Morphological analysis of highly filled propylene/ethylene copolymers

Abstract

A series of particulate composites based on a new family of propylene/ethylene (P/E) copolymers produced by Dow Chemical Co. were studied with microscopy and differential scanning calorimetry (DSC). To understand the good processability exhibited by the composites, we studied the composite microstructure and the bulk rheological properties. Here we report the results of a study of the microstructure and thermal behavior. Electron micrographs of the composites showed a uniform dispersion of the particles in the copolymer matrices at all experimental concentrations with very little particle agglomeration. The images suggested low adhesion between the matrices and the particles. The copolymers were semicrystalline, and their morphologies changed with the ethylene content. An increase in the ethylene content led to a decrease in the crystallinity and changes in the shape and size of the crystallites. Tapping-mode atomic force microcopy images of a 9 wt % ethylene copolymer contained spherulites, lamellae, and a crosshatched structure characteristic of a-isotactic polypropylene. The crosshatched structure was not present at higher ethylene contents. A DSC study of the pure copolymers and their composites revealed that only very small modifications to the thermal behavior of the P/E copolymers were induced by calcium carbonate particles.

Investigation of cell–substrate interactions by focused ion beam preparation and scanning electron microscopy

“…Although the FIB technology is widely used in the semiconductor industry, its usability for the preparation of polymer solid interfaces or cross-sectioning of adherent cells on scaffolds is still underestimated. [9,10] Resulting from the limited availability of the FIB technology so far, only a few studies about FIB processing of such materials are known. In polymer material science, FIB preparations are used for surface nanostructuring [9,[11][12][13] as well as to investigate aging effects of polymer components.…”

“…[14] The use of FIB for the preparation of polymeric samples is delicate, because it can induce amorphization of the sample surface, scission and/or cross-linking of polymer chains, shrinkage of the chains, and modification of the surface chemistry. [9,10,15] To suppress such damaging effects of the ion beam on polymers and biological specimens, a well defined set of processing parameters has to be considered. [16,17] Furthermore, there are only few studies of FIB preparation techniques in the field of tissue engineering.…”

Cryo‐FIB‐Preparation and Cryo‐SEM Investigation of Gold Nanolayers Used as Absorber for Laser Welding of Polymer Foils

“…Although the FIB technology is widely used in the semiconductor industry, the preparation of polymer solid interfaces is still at the beginning. [6,7] Resulting from the previously limited availability of the FIB technology, only a few studies about FIB preparation are known. In polymer material science FIB preparations are used for nanostructuring polymeric surfaces [8,9,10,11] as well as to investigate aging effects of polymer components.…”