Determination of activation energy of relaxation events in thermoplastic polyurethane by dynamic mechanical analysis

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F75081431%3A_____%2F18%3A00001259" target="_blank" >RIV/75081431:_____/18:00001259 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Determination of activation energy of relaxation events in thermoplastic polyurethane by dynamic mechanical analysis

Popis výsledku v původním jazyce

"In the present study, the activation energy associated with the primary and the secondary relaxation transition events in thermoplastic polyurethane has been determined using the multi-frequency dynamic mechanical analysis tests. The thermoplastic polyurethane under investigation was tested at temperatures between 145 K - 526 K, at frequencies of 0.5 Hz, 1 Hz, 2 Hz, 5 Hz and 10 Hz and at a constant heating rate of 3 K·min–1. It was observed that the studied materials show three relaxation events – glass transition of soft segments, glass transition of hard segments as well as secondary transition associated with short range order translation and with reorientational motions within the polyurethane crystals. The activation energies for all three observed relaxation events were determined from dynamic mechanical properties measured at various frequencies using a linearized Arrhenius equation. The calculated activation energy is 379.73 kJ·mol-1 for the glass transition of hard segments; for the secondary relaxation transition it is 65.53 kJ·mol-1 and for the glass transition of soft segments it is 45.98 kJ·mol-1."

Název v anglickém jazyce

Determination of activation energy of relaxation events in thermoplastic polyurethane by dynamic mechanical analysis

Popis výsledku anglicky

"In the present study, the activation energy associated with the primary and the secondary relaxation transition events in thermoplastic polyurethane has been determined using the multi-frequency dynamic mechanical analysis tests. The thermoplastic polyurethane under investigation was tested at temperatures between 145 K - 526 K, at frequencies of 0.5 Hz, 1 Hz, 2 Hz, 5 Hz and 10 Hz and at a constant heating rate of 3 K·min–1. It was observed that the studied materials show three relaxation events – glass transition of soft segments, glass transition of hard segments as well as secondary transition associated with short range order translation and with reorientational motions within the polyurethane crystals. The activation energies for all three observed relaxation events were determined from dynamic mechanical properties measured at various frequencies using a linearized Arrhenius equation. The calculated activation energy is 379.73 kJ·mol-1 for the glass transition of hard segments; for the secondary relaxation transition it is 65.53 kJ·mol-1 and for the glass transition of soft segments it is 45.98 kJ·mol-1."

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

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OECD FORD obor

20505 - Composites (including laminates, reinforced plastics, cermets, combined natural and synthetic fibre fabrics; filled composites)

Projekt

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Návaznosti

V - Vyzkumna aktivita podporovana z jinych verejnych zdroju

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Material Iwiss

ISSN

0933-5137

e-ISSN

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Svazek periodika

Neuveden

Číslo periodika v rámci svazku

48

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

8

Strana od-do

627-634

Kód UT WoS článku

000433499500013

EID výsledku v databázi Scopus

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