Mesogenjacketed liquid crystalline polymers mjlcps with both electrontransport oxadiazole and holetransport thiophene in the side chain were reported for their promising electroluminescent property. With additional research, scientists later came to know that lcs are also formed from more complex polymeric molecules. In this study, mainchain liquid crystalline polyurethane lcpu that contains polar groups was synthesized. Mesogenjacketed liquid crystalline polymers substituted. Liquid crystalline polymers lcps have attracted longstanding attention for their outstanding. Chapter 5 deals mainly with mechanical performance in fiber and composites. Synthesis and characterization of a series of new liquid crystalline copolyesters containing biphenylester sulfone y. Influence of alkoxy tail length and unbalanced mesogenic. As their name indicates, liquid crystal polymers or lcps are derived from lcs to exploit their remarkable properties.
Here, we synthesized two phasmidic molecules msn, n 8, 12, where n is the carbon number of each alkyl tail. Liquid crystalline polymers xinjiu wang, qifeng zhou. Liquid crystallinity in polymers may occur either by dissolving a polymer in a solvent lyotropic liquidcrystal polymers or by heating a polymer above its glass or melting transition point thermotropic liquidcrystal polymers. Liquid crystals, side chain polymers, polymer modification. Its unique molecular architecture allows one to tune the geometric parameters of the macromolecular rod. Synthesis and liquid crystalline properties of mesogenjacketed polymers with different polymer backbonej.
It was found that the introduction of polar or polarable group at the end of the mesogen units could increase the melting point and clear point of monomers. Pdf mesogenjacketed liquid crystalline polymers via stable free. Phase behavior of phasmidic mesogenjacketed liquid. In solid form the main example of lyotropic lcps is the commercial aramid known as kevlar. Synthesis of mesogenjacketed liquid crystalline polymers. The 2006 edition of this authoritative guide on liquid crystalline polymer lcp science was produced in response to the wealth of new material generated in the field. Liquid crystalline polymers university of texas at austin. The mesogenjacketed liquidcrystalline polymers mjlcps in which the mesogenic units are laterally attached to the polymer main chain with or without short. Chemical journal of chinese universities, 1999, 2011. High molar mass liquid crystalline polymers have been primarily used in polymer blends as processing aids and as.
The orientation of liquid crystal molecules could be influenced by application of an electric field. Sidechain jacketed liquid crystalline polymer forming. Ptm et al, synthesis and characterization of a semiflexible liquid crystalline polyester with a broad nematic region, liquid crystals, 17, 811826 1994. The synthesis and property of a new series of mesogen. Chinese journal of polymer science 2018, 36 7, 811821. Liquidcrystal polymers are present in meltedliquid or solid form. In order to improve the hightemperature performance of thermoplastic elastomers tpes, we designed and synthesized a new kind of aba triblock copolymer containing a mesogenjacketed liquid crystalline polymer mjlcp, poly2,5bis4methoxyphenyloxycarbonylstyrene pmpcs, as the hard blocks and polybutadiene pb as the soft block. Low molar mass liquid crystals have been used as plasticizers for thermoplastic polymers and in applications such as electrooptics, optical recording media, and membranes. Polymers free fulltext enhancement in mechanical and. The effects of mesogenic groups, structural unit, substituents and flexible spacers on the.
A chapter on liquid biopolymers has been introduced, whilst the indepth discussion on. They exhibit a semi rigid, nearly linear, stacked orientation of molecules which stay highly ordered even in the liquid crystal phase as shown in fig. Us20030181618a1 liquid crystalline polymer films of. In previous work in this system, short alkyl chains have been used and. It is the second example of mesogenjacketed liquid crystalline polymer mjlcp prepared by atrp. Mesogenjacketed liquid crystalline polymers via stable. Drexel nanotechnology institute and department of materials science and engineering, drexel.
