Dynamic mechanical and Charlesby-Pinner analyses of radiation cross-linked ethylene-vinyl acetate copolymer (EVA)

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F70883521%3A28110%2F25%3A63595339" target="_blank" >RIV/70883521:28110/25:63595339 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.mdpi.com/1420-3049/30/7/1485" target="_blank" >https://www.mdpi.com/1420-3049/30/7/1485</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/molecules30071485" target="_blank" >10.3390/molecules30071485</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Dynamic mechanical and Charlesby-Pinner analyses of radiation cross-linked ethylene-vinyl acetate copolymer (EVA)

Popis výsledku v původním jazyce

The properties of EVA copolymers with various vinyl acetate (VA) contents were compared, with EVA 206 (6 wt.% VA) and EVA 212 (12 wt.% VA) having the same melt flow indices of 2 g/10 min. The impact of electron irradiation at levels of 60, 120, and 180 kGy was studied. Four testing methods were employed as follows: wide-angle X-ray diffraction (WAXD); differential scanning calorimetry (DSC); dynamic mechanical analysis (DMA), using a high-temperature frequency sweep at 150 °C; and gel content analysis. The amount of crystalline phase was determined by WAXD and DSC. Copolymers with a higher VA content (EVA 212) had lower crystallinity. The increase in the amorphous phase allows for the greater movement of radicals, enabling them to react and form cross-links. The effects of the VA content, radiation dose, and frequency on dynamic mechanical properties were investigated by DMA. The DMA analysis focused on the shear storage modulus (Formula presented.), damping factor (Formula presented.), and complex viscosity (Formula presented.). After irradiation, the damping factor (Formula presented.) decreased with an increasing VA content, indicating improved elasticity and a higher degree of cross-linking. A gel content analysis was used to calculate the parameters of the Charlesby-Pinner and Charlesby–Rosiak equations, which help with the determination of the relationship between cross-linking and chain scission. The ratio of cross-linking to scission (Formula presented.) was higher for the EVA with a higher VA content (EVA 212). Due to a higher VA content (12 wt.%), EVA 212 exhibits more efficient network formation.

Název v anglickém jazyce

Dynamic mechanical and Charlesby-Pinner analyses of radiation cross-linked ethylene-vinyl acetate copolymer (EVA)

Popis výsledku anglicky

The properties of EVA copolymers with various vinyl acetate (VA) contents were compared, with EVA 206 (6 wt.% VA) and EVA 212 (12 wt.% VA) having the same melt flow indices of 2 g/10 min. The impact of electron irradiation at levels of 60, 120, and 180 kGy was studied. Four testing methods were employed as follows: wide-angle X-ray diffraction (WAXD); differential scanning calorimetry (DSC); dynamic mechanical analysis (DMA), using a high-temperature frequency sweep at 150 °C; and gel content analysis. The amount of crystalline phase was determined by WAXD and DSC. Copolymers with a higher VA content (EVA 212) had lower crystallinity. The increase in the amorphous phase allows for the greater movement of radicals, enabling them to react and form cross-links. The effects of the VA content, radiation dose, and frequency on dynamic mechanical properties were investigated by DMA. The DMA analysis focused on the shear storage modulus (Formula presented.), damping factor (Formula presented.), and complex viscosity (Formula presented.). After irradiation, the damping factor (Formula presented.) decreased with an increasing VA content, indicating improved elasticity and a higher degree of cross-linking. A gel content analysis was used to calculate the parameters of the Charlesby-Pinner and Charlesby–Rosiak equations, which help with the determination of the relationship between cross-linking and chain scission. The ratio of cross-linking to scission (Formula presented.) was higher for the EVA with a higher VA content (EVA 212). Due to a higher VA content (12 wt.%), EVA 212 exhibits more efficient network formation.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10404 - Polymer science

Projekt

—

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2025

Kód důvěrnosti údajů

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

Název periodika

Molecules

ISSN

1420-3049

e-ISSN

—

Svazek periodika

30

Číslo periodika v rámci svazku

7

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

24

Strana od-do

nestránkováno

Kód UT WoS článku

001463975200001

EID výsledku v databázi Scopus

2-s2.0-105002399038