Crystalline Epoxy resin

Crystal lattice packing, 12 249-250 Crystal lattice vibrations, 14 236 Crystalline adsorbents, 1 586, 589. See also Molecular sieves Zeolites for gas separation, 1 631 properties and applications, l 588t Crystalline alkali silicates, atomic structure of, 22 454-455 Crystalline cellulose, 5 373-379 Crystalline epoxy resins, 10 373-374 Crystalline flake graphite, 12 793 manufacture and processing of, 12 781-784... [Pg.235]

Har Harada, M., Aoyama, K., Ochi, M. Influence of the loading rate on liquid-crystalline epoxy resin systems. J. Polym. Sci. Part B - Polym. Phys. 43 (2005) 1296-1302. [Pg.548]

Liquid crystals exhibit a partially ordered state (anisotropic) which falls in-between the completely ordered solid state and completely disordered liquid state. It is sometimes referred to as the fourth state of matter . In recent years, interest in liquid crystalline thermosets (especially liquid crystalline epoxy) has increased tremendously [33-44]. If the liquid crystal epoxy is cured in the mesophase, the liquid crystalline superstructure is fixed permanently in the polymer network, even at higher temperature. Liquid crystal epoxies are prepared using a liquid crystal monomer [33-38] or by chemical modification of epoxy resin [43] which incorporates liquid crystal unit in the epoxy structure. Liquid crystalline epoxy resins with different types of mesogen such as benzaldehyde azine [33], binaphthyl ether [34, 35], phenyl ester [36, 37] and azomethine ethers [38, 39] have been reported. Depending on the chemical nature of the mesogen, the related epoxies display a wide range of thermomechanical properties. The resins can be cured chemically with an acid or amine [40, 41] or by photochemical curing in the presence of a photo-initiator [3]. Broer and co-workers [42] demonstrated the fabrication of uniaxially oriented nematic networks from a diepoxy monomer in the presence of a photo-initiator. [Pg.176]

Partially crystalline epoxy resins considered in this paper have not yielded plastic flow at 4.2 K. [Pg.46]

Partially crystalline epoxy resins undergo less mechanical loss than amorphous ones. They are more like PE. The crystalline fraction has not yet been determined, but may well be similar to that of PE. [Pg.47]

The mechanical losses of partly crystalline epoxy resins were found to be lower than those for amorphous ones. First measurements also show a similar situation for dielectric low-frequency losses. The value plotted in Fig. 11 is an upper limit and the true value is probably lower. Further measurements are in preparation. However, despite the fact that plastic flow has not yet been found, because of their good dielectric properties, crystalline epoxy resins seem to be of advantage. [Pg.49]

This statement holds true especially in the case of liquid crystalline epoxy resins. In fact, the structural features and distribution of crosslinks along the molecular backbone strongly influences the liquid crystalline phase developed during the curing process and the performances and the applicability of the resulting material. [Pg.389]

Liquid Crystalline Epoxy Resins can be cured in different ordered states depending on the curing agent used. With aromatic amines the thermoset is crosslinked in a nematic structure. No isotropization temperature can be detected. The reaction can be monitored by means of DSC analysis. A double peak exotherm indicates that the crosslinking reaction forms a liquid crystalline resin. Kinetic models can be applied to separate the contributions of the different reactions. [Pg.401]

Crystalline Epoxy Resins Deveiopment. Anumber of new epoxy resins used in epoxy molding compoimds (EMC) have been developed by Japanese resin producers in response to the increased performance requirements of the semiconductor industry. Most notable are the commercialization of crystalline epoxies based on biphenol by Yuka-Shell (60) ... [Pg.2682]

Keywords Liquid crystalline thermosets, liquid crystalline epoxy resins, curing reactions, mechanical properties, thermal properties... [Pg.387]

Figure 11.7 Chemical structures of liquid crystalline epoxy resins with deferent mesogenic length. Reproduced from reference 27.

