TY - JOUR
T1 - A self-healing system based on ester crosslinks for carbon black-filled rubber compounds
AU - Algaily, Bashir
AU - Kaewsakul, Wisut
AU - Sarkawi, Siti Salina
AU - Kalkornsurapranee, Ekwipoo
N1 - Funding Information:
Funding: This research was funded by the Higher Education Research Promotion and Thailand’s Education Hub for the Southern Region of the ASEAN Countries Project Office of the Higher Education Commission, as well as by the Natural Rubber Innovation Research Institute (Grant No. SCI6201170s), Prince of Songkla University.
Funding Information:
This research was funded by the Higher Education Research Promotion and Thailand?s Education Hub for the Southern Region of the ASEAN Countries Project Office of the Higher Education Commission, as well as by the Natural Rubber Innovation Research Institute (Grant No. SCI6201170s), Prince of Songkla University.
Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021/3/4
Y1 - 2021/3/4
N2 - Carbon black-reinforced rubber compounds based on the blends of natural rubber (NR) and butadiene rubber (BR) for tire sidewall applications were formulated to investigate the self-healing efficacy of a modifier called EMZ. This modifier is based on epoxidized natural rubber (ENR) modified with hydrolyzed maleic anhydride (HMA) as the ester crosslinking agent plus zinc acetate dihydrate (ZAD) as the transesterification catalyst. The influence of EMZ modifier content in sidewall compounds on processing characteristics, reinforcement, mechanical and fatigue properties, as well as property retentions, was investigated. Increasing the content of EMZ, the dump temperatures and Mooney viscosities of the compounds slightly increase, attributed to the presence of extra polymer networks and filler–rubber interactions. The bound rubber content and Payne effect show a good correction that essentially supports that the EMZ modifier gives enhanced filler–rubber interaction and reduced filler–filler interaction, reflecting the improved homogeneity of the composites. This is the key contribution to a better flex cracking resistance and a high fatigue-to-failure resistance when utilizing the EMZ modifier. To validate the property retentions, molecular damages were introduced to vulcanizates using a tensile stress–strain cyclic test following the Mullins effect concept. The property retentions are significantly enhanced with increasing EMZ content because the EMZ self-healing modifier provides reversible or dynamic ester linkages that potentially enable a bond-interchange mechanism of the crosslinks, leading to the intermolecular reparation of the rubber network.
AB - Carbon black-reinforced rubber compounds based on the blends of natural rubber (NR) and butadiene rubber (BR) for tire sidewall applications were formulated to investigate the self-healing efficacy of a modifier called EMZ. This modifier is based on epoxidized natural rubber (ENR) modified with hydrolyzed maleic anhydride (HMA) as the ester crosslinking agent plus zinc acetate dihydrate (ZAD) as the transesterification catalyst. The influence of EMZ modifier content in sidewall compounds on processing characteristics, reinforcement, mechanical and fatigue properties, as well as property retentions, was investigated. Increasing the content of EMZ, the dump temperatures and Mooney viscosities of the compounds slightly increase, attributed to the presence of extra polymer networks and filler–rubber interactions. The bound rubber content and Payne effect show a good correction that essentially supports that the EMZ modifier gives enhanced filler–rubber interaction and reduced filler–filler interaction, reflecting the improved homogeneity of the composites. This is the key contribution to a better flex cracking resistance and a high fatigue-to-failure resistance when utilizing the EMZ modifier. To validate the property retentions, molecular damages were introduced to vulcanizates using a tensile stress–strain cyclic test following the Mullins effect concept. The property retentions are significantly enhanced with increasing EMZ content because the EMZ self-healing modifier provides reversible or dynamic ester linkages that potentially enable a bond-interchange mechanism of the crosslinks, leading to the intermolecular reparation of the rubber network.
KW - Composite
KW - Crosslink
KW - Polymer failure
KW - Self-reparation
KW - Sidewall compound
KW - UT-Gold-D
UR - http://www.scopus.com/inward/record.url?scp=85104635804&partnerID=8YFLogxK
U2 - 10.3390/jcs5030070
DO - 10.3390/jcs5030070
M3 - Article
AN - SCOPUS:85104635804
SN - 2504-477X
VL - 5
JO - Journal of Composites Science
JF - Journal of Composites Science
IS - 3
M1 - 70
ER -