Effect of temperature, duration and speed of pre-mixing on the dispersion of clay/epoxy nanocomposites

Abstract

The effect of temperature, duration and speed of pre-mixing on the dispersion of organoclay in epoxy was studied. The technique of high-speed mixing process was used. Epoxy and Cloisite 30B were pre-mixed at different temperatures, different speeds and for different durations of time. The quality of dispersion and intercalation/exfoliation of organoclay in epoxy after pre-mixing (before adding hardener) was analyzed by means of X-ray diffraction (XRD) and viscosity measurement. The dispersion and intercalation/exfoliation of organoclay in the epoxy nanocomposites (ENCs) after curing were characterized by XRD, field emission gun scanning electron microscopy (FEGSEM) and TEM. The results illustrate that the clay particles were broken down to smaller and smaller sizes with increase of pre-mixing temperature and especially with increase in pre-mixing speed. These parameters do not significantly affect the intercalation/exfoliation of organoclay in epoxy at the pre-mixing step, but they have indirect effect on intercalation/exfoliation at the curing step.

The Effect of Bi-Functionalized MMT on Morphology, Thermal Stability, Dynamic Mechanical, and Tensile Properties of Epoxy/Organoclay Nanocomposites

“…In order to achieve the desired properties of epoxy-clay nanocomposites, it is important to understand the role of the surface modifier and how the interfacial interaction occurs. Besides that, mixing parameters such as mixing speed, mixing duration, and temperature do play an important role in the formation of the final structure/configuration (conventional, intercalated, or exfoliated) of epoxy-clay nanocomposites [18].In recent years, utilizing a bi-functionalized nanoclay in preparation of PNCs is gaining more interest from the research community. Shakeri et al [19] reported on a modification of organoclay with 3-trimethoxysilylpropyl methacrylate (MPS) as a reactive silane coupling agent to prepare a polymethylmethacrylate (PMMA)/OMMT nanocomposite.…”

“…In order to achieve the desired properties of epoxy-clay nanocomposites, it is important to understand the role of the surface modifier and how the interfacial interaction occurs. Besides that, mixing parameters such as mixing speed, mixing duration, and temperature do play an important role in the formation of the final structure/configuration (conventional, intercalated, or exfoliated) of epoxy-clay nanocomposites [18].…”

The impact of ultra-low amounts of amino-modified MMT on dynamics and properties of densely cross-linked cyanate ester resins

“…and chemical (chemical structure and reactivity of the components, affinity, etc.) nature [10][11][12][13][14]. Since the surfaces of virgin layered silicates are hydrophilic, significant hindrances appear at synthesis of high-performance polymer/clay nanocomposites comprising hydrophobic polymer matrices.…”

Studies of anhydride-cured epoxy networks with bonded and unbonded polyhedral oligomeric silsesquioxane (POSS)

“…how well the dispersion of clay is in epoxies. Recently, Ngo et al have studied the effect of temperature, duration and speed of pre-mixing on the dispersion of Cloisite 30B clay in DGEBA epoxy [115]. Their findings show that pre-mixing at higher speed and temperatures improved the intercalation/exfoliation of clay during cure.…”

“…For POSS-MMT, the POSS-imidazolium cations were incorporated into clay using the cationic exchange procedure before mixing with the epoxy. The mixture was premixed under high-speed mechanical shear for an extended period to allow diffusion of epoxy molecules into the clay galleries [115]. The pre-mixing stage was monitored with POSS-imidazolium modified clay/epoxy systems POM at selected intervals and the consequential micrographs suggest marked improvement in dispersion with prolonged mixing time and the clay was broken down into smaller particles gradually (Fig.…”