Search

ABSTRACT Electrically conductive polymer composites (CPCs) containing a carbonaceous filler and a polymeric matrix have been widely researched and utilized. Immiscible polymers are often used as the matrix of CPCs, which leads to segregated structures, hence low percolation threshold and good conductivity of a material. Polymeric blends often show low mechanical properties due to the lack of affinity of the resins. A way to improve toughness of a CPC and maintain good electrical properties is mixing two immiscible yet compatible resins. In our case one of them was polyethylene and the other was an olefinic conductive thermoplastic elastomer. In this study, a correlation between conductivity, mechanical properties, and morphology of conductive blends was analyzed. Results of tensile test, conductivity measurements, and differential scanning calorimetry were juxtaposed with information of phase morphology of the blends. A relationship of drastic changes of different properties of the blends and phase inversion point was found. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45512. [ABSTRACT FROM AUTHOR]

The poly(vinyl chloride) was modified by polyhedral oligomeric silsesquioxane with 3-chloropropyl groups (CP–POSS) by POSS concentration between 0.5 and 5 wt%. Two methods of POSS incorporation were applied, i.e. direct solid powders mixing or addition of POSS to PVC solution in THF. The final samples were produced by melt mixing in the Brabender mixer chamber. By means of the glass transition temperature (T g ) determination the influence of a low contain of CP–POSS on the effect of plasticization of the PVC compounds was investigated. Depending on the measurements method (dynamic mechanical analysis DMA and differential scanning calorimetry DSC) and on the DMA measurement frequency various values of the T g were observed. It was found that CP–POSS may act as a plasticizer, leading to certain lowering of the glass transition temperature of poly(vinyl chloride). [ABSTRACT FROM AUTHOR]

The results of this study are related to the implementation of the concept of self-reinforced composites. The input materials in preparation process were the bicomponent fibers. The studies were carried out on three types of fibers, HDPE/PP, cPP/PP, LPET/PET. In each case, the matrix material was a low melting polymer, and the core was made of a higher melting point polymer. The research was conducted for the materials shaped by an injection-molding technique. The analyses confirmed the two-component structure. Properties of the resulting composites confirmed the applicability of bicomponent fibers in the preparation of self-reinforced composites. [ABSTRACT FROM PUBLISHER]

ABSTRACT 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′ 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 ( Tg), 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). © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40672. [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of the study is to assess the effect of multi-walled carbon nanotubes (MWCNTs) on the wear behavior of MWCNT-doped epoxy resin. In this study, a laminating resin system designed to meet the standards for motor planes was modified with MWCNTs at mass fractions from 0.0 wt.% to 2.0 wt.%. The properties of the carbon nanotubes were determined in Raman spectroscopy and HR-TEM. An examination of wear behavior was conducted on a linear abraser with a visual inspection on an optical microscope and SEM imaging, mass loss measurement, and evaluation of the wear volume on a profilometer. Moreover, the mechanical properties of MWCNTs/epoxy nanocomposite were evaluated through a tensile test and Shore D hardness test. The study shows that the best wear resistance is achieved for the mass percentage between 0.25 wt.% and 0.5 wt.%. For the same range, the tensile strength reaches the highest values and the hardness the lowest values. Together with surface imaging and a topography analysis, this allowed describing the wear behavior in the friction node and the importance of the properties of the epoxy nanocomposite. [ABSTRACT FROM AUTHOR]