Browsing by Author "Glavchev I."

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    Application of the quantitative IR analysis of copolymers of trioxane
    (1997-01-01) Sirashki G.; Glavchev I.; Mateva R.
    The copolymers of trioxane and 5 to 50% phenyl-or n-butyl glycidyl ethers were investigated with elemental anlysis and IR spectroscopy. Using as an internal standard the methylene absorbance at 1470 sm-1 and the absorbance of C-O-C groups at 900, 930, 1100 and 1240 sm-1, it was determined that the absorbance at 1100 sm-1 is available for quantitative IR analysis of copolymers of trioxane and glycidyl ethers. © 1996 Elsevier Science Ltd.
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    Determination of the activity of phosphorus containing compounds on the crosslinking of epoxy resins by acid anhydrides
    (2002-02-09) Glavchev I.; Petrova K.; Devedjiev I.
    The crosslinking of epoxy resin by acid anhydrides was accelerated by several phosphorus containing compounds. The activity of the accelerators was evaluated by the rate of cure W and with activation energy Eact. Some of the accelerators were obtained by a new method and were new compounds. The activity of the accelerators was compared with their pKa values. The accelerators decreased the time and the temperature of crosslinking and the effect of chemical structure of acid anhydrides. © 2002 Elsevier Science Ltd. All rights reserved.
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    Determination of the coefficient of thermal expansion of epoxy composites
    (2002-01-01) Glavchev I.; Petrova K.; Ivanova M.
    Several compounds were used to design epoxy composites which would exhibit appropriate coefficients of thermal expansion (CTE): bisphenol A and diethyleneglycol based epoxy resins, seven different fillers and two hardeners. The CTE of these epoxy compositions with crystalline and amorphous filler was determined and its peak-like behavior as a function of temperature evaluated. © 2001 Elsevier Science Ltd. All rights reserved.
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    Determination of the coefficient of thermal expansion of epoxy composites
    (2002-01-01) Glavchev I.; Petrova K.; Ivanova M.
    Several compounds were used to design epoxy composites which would exhibit appropriate coefficients of thermal expansion (CTE): bisphenol A and diethyleneglycol based epoxy resins, seven different fillers and two hardeners. The CTE of these epoxy compositions with crystalline and amorphous filler was determined and its peak-like behavior as a function of temperature evaluated. © 2001 Elsevier Science Ltd. All rights reserved.
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    Determination of the coefficient of thermal expansion of epoxy composites
    (2002-01-01) Glavchev I.; Petrova K.; Ivanova M.
    Several compounds were used to design epoxy composites which would exhibit appropriate coefficients of thermal expansion (CTE): bisphenol A and diethyleneglycol based epoxy resins, seven different fillers and two hardeners. The CTE of these epoxy compositions with crystalline and amorphous filler was determined and its peak-like behavior as a function of temperature evaluated. © 2001 Elsevier Science Ltd. All rights reserved.