UserCom

Thermal Analysis UserCom 4

UserCom

UserComs Are Biannual Application Journals Intended for All Users of Thermal Analysis

Thermal Analysis UserCom 4
Thermal Analysis UserCom 4

Table of Contents:

TA Tip

  • Optimum utilization of the internal database

New in the sales program

  • The new STARe SW V4.0
  • The new TGA module TGA/SDTA851e

Applications

  • Determination of the eutectic composition of the system
  • Glass transition temperature of elastomers
  • PEI, glass transition by ADSC

Methyl-4-hydroxybenzoate/ p-hydroxybenzoic acid

Experimental aim

p-hydroxybenzoates are used as preserving agents and contain minor amounts of free 4-hydroxybenzoic acid as an impurity resulting from the synthesis with which they form a eutectic mixture. The example of the system methyl-4-hydroxybenzoate/ p-hydroxybenzoic acid will be used as an example to determine the composition of the eutectic.

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Experimental aim

The temperature of the glass transition (Tg) is suitable for the characterization, identification and quality monitoring of elastomers.

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Sample

Polyetherimide, PEI, Ultem 1000, injection molded part

Conditions

DSC Cell: DSC821 with sample changer and cryostat cooling Pan: Al standard 40 μl Sample preparation: 17.546 mg cut with knife in such a way that the bottom is flat DSC Measurement: Heating from 200 to 229 ° C at a mean rate of 1 K/min. Amplitude of sinusoidal oscillation 1 K, period 1 min

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