کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5206252 1502955 2014 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Material behaviourEffect of MWCNTs and graphene on the crystallization of polyurethane based nanocomposites, analyzed via calorimetry, rheology and AFM microscopy
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Material behaviourEffect of MWCNTs and graphene on the crystallization of polyurethane based nanocomposites, analyzed via calorimetry, rheology and AFM microscopy
چکیده انگلیسی

Isothermal crystallization of two nanocomposites composed of multiwalled carbon nanotubes (MWCNT) and graphene dispersed in a hot melt adhesive polyurethane (PUR) is investigated. Rheological percolation is reached for PUR/MWCNT, but not for PUR/Graphene nanocomposites. Analysis of the elastic modulus versus time indicates that the crystallization process is more hastened by MWCNTs than by graphene, favouring the welding process of the corresponding adhesives. Correlative AFM images show that the crystal size follows the order: Crystals in neat PUR > Crystals in PUR/Graphene > Crystals in PUR/MWCNT. The nucleation density is higher in the case of MWCNTs due to the poorer dispersion of graphene in the PUR matrix. Analysis of DSC results by the Avrami equation and the fitting of G′-time results to a rheological equation adapted from the Avrami equation, show that the parameter n decreases from n = 3 for neat PUR to n = 2 for both nanocomposites. The coherence between the value n = 2 and AFM images is demonstrated: The lamellae organization in two dimensional growth, that brings about nucleated axialites, as expected for n = 2, is confirmed by AFM microscopy.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer Testing - Volume 35, May 2014, Pages 101-108
نویسندگان
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