In order to improve the hightemperature performance of thermoplastic elastomers tpes, we designed and synthesized a new kind of aba triblock copolymer containing a mesogen jacketed liquid crystalline polymer mjlcp, poly2,5bis4methoxyphenyloxycarbonylstyrene pmpcs, as the hard blocks and polybutadiene pb as the soft block. The effects of chemical structure and steric features on liquid crystalline phase forming were studied. Mjlcps can selforganize into supramolecular columnar phases with the polymer chains ali. Mesogenjacketed liquid crystalline polymers chemical society. Fluorinated mesogenjacketed liquidcrystalline polymers as surfacemodifying agents. Behaviors of mesogenjacketed liquid crystalline polymers zheng xiang, sheng chen, yongbing luo, ping li, hailiang zhang key laboratory of polymeric materials and application technology of hunan province, key laboratory of advanced functional polymer materials of colleges and universities of hunan province, college of chemistry. Phase structures of a series of bentcore mesogen jacketed. Liquid crystals lc two types thermotropic phase transitions occur as temperature changes aromatic polyesters lyotropic phase transitions are a function of concentration and temperature aramids mesophases nematic smectic a, smectic c others liquid nematic smectic a smectic c crystalline wang, x zhou, q. Influence of alkoxy tail length and unbalanced mesogenic core on phase behavior of mesogen. As typical of sfrp reactions, it was observed that the molecular weight of the growing polymer chain gradually.
Moreover, the rod surface chemistry can be controlled by designing the. Conventional shape memory polymers suffer the drawbacks of low thermal stability, low strength, and low shape recovery speed. Sidechain liquidcrystalline polymers containing the siloxane spacer v. Mesogen jacketed liquid crystalline polymers mjlcps represent an important class of shapepersistent polymers. These polymers have aromatic amide structures as the mesogenic groups and are represented by poly. A series of mesogenjacketed liquid crystalline polymers, poly 2,5bis4alkoxybiphenyloxycarbonylstyrenes pcm, m 8, 10, 12, 14 and 18 were designed and successfully synthesized via free radical polymerization. Moreover, the rod surface chemistry can be controlled by designing the peripheral groups of the lateral mesogens. Liquid crystalline behavior of polymers medcrave ebooks. Design, synthesis, and characterization of bentcore. The second chapter is related to the theoretical description of liquid crystalline polymers, networks, and gels, which deals with subjects such as the formation of liquid crystallinity in the polymer system, the phase transition and phase diagram, the molecular weight effect, chain conformation, physics properties, etc. The difference with traditional side chain polymers is that in this case mesogenic groups are laterally attached see also section 2. Pdf block copolymers containing mesogenjacketed liquid crystalline polymers as rod blocks. In addition, a detailed study about liquid crystalline polymers lcps have. Front matter liquid crystalline polymers the national.
Lcps have a highly crystalline molecular chain in comparison to most common polymers such as abs and nylon. Liquid crystalline polymers world scientific publishing. From synthesis to structurephase transition behavior relationships. Chapters 5 and 6 summarize the properties and applications of liquid crystalline polymers. Mesogenjacketed liquid crystalline polymers via stable free radical polymerization 2341 able to control both the resulting molecular weight of each pbbos sample and monomer conversion by length of reaction time fig.
Influence of lc content on the phase structures of side. The molecular characterizations of the polymers were performed with 1 h nmr. Mesogenjacketed liquid crystalline polymers mjlcps, which were first. Design, synthesis, and characterization of bentcore mesogen. For the first time, bclc mesogens were directly sideattached to the polymer backbone and bentcore mesogenjacketed liquid crystalline polymers bmjlcps were achieved. Selfassembly and properties of block copolymers containing mesogenjacketed liquid crystalline polymers as rod blocks. In this chapter, liquid crystalline polymers are defined, methods for their characterization are described, and some examples of liquid crystalline polymers are discussed. This book introduces anisotropic innovations in liquid crystalline polymers as well as new nanocomposite materials and testing techniques. Synthesis and liquid crystalline properties of mesogen. Liquidcrystalline properties of comblike polymers prepared by homo and copolymerization with styrene of liposaccharidic monomers b. This 12chapter book emerged from lectures presented during the seminar polymer liquid crystals. We report the design, synthesis, and characterization of a series of mesogenjacketed liquid crystalline polymers with bentcore liquid crystals bclcs.
