24 research outputs found
Comparative Evaluation of Cu(acac)<sub>2</sub> and {[Cu(μ-<i>O</i>,<i>O</i>′-NO<sub>3</sub>) (L-arg) (2,2′-bpy)]·NO<sub>3</sub>}<sub>n</sub> as Potential Precursors of Electroless Metallization of Laser-Activated Polymer Materials
This paper presents a comparative assessment of Cu(acac)2 and {[Cu(μ-O,O′-NO3) (L-arg)(2,2′-bpy)]·NO3}n as potential precursors for the electroless metallization of laser activated polymer materials. Coatings consisting of polyurethane resin, one of the two mentioned precursor compounds, and antimony oxide (Sb2O3), as a compound strongly absorbing infrared radiation, were applied on the polycarbonate substrate. The coatings were activated with infrared Nd: YAG laser radiation (λ = 1064 nm) and electroless metallized. It was found that after laser irradiation, a micro-rough surface structure of the coatings was formed, on which copper was present in various oxidation states, as well as in its metallic form. For selected parameters of laser irradiation, it was possible to deposit a copper layer on the coating containing Cu(acac)2 and Sb2O3, which is characterized by high adhesion strength. It was also found that the {[Cu(μ-O,O′-NO3) (L-arg)(2,2′-bpy)]·NO3}n complex was not an effective precursor for the electroless metallization of Nd:YAG laser activated coatings. An attempt was made to determine the influence of the precursor chemical structure on the obtained metallization effects
Impact of Accelerated Aging on the Performance Characteristics of “Green” Packaging Material of Polylactide
The paper presents the result of the research on the impact of the accelerated aging process on selected operational
properties of polylactide films containing natural antioxidants in the form of coffee, cocoa or cinnamon extracts.
The research was focused on mechanical properties important for the packaging industry from the point of view
of the reliability of the obtained products, i.e. tensile strength, relative deformation at maximum stress, relative
deformation at break, Young’s modulus, impact strength and storage module at various temperatures. The extracts
have a positive effect on the determined mechanical properties. The obtained results were very often better not
only than the values obtained for pure polymer, but also better than the values obtained for the film containing the
synthetic anti-aging compound. It can therefore be concluded that the proposed plant extracts will have a positive effect on the stability of the mechanical properties of the manufactured products, which will allow long-term,
reliable and safe operation of packaging. Proposed extracts can therefore be an alternative to the previously used
synthetic anti-aging additives
Study of montmorillonite modification technology using polyvinylpyrrolidone
In this work, a new method of modifying montmorillonite (Mt) with polyvinylpyrrolidone (PVP) was developed, which makes it possible to obtain modified Mt with different structures and modifier content simultaneously. The essence of the method consists in mixing colloidal solutions of Mt and PVP, processing the mixture with ultrasound, settling, and selecting individual layers of the final solution. Several methods, such as scanning electron microscopy (SEM), X-ray diffraction (XRD), thermal gravimetry (TG), differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR) spectroscopy, have been used to characterize pure substances and to study the structure and thermal behavior of the composites. It was established that PVP macromolecules could both intercalate in the interlayer space of Mt and form exclusively exfoliated Mt. In addition, under certain conditions, Mt flocculated with PVP can be obtained. It is shown that during intercalation, PVP macromolecules displace and replace montmorillonite water in the interlayer space of clay mineral
Riboflavin as a Biodegradable Functional Additive for Thermoplastic Polymers
With continuous development of biodegradable polymers, new areas of applications are intensively researched. Modifications of these polymers are commonly conducted by an extrusion compounding process. While additives are changing desired properties, biodegradability of such composites can be deteriorated. The aim of the work is to investigate a novel, functional, organic additive, riboflavin (vitamin B-2), in terms of thermal stability, extrusion processability, wettability, surface energy, especially biodegradability, and when compounded with PLA. Additionally, a comparison of unmodified PLA resin, as well as PLA-modified with inorganic talc—which is known for its nucleation promotion in a variety of polymers—to PLA with riboflavin, was presented. Research reveals the outstanding thermal stability of riboflavin and the sufficient extrusion process properties with no significant changes of wettability and, surprisingly, a significant degradation rate as compared to pure PLA or and PLA with talc. The obtained results do not exclude further modifications of PLA depending on the target application, e.g., antimicrobial agents, flame retardants, etc
Riboflavin as a Biodegradable Functional Additive for Thermoplastic Polymers
With continuous development of biodegradable polymers, new areas of applications are intensively researched. Modifications of these polymers are commonly conducted by an extrusion compounding process. While additives are changing desired properties, biodegradability of such composites can be deteriorated. The aim of the work is to investigate a novel, functional, organic additive, riboflavin (vitamin B-2), in terms of thermal stability, extrusion processability, wettability, surface energy, especially biodegradability, and when compounded with PLA. Additionally, a comparison of unmodified PLA resin, as well as PLA-modified with inorganic talc—which is known for its nucleation promotion in a variety of polymers—to PLA with riboflavin, was presented. Research reveals the outstanding thermal stability of riboflavin and the sufficient extrusion process properties with no significant changes of wettability and, surprisingly, a significant degradation rate as compared to pure PLA or and PLA with talc. The obtained results do not exclude further modifications of PLA depending on the target application, e.g., antimicrobial agents, flame retardants, etc
Laser Activated and Electroless Metalized Polyurethane Coatings Containing Copper(II) L-Tyrosine and Glass Microspheres
Polyurethane coatings containing copper(II) L-tyrosine and glass microspheres were laser irradiated and underwent electroless metallization. Various sizes of glass microspheres were incorporated into the polyurethane coating matrix in order to examine their effects on surface activation and electroless metallization. The surface of the coatings was activated by using ArF excimer laser emitting ultraviolet radiation (λ = 193 nm) using different number of laser pulses and their fluence. The effects of surface activation and metallization were evaluated mainly based on optical and scanning electron microcopies (SEM), energy-dispersive X-ray spectroscopy (EDX) and photoelectron spectroscopy (XPS). It was found that the presence of glass microspheres enabled the reduction in copper complex content, intensified the ablation process (higher cone-like structures created) and resulted in higher content of copper metallic seeds. On the other hand, the glass microspheres concentration, which was higher for lower size microspheres, was advantageous for obtaining a fully metallized layer
The Effect of Accelerated Aging on Polylactide Containing Plant Extracts
In this study, natural extracts of plant origin were used as anti-aging compounds of biodegradable polymers. Coffee (0.5–10 wt%), cocoa, or cinnamon extracts were added to the polylactide matrix. The obtained materials were subjected to an accelerated aging process (720, 1440, or 2160 h) at 45 °C and 70% relative humidity under continuous UV radiation. The effectiveness of the tested extracts was compared to a commercially available anti-aging compound, 2 wt% of butylated hydroxytoluene. Visual evaluation, scanning electron microscopy, melt flow rate, thermogravimetry, differential scanning calorimetry, tensile strength, and impact tensile tests were performed. We show that the use of smaller amounts of tested extracts is particularly advantageous, which do not adversely affect the properties of polylactide-based materials at low contents. At the same time, their effectiveness in stabilizing tested properties during the accelerated aging process is mostly comparable to or greater than the reference compound