic crystals or a photovoltaic device. The series of new monomers and polymers with different flexible chains have been synthesized and fully characterized by NMR, mass spectroscopy and gel permeation chromatography. The homopolymers and block copolymers can be obtained by the ring-opening metathesis polymerization of their corresponding monomers and comonomers using third generation Grubbs initiator. The self-assembly of polymers with the different side chains have been reported in this research. For norbornene-base polymers, fluorinated chains are thought to be easier to have self-assembled structure in polymer films due to the inimitable aggregation property. The block copolymer contains both fluorinated block and alkyl block shows different size particles with different volume ratio. A series full conjugated polymers were synthesis by carbazolephanediene. The monomers were synthesized by McMurry coupling in few steps. The bandgap of the carbazolevinylene base polymers is relatively low (2.64 to 2.79 eV) and is strongly dependent on the side chains. The carbazolevinylene block copolymers with a higher composition of the triethylene glycol substituted carbazolevinylene block showed sphere-like nanoaggregates due to the highly disorder and flexibility of the triethylene glycol chains. This work demonstrated well control of the polymer microstructures with specific nanoaggregates in solid state.