Sidechain liquidcrystalline polymers containing the. It takes the reader through the theoretical underpinnings to realworld applications of lcp technology in a logical, wellintegrated manner. Xiaofang chen, zhihao shen, xinhua wan, xinghe fan, erqiang chen, yuguo ma and. The chemical structures of the monomers were confirmed by 1 h nmr, 1 3 c nmr and mass spectrometry. Effects of molecular weight on liquidcrystalline behavior of a. This is in comparison to the molecular structure of abs and nylon which. Xiaofang chen, zhihao shen, xinhua wan, xinghe fan, erqiang chen, yuguo ma and qifeng zhou beijing national laboratory for molecular sciences, key laboratory of polymer chemistry and physics at the ministry of education, college of chemistry and molecular engineering, peking university, beijing 100871, china. Mesogenjacketed liquid crystalline polymers xiaofang chen, zhihao shen, xinhua wan, xinghe fan, erqiang chen, yuguo ma and qifeng zhou received 1st october 2009. Mesogen jacketed liquid crystalline polymers chemical. For a mjlcp, the mesogenic pendants are connected laterally to the polymer backbones with no or very short spacers. Mesogen jacketed liquid crystalline polymers chemical society.
White and ptm, a comparison of ultrasonic and thermal cure monitoring of an epoxy resin, composite polymers, 4, 403422 1991. Polymer liquid crystals covers the significant developments in the field of highlight oriented polymers. Advances in processing of lcps could permit the incorporation of these polymers into other than uniaxial designs and extend their utility into new areas such as nonlinear optical devices. Polysiloxanebased side chain liquid crystal polymers. Below is the uncorrected machineread text of this chapter, intended to provide our own search engines and external engines with highly rich, chapterrepresentative searchable text of each book. Mesogenjacketed liquid crystalline polymers chemical. Mesogenjacketed liquid crystalline polymers mjlcps represent an important class of shapepersistent polymers. Strain induced homeotropic alignment in the smectica phase of liquid crystals. Graphene oxide golcpu composite was fabricated using the solution casting method. Synthesis and properties of mesogenjacketed liquid crystalline.
Mesogenjacketed liquid crystalline polymer mjlcp is a typical rodshaped macromolecule. Fluorinated mesogen jacketed liquid crystalline polymers as surfacemodifying agents. So called mesogenjacketed liquid crystalline polymers have been. Read synthesis of mesogenjacketed liquid crystalline polymers with long symmetry mesogenic core containing two biphenyls, polymer on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. A study of the relationship between chemical structure and. Guoliang jiang, huanhuan cai, zhihao shen, xinghe fan and qifeng zhou, influence of fluorinated substituent and terminal length on phase behavior of mesogen. Synthesis and phase structures of combined mainchainsidechain liquid crystalline polymers with differentnumber azobenzene moiety in the sidechain based on mesogenjacketed liquid crystalline polymers. Pdf mesogenjacketed liquid crystalline polymers researchgate. Liquid crystalline polymer films of polymers of having azobenzene mesogenic groups in cross linked network structures, process for the preparation thereof, polymers and novel monomers having azobenzene mesogens download pdf info publication number us20030181618a1. Mesogenjacketed liquid crystalline polymers with a. Science and technology, held at santa margherita ligure, italy on may 1923, 1981. Mesogenjacketed liquid crystalline polymers mjlcps1 represent a kind of special polymers which attracted increasing interest in these years. Polyvinyl benzoate backbone mesogenjacketed liquid crystalline polymers hong yang, youjing lv, ming xu, jun wang, baoping lin, lingxiang guo, and erqiang chen, school of chemistry and chemical engineering, jiangsu province hitech key laboratory for biomedical.
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