TY - JOUR

T1 - Kinetics of the Glass Transition of Silica-Filled Styrene–Butadiene Rubber

T2 - The Effect of Resins

AU - Lindemann, Niclas

AU - Schawe, Jürgen E.K.

AU - Lacayo-Pineda, Jorge

N1 - Funding Information: Funding: This research received funding from the European Union’s Horizon 2020 research and innovation program, grant number 760907. The APC was funded by the Open Access Publishing Fund of Leibniz Universität, Hannover.

PY - 2022/7/1

Y1 - 2022/7/1

N2 - Resins are important for enhancing both the processability and performance of rubber. Their efficient utilization requires knowledge about their influence on the dynamic glass transition and their miscibility behavior in the specific rubber compound. The resins investigated, poly-(α-methylstyrene) (AMS) and indene-coumarone (IC), differ in molecular rigidity but have a similar aromaticity degree and glass transition temperature. Transmission electron microscopy (TEM) investigations show an accumulation of IC around the silanized silica in styrene–butadiene rubber (SBR) at high contents, while AMS does not show this effect. This higher affinity between IC and the silica surface leads to an increased compactness of the filler network, as determined by dynamic mechanical analysis (DMA). The influence of the resin content on the glass transition of the rubber compounds is evaluated in the sense of the Gordon–Taylor equation and suggests a rigid amorphous fraction for the accumulated IC. Broadband dielectric spectroscopy (BDS) and fast differential scanning calorimetry (FDSC) are applied for the characterization of the dielectric and thermal relaxations as well as for the corresponding vitrification kinetics. The cooling rate dependence of the vitrification process is combined with the thermal and dielectric relaxation time by one single Vogel–Fulcher–Tammann–Hesse equation, showing an increased fragility of the rubber containing AMS.

AB - Resins are important for enhancing both the processability and performance of rubber. Their efficient utilization requires knowledge about their influence on the dynamic glass transition and their miscibility behavior in the specific rubber compound. The resins investigated, poly-(α-methylstyrene) (AMS) and indene-coumarone (IC), differ in molecular rigidity but have a similar aromaticity degree and glass transition temperature. Transmission electron microscopy (TEM) investigations show an accumulation of IC around the silanized silica in styrene–butadiene rubber (SBR) at high contents, while AMS does not show this effect. This higher affinity between IC and the silica surface leads to an increased compactness of the filler network, as determined by dynamic mechanical analysis (DMA). The influence of the resin content on the glass transition of the rubber compounds is evaluated in the sense of the Gordon–Taylor equation and suggests a rigid amorphous fraction for the accumulated IC. Broadband dielectric spectroscopy (BDS) and fast differential scanning calorimetry (FDSC) are applied for the characterization of the dielectric and thermal relaxations as well as for the corresponding vitrification kinetics. The cooling rate dependence of the vitrification process is combined with the thermal and dielectric relaxation time by one single Vogel–Fulcher–Tammann–Hesse equation, showing an increased fragility of the rubber containing AMS.

KW - BDS

KW - FDSC

KW - glass transition

KW - kinetics

KW - resin

KW - rubber

UR - http://www.scopus.com/inward/record.url?scp=85133441188&partnerID=8YFLogxK

U2 - 10.3390/polym14132626

DO - 10.3390/polym14132626

M3 - Article

AN - SCOPUS:85133441188

VL - 14

JO - Polymers

JF - Polymers

SN - 2073-4360

IS - 13

M1 - 2626

ER -