- Liquid crystalline epoxy resin based on biphenyl mesogen: Thermal characterization
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An epoxy monomer of 4,4′-diglycidyloxybiphenyl (BP) was synthesized and cured with a tetra-functional amine, sulfanilamide (SAA), to produce novel liquid crystalline epoxy resins (LCERs). The thermal properties, liquid crystalline morphologies, and cure behavior of the monomer were studied using differential scanning calorimetry, wide angle X-ray diffraction, and polarized optical microscopy. The effects of curing condition on the glass transition temperature, coefficient of thermal expansion, and dynamic mechanical properties of the resins were determined through thermomechanical analysis and dynamic mechanical analysis, respectively. The effects of cure condition on the formation of the liquid crystalline phase were also examined. The results show that BP is not a liquid crystalline epoxy monomer and an irreversible crystal transition exists in the temperature range of 120 C-140 C. The use of SAA results in the formation of a smectic liquid crystalline phase. Compared to the resins cured into an amorphous network, the LCERs exhibited a polydomain structure with individual liquid crystalline domain distributed in the resin matrix, which results in better thermomechanical properties.
- Li, Yuzhan,Badrinarayanan, Prashanth,Kessler, Michael R.
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- Liquid crystal epoxy photosensitive resin and preparation method thereof
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The invention discloses a liquid crystal epoxy photosensitive resin and a preparation method thereof. A mesogen-containing element and an end portion with - OH were formed. Epichlorohydrin and catalyst mix, access N2 The protective solution is reacted 40 - 100 °C to give a solution A. NaOH To Solution A, the reaction-generated water was removed, the reaction 0.1 - 4 hours was continued to remove NaCl, and the resulting filtrate was filtered to remove excess EHC to give a solution B. The solution B was mixed with a methanol/acetone solution, cooled and crystallized, and the resulting crystals were washed with methanol and suction filtered. Is dried to give a liquid crystalline epoxy photosensitive resin. The liquid crystal epoxy photosensitive resin provided by the invention has the advantages of orderly liquid crystal ordering and network crosslinking, so that the liquid crystal epoxy resin has excellent light, electrical performance and better thermo-mechanical performance.
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Paragraph 0018; 0032; 0034-0036
(2021/12/07)
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- Using the liquid crystalline epoxy resin thermoset aromatic diamine
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PROBLEM TO BE SOLVED: To provide an aromatic diamine that gives a heat-cured product useful as an electric insulation material for radiating the heat generated from a semiconductor element and the like, and a liquid crystalline epoxy resin heat-cured product prepared therewith.SOLUTION: This invention relates to an aromatic diamine represented by formula (1), and a heat-cured product of the diamine and a liquid crystalline bisepoxide represented by formula (2) (where R-Rindependently represent a hydrogen atom, a C1-C6 alkyl group or a C1-C6 alkoxy group, m is an integer of 2-14, and Xis a divalent aromatic group).SELECTED DRAWING: None
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Paragraph 0046-0048
(2020/08/26)
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- BISPHENOL DERIVATIVE THERAPEUTICS AND METHODS FOR THEIR USE
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This invention provides compounds having a structure of Formula (I). Uses of such compounds for treatment of various indications, including prostate cancer as well as methods of treatment involving such compounds are also provided.
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Page/Page column 97-98
(2011/08/03)
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- Synthesis, characterization, and thermal properties of diacrylic/ divinylbenzene copolymers
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In this article, synthesis, characterization, and thermal properties of diacrylic/divinylbenzene copolymers based on the new aromatic tetrafunctional acrylate monomers are presented. The new monomers were generated by treatment of epoxides derived from various aromatic diols: naphthalene-2,3-diol (NAF), biphenyl-4,4′-diol (BIF), bis(4-hydroxyphenyl)methanone (BEP) or 4,4′-thiodiphenol (BES), and epichlorohydrin with acrylic acid. The addition reaction was carried out by a ratio of 0.5 mol of suitable epoxy derivative and 1 mol of acrylic acid in the presence of 0.7 wt% of triethylbenzylammonia chloride (TEBAC) as a catalyst and 0.045 wt% of hydroquinone as a polymerization inhibitor. The chemical structure of the prepared acrylate monomers was confirmed by 13C NMR and GC MS spectra. The emulsion-suspension polymerization of acrylate monomers with divinylbenzene (DVB) in the presence of pore-forming diluents (toluene + decan-1-ol) allowed obtaining microspheres containing pendant functional groups (hydroxyl groups). This process was carried out at constant mol ratio of acrylate monomers: DVB (1:1), and constant volume ratio of pore-forming diluents to monomers (1:1). The different concentrations of toluene in the mixture with decan-1-ol were used for qualifying the effect of the diluents on the microsphere characteristics. The influence of synthesis's parameters on the properties of copolymer beads, e.g., pore size and surface area by BET method, the surface texture by AFM, swelling behavior in polar and non-polar solvents as well as thermal stability by differential scanning calorimetry (DSC), and thermogravimetric analysis (TG) was studied and discussed.
- Podkoscielna, Beata,Worzakowska, Marta
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experimental part
p. 235 - 241
(2010/09/17)
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- Synthesis and plant growth retardant activity of bis-quaternary salts of ammonia from phenols
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Trialkylamines 3-(2-benzylphenoxy)-l-N,N-diethylaminpropan-2-ol (4a), 3-(4-benzylphenoxy)-l-N,N-diethylaminpropan-2-ol (4b), 3-(5-n-hutoxyphcnoxy)-l- N,N-diethylaminpropan-2-ol (4c) and 4,4'-bis(3-N,N-diethylamin-2- hydroxypropanoxy)biphenyl (9) were prepared from respective phenols and converted into corresponding bis-quaternary salts by reacting (4a-c) with malonyl chloride and (9) with ethyl bromide. These salts were tested for biological activity on germination, seedling growth and adventitious root formation on hypocotyl cuttings of Vigina radiata (SML-668). The results of biological studies of different compounds show that these salts do not inhibit seed germination and rather promotory in increasing shoot elongation if used from 10-50 μg/ml. However, all those compounds showed inhibitory action at higher concentration i.e. 100 μg/ml.
- Sharma,Bala, Madhu
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p. 975 - 977
(2007/10/03)
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- Liquid crystalline epoxy thermosets
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Rigid rod epoxy compounds can be cured in liquid crystalline structure. The so obtained networks exhibit better mechanical properties with respect to the isotropic ones. The mesogenic character of the epoxy compounds appears more crucial than the molecular geometry of the curing agent in developing liquid crystallinity. The curing temperature plays an important role in affecting the state of order of the thermosets.
- Giamberini,Amendola,Carfagna
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- Mesogenic adducts
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An adduct is prepared by reacting (A) a compound containing at least one epoxy group per molecule, with (B) a compound containing at least one epoxide reactive group per molecule selected from the group consisting of phenolic, thiol, secondary amine and carboxyl; wherein (i) when compound (A) is a polyepoxide, compound (B) contains a single epoxide reactive group per molecule; (ii) when compound (A) is a monoepoxide it is a monoglycidyl ether and compound (B) contains at least two epoxide reactive groups per molecule; and (iii) at least one of components (A) and (B) contains a rodlike mesogenic moiety. These adducts are useful in the preparation of polyurethanes.
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