Results 191 to 200 of about 36,585 (232)
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Macromolecular Chemistry and Physics, 2000
A series of liquid crystalline oligomers of 4-hydroxybenzoic acid (HBA) and 2-alkoxyHBAs were synthesized. The structural and conformational changes the oligomers were studied by FTIR spectroscopy. The strengthening abilities of the synthesized co-oligomers were investigated by blending the oligomers with polyamide 11 (PA 11).
Anu M. Moilanen, Osmo E. O. Hormi
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A series of liquid crystalline oligomers of 4-hydroxybenzoic acid (HBA) and 2-alkoxyHBAs were synthesized. The structural and conformational changes the oligomers were studied by FTIR spectroscopy. The strengthening abilities of the synthesized co-oligomers were investigated by blending the oligomers with polyamide 11 (PA 11).
Anu M. Moilanen, Osmo E. O. Hormi
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Whiskers of poly(4‐hydroxybenzoic acid) — preparative aspects
Die Makromolekulare Chemie, 1991AbstractPolycondensation of 4‐acetoxybenzoic acid (4‐ABA) at 300–400°C involves side reactions yielding a difficult to be hydrolyzed fraction of modified poly(4‐hydroxybenzoic acid) (poly‐HBA). Such side reactions are the formation of diphenyl ether groups, Fries‐rearrangement, formation of ketene or acetic anhydride and, possibly, isomerization to 3 ...
Hans R. Kricheldorf +3 more
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4-Hydroxybenzoic acid for multiple system atrophy?
Parkinsonism & Related Disorders, 2018Increasing evidence supports a link between multiple system atrophy and coenzyme Q10 (CoQ10) biosynthesis. However, so far this knowledge was not translated into tangible benefits for affected patients. Poor bioavailability of oral CoQ10 might constitute a major problem.
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ChemInform, 2009
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Sankar P. Dey, Dilip K. Dey
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AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Sankar P. Dey, Dilip K. Dey
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Journal of Liquid Chromatography & Related Technologies, 2006
Abstract A high performance liquid chromatography (HPLC) method for the assay of phenylformic acid, 2,4‐hexadienoic acid, methyl 4‐hydroxybenzoate, and propyl 4‐hydroxybenzoate preservatives was developed and validated. The use of a reversed‐phase C8 column using an isocratic elution system enabled four compounds to be separated simultaneously in one ...
Ghulam A. Shabir +3 more
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Abstract A high performance liquid chromatography (HPLC) method for the assay of phenylformic acid, 2,4‐hexadienoic acid, methyl 4‐hydroxybenzoate, and propyl 4‐hydroxybenzoate preservatives was developed and validated. The use of a reversed‐phase C8 column using an isocratic elution system enabled four compounds to be separated simultaneously in one ...
Ghulam A. Shabir +3 more
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Microbial production of specifically ring-13C-labelled 4-hydroxybenzoic acid
Applied Microbiology and Biotechnology, 1995When transformed with a recombinant vector carrying the ubiC gene (encoding chorismate pyruvate-lyase, EC 4.1.3.27) the triple mutant (Phe-, Trp-, Tyr-) Klebsiella pneumoniae 62-1 excretes 4-hydroxybenzoic acid instead of chorismic acid. The recombinant strain can be used to produce in high yield specifically ring-labelled 4-hydroxybenzoic acid from ...
R, Müller +3 more
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Copolyesters of 4-hydroxy-3-phenylbenzoic acid and 4-hydroxybenzoic acid
Polymer, 1992Abstract Crystalline poly(3-phenyl-4-hydroxybenzoic acid) was prepared by polycondensation of 4-acetoxy-3-phenylbenzoic acid in solution at 320°C. Differential scanning calorimetry (d.s.c.) and wide angle X-ray scattering (WAXS) measurements indicate that this homopolyester forms a nematic melt between 345°C and 465°C.
Hans R. Kricheldorf, Frank Ruhser
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3-[(2-Aminoethyl)iminomethyl]-4-hydroxybenzoic Acid 0.28-Hydrate
Acta Crystallographica Section C Crystal Structure Communications, 1998The title compound crystallizes as a hydrated zwitterion with the site for the water molecule only partially occupied [site-occupancy factor 0.28 (1)] and a formula of C10H12N2O3.0.28H2O. The hydroxyl H atom forms an intramolecular hydrogen bond to the imine N atom. The NH3+ and COO− groups of the zwitterion form a two-dimensional hydrogen-bond network
M. A. Whitener +2 more
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4-Hydroxybenzoic acid—a versatile platform intermediate for value-added compounds
Applied Microbiology and Biotechnology, 20184-Hydroxybenzoic acid (4-HBA) has recently emerged as a promising intermediate for several value-added bioproducts with potential biotechnological applications in food, cosmetics, pharmacy, fungicides, etc. Over the past years, a variety of biosynthetic techniques have been developed for producing the 4-HBA and 4-HBA-based products.
Songwei, Wang +4 more
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Synthesis of thermotropic polybenzoxazole using 3-amino-4-hydroxybenzoic acid
Journal of Polymer Research, 2017Bio-based polybenzoxazoles (PBOs) are prepared by polycondensation of diacid monomer derived from 3-amino-4-hydroxybenzoic acid with a series of aliphatic diamines. Resulting bio-based PBOs have high weight average molecular weight ranging 5.70–7.20 × 104 g/mol and show ultrahigh thermal resistance with T 10
Mohammad Asif Ali +4 more
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