Polymer Tape Research Articles

Аналіз технічних вимог і методів випробування матеріалів для дорожньої розмітки, як підґрунтя для нових стандартів

Introduction. Horizontal road markings are a crucial element of road safety, traffic organization and flow management. They also enhance the road's capacity by more than 20 % and reduce the number of road traffic accidents. The modern development of the road sector is characterized by increasing demands on road markings. Today, the choice of materials for road markings is vast and includes: paints, cold and hot-applied plastics, polymer tapes, pre-formed products, retroreflective glass microbeads, and more. Each material has a unique set of properties related to durability, retroreflectivity, application cost, and life cycle. Problem Statement. The expanded range of materials complicates the selection process for road markings. The choice must account for various factors, including the type of marking, road conditions (curves in plan, intersections, roads with high traffic volume, etc.), road surface material, and its roughness. To select the proper materials for road markings, road traffic load level and expected service life must be considered. To make an optimal choice, it is essential to test the quality characteristics of materials through evaluations of their physical-mechanical, technological, and functional properties.

Cytotoxicity of two fluoride-releasing adhesive tapes.

Sodium fluoride-polyvinyl alcohol (NaF-PVA) tape was developed to deliver fluoride to teeth by adding fluoride to polymer tape. Previous studies have demonstrated that tapes are effective and have antimicrobial properties. This study aimed to evaluate the cytotoxicity of two fluoride-releasing adhesive tapes. We investigated two polyvinyl alcohol (PVA) tapes: (i) a fluoride-PVA (F-PVA) tape, and (ii) a pullulan-incorporated F-PVA (PF-PVA) tape. The cytotoxicity test was conducted on human gingival fibroblasts (HGF) and human periodontal ligament (PDL) cells. Using an adhesive tape containing fluoride, we performed the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay on these cells. Genetic analysis of the cells was performed to conduct a stability test on humans. In the MTT assay, PF-PVA had 66% greater cytotoxicity than control by PDL and 69% by HGF. F-PVA showed less cytotoxicity than PF-PVA by 29% in PDL and 33% in HGF. Gene ontology (GO) analysis and gene set enrichment analysis (GSEA) were performed as gene expression analyses. GO analysis indicated that PF-PVA displayed more expression changes of genes related to cytotoxicity than F-PVA. In addition, GSEA found more inflammatory response associations in PF-PVA than in F-PVA. MTT and genetic testing yielded comparable results.

A study on real-time quantitative thermal analysis of composite tapes

Generating vast volumes of data by continuously moving systems in industrial environments presents a significant challenge. The carbon fiber reinforced polymer (CFRP) tapes control exemplifies this issue, with a strongly increasing production these last decades, and yielding several tens of meters to inspect within a short time. It leads to a pressing need for rapid and effective quality control and decision-making systems. This study introduces an innovative method for mitigating data overload by focusing on the defective sections of the tape by creating a corresponding virtual twin to assess fiber content variations. Data analysis techniques are employed to differentiate flawless from faulty regions and thermal methods are applied to characterize observed defects. This article presents a comprehensive approach for enabling the analysis of tens of meters of tapes at 25 cm/s speed scroll within a competitive timeframe.

Temperature-Controlled in-situ Tensile Tests of Polymer Tape with Single Particles

X-ray Computed Tomography (CT) combined with mechanical testing can deliver great insights in the damage mechanisms of polymers. Depending on the application area of the polymer, temperatures can be very high or low – leading to a different performance compared to room temperature. In this study, the influence of the temperature on damage mechanisms of a single particle in a polymer matrix should be investigated. Thus, three polymer tensile test specimens (length 30 mm; width 10 mm) – each containing a single particle – were cut out of a tape with a thickness of 0.5 mm and tested at various inspection temperatures. CT measurements were performed with the RX Solutions Easytom 160 laboratory CT device with a voxel size of (3 µm)³. Each specimen was scanned twice, namely at 0% strain and 30% strain. As inspection temperatures 0 °C, 22 °C and 60 °C were chosen. It is shown that temperature can have a great impact on the performance and damage mechanisms of a polymer, especially if a particle is present in the polymer matrix.

