A coarse-grained model has been built to study the effect of the interfacial
interaction between spherical filler particles and polymer on the mechanical properties of
polymer nanocomposites. The polymer is modeled as bead-spring chains, and nano-fillers
grafted with coupling agent are embedded into the polymer matrix. The potential parameters
for polymer and filler are optimized to maximally match styrene-butadiene rubber reinforced
with silica particles. The results indicated that, to play a noticeable role in mechanical
reinforcement, a critical value exists for the grafting density of the filler–polymer coupling
agent. After reaching the critical value, the increase of grafting density can substantially
enhance mechanical properties. It is also observed that the increase of grafting density does not
necessarily increase the amount of independent polymer chains connected to fillers. Instead, a
significant amount of increased grafting sites serve to further strengthen already connected
polymer and filler, indicating that mechanical reinforcement can occur through the locally
strengthened confinement at the filler–polymer interface. These understandings based on
microstructure visualization shed light on the development of new filler polymer interfaces
with better mechanical properties.
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This content will become publicly available on July 22, 2024
A novel strategy to functionalize styrene butadiene rubber toward enhanced interfacial interaction with silica
Incorporation of nanofillers (such as silica) into elastomer matrix is the most common strategy to prepare high‐performance rubber products. However, the poor dispersion of nanofillers in non‐affinity rubber materials and the weak interfacial interaction significantly limit the processing and mechanical properties. To reduce the polarity difference and enhance the interfacial interaction between silica and styrene butadiene rubber (SBR), we prepared a hydroxyethyl acrylate‐grafted SBR (SBR‐g‐HEA) through the redox initiator system, and subsequently fabricated SBR‐g‐HEA/silica nanocomposites by simple mechanical blending. The effects of reaction conditions on the grafting rate were studied in detail. ATR‐FTIR and1H‐NMR collectively confirmed the successful grafting of HEA groups on SBR molecular chains, and the grafting fraction could be regulated from 0% to 2.5%. Scanning electron microscope (SEM) and rubber processing analyzer (RPA) showed that the incorporation of HEA could significantly improve the dispersion of silica nanoparticles in SBR matrix. Notably, the resulting SBR‐g‐HEA exhibited significantly enhanced attributes when compared to their unmodified counterparts, including superior mechanical properties, improved wear resistance, and reduced heat generation. The strategy proposed here provided insights toward the fabrication of non‐affinity rubber/filler nanocomposites for high‐performance rubber products and green tire.
more » « less- NSF-PAR ID:
- 10458680
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Applied Polymer Science
- Volume:
- 140
- Issue:
- 39
- ISSN:
- 0021-8995
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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