Processing polypropylene nanocomposites with silylated organoclays: Coupling at edges versus gallery faces

Weijie Ren, Amit K. Chaudhary, Krishnamurthy Jayaraman

Research output: Contribution to journalArticle

  • 2 Citations

Abstract

Polymer nanocomposites with layered silicates have two different types of interface sites: edges with hydroxyl groups and gallery faces with oxygen atoms. The polymer-particle interface at either site may be strengthened by silane coupling agents. The objective of this work was to investigate the morphology and rheology in the melt-compounded state and the reprocessed state of polypropylene-layered-silicate nanocomposites with reactive coupling by the silane and a long chain polymeric compatibilizer at different interface sites. Two different organically modified layered silicates with different aspect ratios and surfactants were treated with an aminoalkyldimethoxysilane; in one case, the silanols reacted only at the nanolayer edges while in the other case, the silanes entered the interlayer galleries. The effect of reactive coupling in both cases was noticeably improved dispersion with thinner stacks of nanolayers. The uniaxial extensional viscosity of these melts displayed greater strain hardening and more so in the case of reactive coupling at both faces and edges despite the aspect ratio of this organoclay being significantly lower. Upon reprocessing, while some degradation of the polymer matrix occurred in all cases, the effects on the nanostructure were quite different just as the effects on the rheology of the melts were quite different. These effects may be attributed to differing changes in the fraction of particle-attached polymer chains entangling with free polymer chains.

LanguageEnglish (US)
Pages4264-4273
Number of pages10
JournalIndustrial and Engineering Chemistry Research
Volume54
Issue number16
DOIs
StatePublished - Apr 29 2015

Profile

Organoclay
Polypropylenes
Silanes
Silicates
Nanocomposites
Polymers
Processing
Rheology
Aspect ratio
Compatibilizers
Coupling agents
Polymer matrix
Strain hardening
Surface-Active Agents
Hydroxyl Radical
Nanostructures
Surface active agents
Viscosity
Oxygen
Degradation

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Chemistry(all)
  • Industrial and Manufacturing Engineering

Cite this

Processing polypropylene nanocomposites with silylated organoclays : Coupling at edges versus gallery faces. / Ren, Weijie; Chaudhary, Amit K.; Jayaraman, Krishnamurthy.

In: Industrial and Engineering Chemistry Research, Vol. 54, No. 16, 29.04.2015, p. 4264-4273.

Research output: Contribution to journalArticle

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