polypropylene

Polypropylene/Organophilic clay Nanocomposites Using Metallocene Catalysts through in situ Polymerization

The organophilic clays employed for the preparation of supported metallocene catalysts Viscogel B8, Claytone HY and Cloisite 15A were evaluated in propylene polymerization. These supports were chemically pre-treated with trimethylaluminium (TMA). The organoclays, as well as the prepared metallocene catalysts, were analyzed by X-ray diffractometry (XRD).

Influence of the Preparation Technique of MgCl2/TiCl4 Ziegler-Natta Catalyst on the Performance in Ethylene and Propylene Polymerization

Different methods to remove the alcohol of adduct MgCl2nEtOH were studied to obtain Ziegler-Natta catalysts for evaluation in ethylene and propylene polymerization. Thus, the adduct MgCl2nEtOH was submitted to thermal dealcoholation, as well as chemical dealcoholation with different substances: titanium tetrachloride, triethylaluminum, and dichloro-dimethylsilane. Thermogravimetric analyses (TGA) were performed to obtain information on the thermal characteristics of adducts and prepared supported catalysts.

Composites on the Basis of Discrete Woven Filler and Polypropylene

Possibility of fabrication by the method of extrusion of composite on the basis of polypropylene and discrete filler in the form of the grinded fabric is studied. Influence on physical-mechanical properties and water absorption of obtained materials for the fillers of various chemical nature - fabrics on the basis of synthetic or/and natural fibers, their filling degree in polypropylene, as well as dependences of these properties on pre-award dressing of filler is estimated.

Technological Aspect of Influence of Long-Term Constructional Properties under Compression of Thermoplastic Polymer Composites

Feasibility of complex research of technological aspects and long-term structural properties of the thermoplastic polymer composite that allowed to define a perspective direction to improve the practical appeal and, accordingly, provided the requirements thoroughly to search the fibrous filler of polymeric nature with predictable provision roughness to the surface relief are provided.

The Effect of Cooling Rate during Crystallization on the Melting Behavior of Polypropylenes of Different Chemical Structure

The melting behavior of polypropylenes of different chemical structure (isotactic homopolypropylene, propylene-based block and random copolymers and maleic anhydride grafted polypropylene) was studied by differential scanning calorimeter (DSC) and optical microscopy. Melting behavior and the crystal structure of polypropylene and its copolymers were observed depending on the crystallization rate, chemical nature of co-monomer unites and regularity of co-monomer units arrangement in the polypropylene main chain.