Polymer Films For Applications Research Articles

Application of Polymer Films in High-Voltage Insulation Structures

Application of Polymer Films in High-Voltage Insulation Structures

Application of polymer films in high-voltage insulation structures

Application of polymer films in high-voltage insulation structures

Formation and applications of polymer films with gas-phase aggregated nanoparticles: A brief review

Nanoparticles (NP) of different types, especially metal ones, are of high interest for research and industry due to a wide spectrum of unique physical and chemical properties. Among various synthesis methods, the gas-phase aggregation of clusters/NPs is a technique providing a number of advantages in tailoring the composition, structure and spatial arrangement of materials on the nanoscale. Depositing or embedding the NPs on/in polymer films can improve the key functional properties and bring additional convenience in practical use. Therefore, there has been an active research on the development of such composite films in the past decade. The paper overviews the main approaches for covering and filling the thin polymer films with NPs produced by gas aggregation sources and provide brief review on several application areas of such composite materials, where the capabilities to control surface roughness, wettability, optical and electrical properties play an important role. The review is finalized by the discussion of current challenges of the method and prospective ways of the development.

Application of polymer film of barium titanite nanoparticles in human sports rehabilitation training

This paper studies the factors that improve the output performance of barium titanite nanoparticle generators for the energy supply of wearable electronic devices and the actual application requirements of human body motion monitoring statistical generator based on barium titanite nanoparticles. We designed and constructed a flexible barium titanite nanoparticle generator based on core-shell coaxial structure capable of human body motion energy collection and motion state sensing. The thesis uses barium titanite nanoparticle generators to convert low-frequency, different-amplitude human body motion energy into electrical energy. It is an effective and environmentally friendly solution to the problem of energy supply for wearable electronic devices.

Efficiency of Novel Antimicrobial Coating Based on Iron Nanoparticles for Dairy Products’ Packaging

The main function of food packaging is to maintain food’s quality and safety. The use of active packaging, including antimicrobial materials, can significantly extend the shelf life of food. Many of these packaging solutions are based on the application of polymer films containing metal nanoparticles (e.g., Ag, Au, Cu) or metal oxides (e.g., TiO2, ZnO, MgO). However, the use of iron nanoparticles is rarely mentioned. In the study, polylactide (PLA) films containing zero-valent iron (ZVI) were made by casting method. Pure PLA films and PLA films with the addition of Fe2O3 were used as comparative materials. The composition and structure of ZVI/PLA films were evaluated with scanning electron microscopy. The XRD spectra performed on ZVI/PLA films confirmed the presence of iron in the packaging material and revealed their oxide form (Fe2O3). The addition of zero-valent iron in the concentration 1%, 3%, or 5% resulted in the formation of crystallographic planes measuring 40.8, 33.6, and 28.6 nm, respectively. The color and gloss of the films, and their antimicrobial activity against bacteria (Bacillus subtilis, Escherichia coli, Staphylococcus epidermidis) and fungi (Geotrichum candidum, Rhodotorula rubra) were also examined. The PLA films with addition of 3% of ZVI (w/w) inhibited the growth of all tested organisms in contrast to PLA and PLA/Fe2O3 films. The addition of ZVI to polymer matrix caused changes in its appearance and optical properties. The ZVI/PLA coating used on polyolefin film allowed to extend the shelf life of goat cheese packed in examined material to 6 weeks. Considering the antimicrobial properties of the ZVI/PLA films and PLA biodegradability the obtained material can be successfully applied in the food industry.

