Krzysztof Karol Kowalczyk

Dr. Krzysztof Karol Kowalczyk

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Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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29 May 2021 in Polymers
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Łukasz ŁopusiewiczŁukasz Łopusiewicz
Łukasz Łopusiewicz
Magdalena ZdanowiczMagdalena Zdanowicz
Magdalena Zdanowicz
SMSzymon Macieja
Szymon Macieja
KKKrzysztof Karol Kowalczyk
Krzysztof Karol Kowalczyk
ABArtur Bartkowiak
Artur Bartkowiak
The preparation of biodegradable active packaging materials is still a major challenge. Here, we report the fabrication and characterization of poly(butylene succinate)-based (PBS) films enriched with a natural polyphenolic antioxidant—quercetin. The PBS-based films with various quercetin content (0.05; 0.10; 0.25 and 0.50 pph on PBS) were prepared via a solvent casting method. Physical (optical, mechanical, thermal, moisture and water sorption, water vapor and UV–vis barrier) and biofunctional (antioxidant and antibacterial against Escherichia coli and Staphylococcus aureus) film properties were tested. The migration of quercetin into model food liquid systems was determined. As a result of quercetin addition, significant changes in color, opacity and UV-blocking effect were observed. The presence of the active substance did not significantly affect the thermal properties of the PBS matrix. However, the mechanical properties of the films were slightly decreased. The films exhibited excellent free radicals (DPPH, ABTS, O2−) scavenging and some bactericidal activities. PBS-quercetin films with superior functional properties have many possibilities for active food packaging applications.

5 July 2013 in Polymer Engineering & Science
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GKGrzegorz Krala
Grzegorz Krala
AUAgnieszka Ubowska
Agnieszka Ubowska
KKKrzysztof Karol Kowalczyk
Krzysztof Karol Kowalczyk

1 December 2019 in Progress in Organic Coatings
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Journal Article
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BPBarbara Pilch-Pitera
Barbara Pilch-Pitera
DCDominika Czachor-Jadacka
Dominika Czachor-Jadacka
KKKrzysztof Karol Kowalczyk
Krzysztof Karol Kowalczyk
EPEwa Pavlova
Ewa Pavlova
JWJakub Wojturski
Jakub Wojturski
ŁBŁukasz Byczyński
Łukasz Byczyński

11 December 2019 in Polymers
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Agnieszka KowalczykAgnieszka Kowalczyk
Agnieszka Kowalczyk
KKKrzysztof Karol Kowalczyk
Krzysztof Karol Kowalczyk
KGKonrad Gziut
Konrad Gziut
New organic-inorganic hybrid copolymers (EA-POSSs) based on butyl acrylate, glycidyl methacylate, hydroxybutyl acrylate, acryloiloxybenzophenone and acryloxypropyl-heptaisobutyl-POSS (A-POSS) were prepared via free-radical solution polymerization (FRP) and applied as a component of thermally curable structural self-adhesive tapes (SATs). The EA-POSS with 0.25, 0.5 or 1 mol % of A-POSS exhibited significantly higher dynamic viscosity (ca. +104%), Mw (+61%) and polydispersity (+109%; measured using gel permeation chromatography) as well as lower Tg value (−16 °C) in relation to the A-POSS-free copolymer (EA-0). Differential scanning calorimetry (DSC) measurements (one glass transition process) confirmed statistic chain structure of the EA-POSS materials. Replacement of EA-0 by the EA-POSS copolymers in a SATs recipe caused simultaneous improvement of their self-adhesive features, i.e., adhesion (+70%), tack (+21%) and cohesion (+1590%). Moreover, the POSS-based copolymers improved the shear strength of thermally cured Al/SAT/Al overlap joints; the best mechanical resistance (before and after accelerated ageing tests) was observed for the sample containing 0.5 mol % of A-POSS (an increment range of 50–294% in relation to the A-POSS-free joints). Thermogravimetric analysis (TGA) revealed markedly improved thermal stability of the A-POSS-based SATs as well.

7 January 2021 in Polymers
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KGKonrad Gziut
Konrad Gziut
Agnieszka KowalczykAgnieszka Kowalczyk
Agnieszka Kowalczyk
BSBeataSchmidt Schmidt
BeataSchmidt Schmidt
KKKrzysztof Karol Kowalczyk
Krzysztof Karol Kowalczyk
MWMateusz Weisbrodt
Mateusz Weisbrodt
New modifiers (i.e., acrylic syrups; ASs) of epoxy-resin-based thermally curable structural self-adhesive tapes (SATs) were prepared via a free radical bulk polymerization (FRBP) of n-butyl acrylate, butyl methacrylate, glycidyl methacrylate, and hydroxybutyl acrylate. In the process, two kinds of UV-photoinitiators (i.e., monoacylphosphine oxide/Omnirad TPO and bisacylphosphine oxide/Omnirad 819) and various mixing speed of the monomers mixture (200–1000 rpm) were applied. The TPO-based syrups exhibited a lower copolymers content (10–24 wt%), dynamic viscosity (<0.1 Pa·s), molecular weights (Mn and Mw, and polydispersity (1.9–2.5) than these with Omnirad 819. Additionally, the higher mixing speed significantly reduced monomers conversion and viscosity of ASs as well as molecular weights of the acrylate copolymers. These parameters influenced the properties of thermally uncured (e.g., adhesion) and thermally cured SATs (shear strength of aluminum/SAT/aluminum overlap joints). Better self-adhesive features were observed for SATs-TPO (based on ASs with lower monomers conversion, Mn and Mw); however, a slightly higher shear strength was noted for the thermally cured SAT-819 (ASs with higher monomers conversion, Mn and Mw). An impact of polydispersity of the acrylate copolymers as well as crosslinking degree of thermally cured SATs on the mechanical strength was also revealed.

15 October 2021 in Polymers
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MWMateusz Weisbrodt
Mateusz Weisbrodt
Agnieszka KowalczykAgnieszka Kowalczyk
Agnieszka Kowalczyk
KKKrzysztof Karol Kowalczyk
Krzysztof Karol Kowalczyk
Thermally curable pressure-sensitive structural adhesives tapes (SATs) were compounded using a solid epoxy resin and multifunctional acrylic telomer solutions (MATs) prepared by a thermally initiated telomerization process in an epoxy diluent containing two kinds of telogens (CBr4 or CBrCl3). Dynamic viscosity, K-value, and volatile mater content in MATs (i.e., MAT-T with CBr4, MAT-B with CBrCl3) were investigated in relation to telogen type and content. The influence of MATs on the self-adhesive features and curing behavior of UV-crosslinked tapes as well as on the shear strength of thermally cured aluminum–SAT–aluminum joints was investigated as well. Increasing the telogen dose (from 5 to 15 wt. parts) caused significant improvement in the adhesion (+315% and +184%), tack (+147% and +298%), and cohesion (+414% and +1716%) of SATs based on MAT-T and MAT-B, respectively. Additionally, MATs with high telogen content (especially the MAT-T-type) improved the resistance of cured joints to aviation fuel, humidity, and elevated temperature. The highest overlap shear strength values were registered for SATs based on MATs containing 7.5 wt. parts of CBr4 (16.7 MPa) or 10 wt. parts of CBrCl3 (15.3 MPa).