Janusz Kozakiewicz - Academia.edu (original) (raw)

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University Of Veterinary And Animal Sciences Lahore

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Papers by Janusz Kozakiewicz

Possibilites d'utilisation de melanges de polyurethanne et d'adducts isocyanate/asphalte ... more Possibilites d'utilisation de melanges de polyurethanne et d'adducts isocyanate/asphalte dissous dans des hydrocarbures comme peintures anticorrosion

Molecules, 2022

The cationic emulsion polymerization of octamethylcyclotetrasiloxane (D4) in mixtures with methyl... more The cationic emulsion polymerization of octamethylcyclotetrasiloxane (D4) in mixtures with methyltriethoxysilane (MTES) and vinyltriethoxysilane (VTES) was studied by FTIR ATR, GC, the development of a toluene insoluble fraction of the polymer and a gravimetric analysis. The polymerization of D4 alone was also conducted for comparison and, additionally, the development of molecular weight of polydimethylsiloxane (PDMS) obtained in that process was studied by GPC. Dodecylbenzenesulphonic acid (DBSA) was used as a surfactant and catalyst. The process was carried out in a “starved feed” mode by adding dropwise the monomer mixture to the aqueous solution of DBSA. FTIR ATR spectra were recorded by the sensor placed in the probe tip of a ReactIR 15TM apparatus. It was found that the silicone polymer formation proceeded faster when D4 was polymerized in the mixture with alkoxysilanes, especially in the beginning of the process, and that already at the beginning of the process, the partly c...

Ces systemes sont tres thixotropes. Ils donnent des revetements presentant de bonnes proprietes m... more Ces systemes sont tres thixotropes. Ils donnent des revetements presentant de bonnes proprietes mecaniques et anticorrosives

PVC nanocomposites containing 0.5 wt. %/VCM of either nanosilica or hybrid core/shell type nanofi... more PVC nanocomposites containing 0.5 wt. %/VCM of either nanosilica or hybrid core/shell type nanofiller were produced in-situ in suspension polymerisation and rigid films were prepared. The composites obtained were applied in the blends for rigid films. The properties of them were checked and showed advantageous differences in tear resistance and tensile impact properties. It appeared the composites properties let reduce the amount of impact modifiers in the blends at least 40 %. The PVC/SiO2 composite shows the best properties. Even for the blend containing 0.7 part of standard amount of impact modifier (suitable for this formulation) all the properties (except tensile impact strength crosswise) are significantly better than those of PVC blend with full amount of impact modifier.

Desalination, 2004

Aqueous dispersions of siloxane-urethane copolymers (polysiloxaneurethanes) containing 049% of s... more Aqueous dispersions of siloxane-urethane copolymers (polysiloxaneurethanes) containing 049% of siloxane moieties were synthesized by the modified prepolymer-ionomer method. The properties of the dispersions were determined. Dense membranes were prepared ...

Journal of Membrane Science, 2006

... The main objective of the present study is to analyse the viability of using poly ... indicat... more ... The main objective of the present study is to analyse the viability of using poly ... indicating phase separation of soft and hard segments and a domain morphology of the ... Mixed gas permeationproperties of membranes were determined with a feed containing 2 vol.% n-butane and ...

Aqueous silicone-acrylic dispersions of hybrid core-shell particle structure can be obtained in t... more Aqueous silicone-acrylic dispersions of hybrid core-shell particle structure can be obtained in the process of emulsion polymerization of acrylic or methacrylic monomers in previously synthesized silicone resin dispersions. If the Tg of the acrylic (methacrylic) shell is around 120 oC or higher, drying of such dispersions leads to “nanopowders” which can be applied as impact modifiers for plastics and powder coatings due to the presence of low Tg silicone resin contained in the hybrid nanoparticles. The aim of our study was to investigate the effect of silicone resin composition on the properties of dispersions and the corresponding nanopowders what, in turn, was expected to influence the properties of powder coatings modified with such nanopowders.

Polimery

Polymerization of vinyl chloride in the presence of nanofillerseffects on the shape and morpholog... more Polymerization of vinyl chloride in the presence of nanofillerseffects on the shape and morphology of PVC grains Summary-Suspension polymerization of vinyl chloride has been carried out in the presence of various types of nanofillers chosen from clays, silica (pure or functionalized), silicone polymer or hybrid core/shell ones. Nanofillers used in VC polymerization significantly influence the structure and shape of PVC grain: from typical one in case of control sample and in the presence of silica to "cake-like" in case of functionalized silica, "sea-shells" with silicone polymer use or "balls" and "dented balls"-not typical for suspension PVC-in the presence of hybrid core/shell particles. The last ones look just as emulsion PVC although were prepared in suspension polymerization process. It has been found, using SEM and TEM methods, that distribution of nanofiller in polymer was rather uniform. MMT is semiintercalated/semiexfoliated in PVC grain. Some regions showing mesoporosity were also found (especially in the presence of silica) suggesting the formation of more ordered structures in the grain. We can foresee that not only the presence and distribution of nanofillers in PVC grain but also the change of PVC grain shape caused by them can both influence the final properties of PVC and its processability.