Spontaneous Phase Separation of Poly(3‐hexylthiophene)s with Different Regioregularity for a Stretchable Semiconducting Film

AbstractHighly regioregular (RR) poly(3‐hexylthiophene)s PHTs are known to exhibit excellent electrical properties in comparison to chemically identical but regiorandom (rr) PHTs. In this study, distinct RR (97% and 55%)‐graded PHTs are subjected to solution blending to spontaneously separate the high‐RR PHT chains from the low‐RR PHT media and develop highly conjugated nanodomains in both solution and film. In the spun‐cast blend films, the rr PHT matrix imparts sufficient deformability of the channel layer required for stretchable organic thin‐film transistors (OTFTs), compared to neat RR PHTs and blends with a deformable polymer. OTFTs including RR PHT/rr PHT blend films show excellent hole mobility (µ) values up to 0.13 cm2 V−1 s−1, surpassing that of the best RR PHT films (0.026 cm2 V−1 s−1) fabricated by ultrasound solution pretreatment. Furthermore, a 50% stretched RR PHT/rr PHT film maintains ≈55% of its µ value at no strain, while RR PHT films show a sudden decrease in µ even at 10% stretch. The simple blending approach imparts deformability to π‐conjugated polymer films for application in stretchable OTFTs.

Preparation of Stable Wetting Surface by Hyperthermal Hydrogen Induced Cross-Linking of Poly(acrylic acid) on Poly(chloro-p-xylylene) Film

Enhancing surface wetting is very critical for various applications of polymer films. Although existing modification methods (e.g., UV radiation and plasma treatments) can improve the wetting of polymer films by inserting hydrophilic groups, the resultant polymer surface is unstable and shows strong hydrophobic recovery in a short time (less than 1 day) due to the rearrangement of the polymer chains. Herein, we report a new approach to prepare stable wetting surface by cross-linking hydrophilic poly(acrylic acid) (PAA) molecules on poly(chloro-p-xylylene) (PPXC) films via hyperthermal hydrogen induced cross-linking (HHIC) treatment. With the HHIC treatment, the polar functionalities of PAA (e.g., −COOH) can be preserved through selective cleavage of C–H bonds and subsequent cross-linking of resulting carbon radicals generated on PAA and PPXC chains. HHIC-treated PAA–PPXC film shows an excellent wetting stability, of which WCA and surface energy stay almost the same over 40 days. The improved wetting stabi...

The Distribution of Glass Transition Temperatures in Ultrathin Polymer Films Controlled by Segment Density or Interfacial Interaction

Nowadays, the microscopic mechanism controlling the distribution of local glass transition temperatures (Tgs) across thin polymer films is still unclear and thus large‐scale applications of polymer films are restricted. Dynamic Monte Carlo simulations are performed to investigate the key factors dominating the distribution of layer Tgs in two kinds of capped ultrathin films with and without attractive polymer–substrate interactions, respectively. For the film without polymer–substrate interaction, the interfacial layer Tg is lower than the middle layer Tg. Additionally, the layer Tgs and the layer segment densities below Tg are linearly correlated, indicating that polymer density determines the distribution of layer Tgs. However, for the films with polymer–substrate interactions, the interfacial layer Tg increases dramatically with the raise of interfacial interactions, while the middle layer Tg decreases slightly. The interfacial layer Tg is proportional to the strength of interfacial interaction, while the middle layer Tg is linearly correlated with the segment density of the middle layer below Tg. Namely, interfacial interaction is the main factor dominating the interfacial layer Tg, while segment density controls the middle layer Tg. image

Heterogeneous fluorine-containing surface macro-, micro- and nanostructures in polymer films and their applications

The methods of heterogeneous macro-, micro- and nanostructure formation on the surfaces of polymer films via their modification with gaseous fluorine have been considered. The successive fluorination and sulfonation of polyolefin films allows the synthesis of heterounit bi- and polyfunctional molecular fragments, thereby providing controlled chemical structuring at the nanolevel within a macromolecular segment. The combined use of the above methods of polymer-surface modification and intermediate film deformation under uniaxial tension results in the formation of surface microzones with fluorinated and sulfonated structures. Fluorinated and sulfonated macro- and microzones are formed via mechanical fracture of the fluorinated layer before sulfonation or via shielding of the polymer surface before sulfonation according to a given pattern through photolithographic methods. The practical applications of polymer films with heterogeneous surface structures are discussed.

