Modification of polyamide 6 with halloysite nanotubes

This article investigates the effect of modifying the polypropylene (iPP) a-phase nucleating agent 1,3:2,4-bis(3,4-dimethylbenzylidene) sorbitol (DMDBS) with tetrasilanolphenyl silsesquioxane (phPOSS). It has been proven that an increasing amount of silsesquioxane leads to differences in the crystallization behavior. What is more, it has been observed that the nucleation effect that results from the addition of sorbitol derivatives is suppressed by phPOSS activity. To understand the influence of phPOSS addition on the crystallization kinetics of PP/DMDBS/phPOSS composites that have been prepared by melt processing in a twin screw extruder, differential scanning calorimetry, rotational rheometry and Fourier transform infrared spectroscopy are performed.

“…The Avrami theory that was modified by Jeziorny has been used to analyze nonisothermal crystallization kinetics . The Avrami equation was used in the following form:

1 - X_{t} = \exp (- Z_{t} t^{n})

where Z t is the Avrami constant rate, n is the Avrami exponent and X t is the relative crystallinity at temperature T , which can be defined by

X_{t} = \frac{\int_{0}^{t} (d H (t) / d t) d t}{\int_{0}^{\infty} (d H (t) / d t) d t}

where (d H (t)/d t ) is the heat flow and X t ( t ) and X t (∞) indicate the absolute crystallinity at time t and at the end of the crystallization process.…”

Section: Methodsmentioning

confidence: 99%

Influence of a sorbitol‐based nucleating agent modified with silsesquioxanes on the non‐isothermal crystallization of isotactic polypropylene

Barczewski

Dobrzyńska‐Mizera

Dudziec

et al. 2013

“…New inorganic–organic modifiers and nano modifiers have recently been gaining ground among scientists as the main focus of scientific research . The polyhedral oligomeric silsesquioxanes (POSS) which are new hybrid compounds, made of cube‐octameric frameworks with inorganic silica like core and surrounded by eight organic corner groups, are one of the representatives of this group .…”

Section: Introductionmentioning

confidence: 99%

Epoxy compositions cured with aluminosilsesquioxanes: Thermomechanical properties

Chmielewska

Sterzyński

Dudziec

2014

The aim of this study was to verify the influence of bis(heptaphenylaluminosilsesquioxane) (AlPOSS), used as a curing agent, on the thermomechanical properties of epoxy resin. Moreover, various curing conditions were taken into account. Epoxy casts were prepared from epoxy resin based on bisphenol A cured with different amounts of bis(heptaphenylaluminosilsesquioxane). The thermomechanical properties were investigated during dynamical mechanical thermal analysis (DMTA) in two cycles of heating. The storage modulus G 0 of the epoxy casts was found to be higher in comparison to the reference epoxy sample and significantly dependent on the POSS content. A correlation between the glass transition temperatures (T g ), the curing conditions and the amount of curing agents were closely related. The occurrence of the crosslinking process in epoxy matrix was proved by the FTIR spectroscopy. The structure of the epoxy casts was investigated using scanning electron microscopy (SEM). V C 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40672.

“…The polymer composite belongs to the group of most popular manufactured materials, with still expanding application areas. In recent years there has been rapid development in the research areas of polymer nanocomposites, biocomposites, and the technologies of processing such a materials . The biocomposites research found widespread industry applications, unfortunately the utility of the nanoscale fillers research results does not allow for the use of these technologies on an industrial scale .…”

Section: Introductionmentioning

confidence: 99%

Fabrication of the self‐reinforced composites using co‐extrusion technique

Andrzejewski

Szostak

Barczewski

et al. 2014

The results of this work relate to the use of co‐extrusion technology in the preparation of monocomposite pellets. The low‐melting polypropylene copolymer was used as a matrix material. The high strength polypropylene fibers were used as a fibrous reinforcement. Research confirms the possibility to produce the pellets with fibrous structure. The prepared composite material in the form of pellets was processed and shaped using the injection molding technology. Obtained samples were subjected to mechanical testing in the static tensile test and dynamic mechanical analysis. Research complements microscopic observation of scanning electron microscopy. The measurement results confirm the reinforcing effect of the fibers. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41180.