Figure 11.8 Chemical structures of naphthalene (a) and biphenyl (b) containing liquid crystalline epoxy resins. Reproduced from reference 28, 29.

Figure 11.21 2,2 -Bis(4-cyanatophenyl) isopropylidene (CE) and Liquid crystalline epoxy resin (LCE).

Issam AM, Mohd Fadhley A, Wan Rosli WD (2012) New class of liquid crystalline epoxy resins synthesis and properties. J Ind Eng Chem 18 364—372 Jackson WJ Jr, Kuhfuss HF (1976) Liquid crystal polymers. I. Preparation and properties of p-hydroxybenzoic acid copolyesters. J Polym Sci Polym Chem Ed 14(8) 2043-2058 Karayannidis GP, Archilias DS, Sideridou ID, Bddaris DN (2005) Alkyd resins derived from glycolized waste poly (ethylene terephthalate). Eur Polym J 41 201-210 Marin L, Cozan V, Bruma M (2006) Comparative study of new thermotropic polyazines. Polym Adv Technol 17 664—672... [Pg.314]

Liquid Crystalline Epoxy Resin Based Nanocomposite... [Pg.459]

Table 19.1 Chemical structures of conventional and liquid crystalline epoxy resins... [Pg.461]

Liquid Crystalline Epoxy Resin Based Nanocomposite Table 19.2 (continued)... [Pg.469]

Amendola E, Carfagna C, Giamberini M, Pisaniello G (1995) Curing reactions of a liquid-crystalline epoxy-resin based on the diglycidyl ether of 4,4 -dihydroxy-alpha-methylstilben. Macromol Chem Phys 196 1577-1591... [Pg.483]

Cai ZQ, Sun JZ, Zhou QY, Xu JL (2007) Synthesis and characterization of a novel liquid-crystalline epoxy resin combining biphenyl and aromatic ester-type mesogenic units. J Polym Sci Polym Chem 45 727-735... [Pg.483]

Carfagna C, Amendola E, Giamberini M (1994b) Liquid-crystalline epoxy-resins containing binaphthyl group as rigid block with enhanced thermal-stability. Macromol Chem Phys 195 2307-2315... [Pg.483]

Carfagna C, Aciemo D, Di Pahna V, Amendola E, Giamberini M (2000a) Composites based on carbon fibers and liquid crystalline epoxy resins, 1—Monomer synthesis and matrix curing. Macromol Chem Phys 201 2631-2638... [Pg.483]

Castell P, Sena A, Galia M (2004) Liquid-crystalline thermosets from liquid-crystalline epoxy resins containing bisazomethinebiphenylene the central core copolymerization with a nonmesomorphic epoxy resin. J Polym Sci Polym Chem 42 3631-3643 Chtm S, Hsu SH, Wu MC, Su WF (2011) Kinetics studies on the accelerated curing of liquid crystalline epoxy resin/multiwalled carbon nanotube nanocomposites. J Polym Sci Polym Phys 49 301-309... [Pg.484]

Giambtaini M, Amendola E, Carfagna C (1997) Lightly crosslinked liquid crystalline epoxy resins the effect of rigid-rod length and applied stress on the state of order of the cured thermoset. Mataomol Chem Phys 198 3185—3196 Grebowicz JS (1996) On the formation of liquid crystalline texture in epoxy resins. Macromol... [Pg.484]

Harada M, Ochi M, Tobita M, Kimura T, Ishigaki T, Shimoyama N, Aoki H (2003) Thermal-conductivity properties of liquid-crystalline epoxy resin cured under a magnetic field. J Polym Sci Polym Phys 41 1739-1743... [Pg.484]

Harada M, Watanabe Y, Tanaka Y, Ochi M (2006) Thermal properties and fracture toughness of a liquid-crystalline epoxy resin cured with an aromatic diamine crosslinker having a mesogenic group. J Polym Sci Polym Phys 44 2486-2494... [Pg.484]

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