Obtaining of Polymer Films from Nylon 6/Bentonite Clay Nanocomposites: Structural Characterization

The nanocomposites are hybrid materials where at least one of the components has nanometric dimensions and in the same way as traditional composites are formed, one of the components is the matrix in which nanoparticles are dispersed. One of the possibilities of applications of nanocomposites is to obtain polymer films for applications in the barrier, or separation promoted by the dispersion of the clay lamellae. In this work, nanocomposites of nylon 6/bentonite clay were obtained by melt intercalation. The used clay was the Brasgel PA, and quaternary ammonium salt was Praepagen-HY, used in organophilization of the clay. By XRD, it was observed the disappearance of the characteristic peak of clay, and this can be facilitate the possible exfoliation of clay in the produced films from the nanocomposite. By SEM, it was observed, an apparently dense layer with no pores.

Soft microorigami: self-folding polymer films

Fabrication of 3D objects using folding of thin films is a novel and very attractive research field. The manuscript overviews recent advances in development and application of polymer films, which are able to fold and form 3D structures.

Raman study of polyaniline nanofibers prepared by interfacial polymerization

Polyaniline nanofibers were synthesized by interfacial polymerization of aniline. Polyaniline so formed was studied using transmission electron microscopy, scanning electron microscopy, UV–vis and Raman spectroscopy. TEM of polymer dispersion shows the presence of fibers having diameter around 30–80 nm. Strikingly different Raman spectra were observed from the polyaniline film, which were related to two dissimilar areas on the film. SEM of polyaniline films shows fibrous as well as flake like structures scattered in fiber matrix. Raman spectra of the films heat treated from 25 °C to 300 °C were taken to study the structural variations induced by the change of temperature at these two regions. Many applications of polymer films are dependent on the homogeneity of the systems. In this work we intend to employ Raman Spectroscopy as an indispensable tool for looking into the non-uniformities of the polyaniline films.

Amplified spontaneous emission from a conjugated polymer undergone a high-temperature lithography cycle

We investigated the amplified spontaneous emission (ASE) and waveguiding properties of a conjugated polymer film after a heating cycle typical of soft lithography procedures. We found a maximum gain coefficient of 8cm−1, with excitation density and length thresholds for ASE-induced line narrowing of 200μJcm−2 and 0.9 mm, respectively. Importantly, we found a loss coefficient of the organic slab as low as 5.4cm−1, which is among the best results reported for organic waveguide amplifiers. These results are important in view of the application of polymer films as active layers for laser devices realized by patterning with high-temperature mechanical lithographies.

Characterization of freestanding polymer films for application in 351-nm, high-peak-power laser systems

Perfluorinated pellicles are screened for thickness uniformity, absence of birefringence, photolytic stability under prolonged UV irradia- tion, and survival strength under pulsed (0.5-ns) high-peak-power laser irradiation. Results prove them to be extraordinarily robust against laser damage, photolytically stable, and better in transmitted wavefront quality than can be measured by state-of-the-art interferometry. © 1998 Society of Photo-Optical Instrumentation Engineers. (S0091-3286(98)04102-6)

Applications of polymer films and Nujol mulls to spectroscopic studies at low temperatures: electronic spectra of chromate, dichromate, chlorochromate, manganate and permanganate ions at 12–77 K

Electronic absorption spectra have been obtained for chromate, dichromate, chlorochromate, manganate and permanganate ions in argon and dinitrogen gas matrices, poly(vinyl alcohol) films and Nujol mulls at c. 12 and 77 K. All the ions showed well resolved vibrational progressions. There was a good correspondence for the data for caesium chromate between frozen gas matrices, polymer films and Nujol mulls and that previously obtained using single crystals, doped crystals and thin films. The relative ease, speed and inexpensiveness of procedures using polymer films and particularly mulls, which are described for the first time, makes them ideal for low temperature studies especially where gas matrix, organic glass and doped crystal studies are not feasible, e.g. potassium chlorochromate which is not volatile and which disproportionates in solution.