In this paper the method of modification of polypropylene planar surfaces and microfibers through covalent grafting of a polyacrylic acid nanolayer by a free radical mechanismis presented.After grafting of the nanolayers, the hydrophobic surface of the polypropylene acquires hydrophilic properties. These changes are confirmed by the alteration of the free surface energy on the planar surfaces and by the increase of retentioned water by the microfibers before and after modification.
The influence of Ni-containing polymer-silicate filler on the technological properties of polypropylene is presented. It was found that the introduction of silicate fillers modified by polyvinyl alcohol change the flow patterns of polypropylene melts, in particular viscosity increases and anomalous viscosity shifts. The change of thermomechanical curves of polypropylene under the action of modified silicate fillers is shown.
The properties of the filled polymer compositions largely depend on the nature and surface properties of the fillers- basalt fiber. The possibility of modifying the surface of the basalt fiber with commercial polyhexamethyleneguanidinehydrochloride and non-commercial polydiethyleneaminoguanidine - appretes, were demonstrated for the first time.
The interrelation of physico-mechanical and technological characteristics of newly created nanocomposites on the basis of polypropylene (PP)/polyamide (PA-6) mixture with PVP-modified montmorillonite has been investigated. The significant impact of modified polyamide on technological, physical and mechanical properties and heat resistance of polypropylene has been determined. It has been established that the melt flow index of the resulting composites increases by more than 2 times, compared with pure PP.
Low-melting glass has been synthesized in the system PbO-ZnO-B2O3 and Na2O-P2O5-MoO3 and its composition has been developed. The effect of the glass chemical composition on the softening temperature and the change of appearance during the heating have been established. Polypropylene-based composite with different content of glass powder as a filler was obtained. Thermophysical properties of the composites were determined. Introduction of glass powder to the polypropylene composition damaged the material structure homogeneity.
Mixtures based on polypropylene (PP) and polyamide (PA) are of great importance as structural materials, the mixing of which reduces the negative characteristics of the original polymers. Non-polar PP significantly reduces water absorption of the material during mixing with polar high hydrophilic PA. As a result, the effect of moisture on the mechanical and thermal properties of the composites decreases. On the other hand, mixing PP with PA can extend the temperature range of material exploitation at negative temperatures.
The deformation properties of polypropylene modified by highly dispersed magnesium hydrosilicate are researched. It was established that the part of elastic deformation decreases with increasing of silicate filler content and the part of highly elastic and plastic deformation – increases. This fact indicates the formation of physically structured polymer composition material. Досліджено деформаційні властивості поліпропілену, модифікованого високодис- персним магнію гідросилікатом.
The essential effect of the nature and the content of the fine-grained modified polyvinylpyrrolidone magnesium hydrosilicate on the degree of crystallinity and crystallite sizes of polypropylene was established. This effect is caused by the change in the structural formations at the phases interface and by the nature of intermolecular interactions. Fine-grained particles of the modified magnesium hydrosilicate act as the additional centers of crystallization within the polymer composite material.
Досліджено вплив конструкційних особливостей одношнекового екструдера, а
саме довжини шнека і кількості канавок незмінного перерізу в зоні живлення
екструдера, та кількості і природи наповнювача на продуктивність екструдера під час
переробки композитів на основі поліпропілену, наповненого скловолокном, тальком,
крейдою. Встановлено, що використання екструдерів, які обладнані зоною живлення з
канавками, впливає на процес екструзії загалом, а також змінювати характеристики
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).