Examination of gecko-inspired dry adhesives for heritage conservation as an example of iterative design and testing process for new adhesives

AbstractRarely within the conservation of cultural heritage have conservation professionals been lucky enough to have materials custom-designed to meet their requirements. Most of the time the field must adapt solutions developed for other applications. The research presented here was initiated as part of a long-term aim to develop new adhesives for heritage conservation. Gecko-inspired dry adhesives (GDAs) are polymer tapes with micropatterns that are based on the adhesive properties of the pads of gecko lizard feet: they have strong normal and shear adhesion with low peel adhesion. They present potentially versatile and reversible adhesives for heritage conservation applications; which do not require solvents for activation or for removal, and do not migrate or off-gas. In nature, geckos can adhere with their feet to any surface they walk on. This is possible because of micro- and nanostructures on their feet that attach to surface via van der Waals forces. Practical studies aimed at comprehensively assessing their properties, and biomimetic solutions in heritage conservation are still sparse at present. This research has the objective of assessing GDAs properties by mechanical testing of adhesive joints, as well as physical and chemical characterisation of the materials used. The research has also included a museum case study and a two-year natural ageing test. The testing has shown that the GDAs can perform very well as an adhesive patch on the reverse of gelatine-based photographs, achieving shear forces between 0.80 N and 48.10 N on 8 cm2 lap joints (depending on the type of the GDA) and peel forces between 0.20 N and 0.47 N over 2 cm of peel front. This is lower than forces exceeding 1 N recorded in widely available pressure-sensitive tapes. This shows that GDAs may have the potential of a sufficiently strong, yet easily removable adhesive that works well on materials widely present in museum collections.

Liquid metal-assisted hydrothermal preparation of cobalt disulfide on the polymer tape surface for flexible sensor

Liquid metal-assisted hydrothermal preparation of cobalt disulfide on the polymer tape surface for flexible sensor

Piezo/Triboelectric Nanogenerator from Lithium-Modified Zinc Titanium Oxide Nanofibers to Monitor Contact in Sports

The need for technological innovation in competitive sports is crucial for self-monitoring and smart decision making. In this work, we demonstrate how intelligent sports and smart decision making can be achieved in cricket and boxing using lithium-modified zinc titanium oxide (LZTO) nanofibers based on piezoelectric nanogenerators (PENGs) and triboelectric nanogenerators (TENGs). Zinc titanium oxide (ZTO) nanofibers synthesized using electrospinning followed by a calcination technique are modified with lithium to increase the output of the nanogenerator. An optimized PENG is fabricated using 25 wt % loading of LZTO (d33 = 214 pm/V) in a poly(vinylidene fluoride) (PVDF) matrix as a double-layered structure and yields an open-circuit voltage (Voc) of 35 V and a short-circuit current (Isc) of 1.6 μA by manual tapping. To fabricate the TENG, Kapton and LZTO are used as negative and positive tribolayers, while Cu and adhesive polymer tape are used as the electrode and spacer, respectively. Furthermore, a hybrid nanogenerator (HNG) is fabricated by combining the PENG and TENG to produce a rectified voltage, current, and power density of up to 75 V, 3.2 μA, and 240 μW/cm2, respectively. These HNGs are integrated with a punching bag and demonstrated to differentiate among the six types of punches in boxing. Furthermore, PENGs are used in cricket to monitor the number of balls middled on the bat during practice and the contact of the ball with the bat and stumps for smart decision making. All kinds of lab-scale testing are done for these applications, which pave a way for exploring the frontiers in nanogenerator applications in sports as maintenance-free and self-powered sensing technology.

Numerical investigation of the application of voxel based meshes for stochastic tow based discontinuous composites

Stochastic tow based discontinuous composites (STBDC) are fabricated from compression molding chips of chopped and slit pre-impregnated uni-directional carbon fiber reinforced polymer (CFRP) tape. The discontinuous mesostructure gives the material system increased moldability versus continuous fiber composites; however, this gives the material highly variable effective properties. For applications in finite element analysis, the mesostructural morph ology of STBDCs can be idealized using a non-conforming voxel-based mesh framework. The objective of this study is to investigate the effect of mesh coarsening on the elastic response of STBDC simulations. Furthermore, a method for the homogenization of the voxel based mesostructure is considered, with results compared against detailed simulations of the mesostructure. The results demonstrate that coarse mesostructures provide similar effective properties and internal stress distributions as detailed models. Furthermore, simulations with homogenized properties provide nearly identical results to detailed simulations for a fraction of the simulation time. • Voxel-based representative volume elements can be used to generate finite element models and calculate effective properties. • Chips size influences the magnitude of internal stress concentrations observed in representative volume elements. • Method for homogenization provides a similar elastic response as detailed representative volume elements. • Simulations capture the chip size effects on the effective modulus.

Development challenge for synthetic polymer fibers and tapes: improving toughness

Development challenge for synthetic polymer fibers and tapes: improving toughness

Thin-Film Heterostructures Based on Co/Ni Synthetic Antiferromagnets on Polymer Tapes: Toward Sustainable Flexible Spintronics.

Synthetic antiferromagnets with perpendicular magnetic anisotropy (PMA-SAFs) have gained growing attention for both conventional and next-generation spin-based technologies. While the progress of PMA-SAF spintronic devices on rigid substrates has been remarkable, only few examples of flexible thin-film heterostructures are reported in the literature, all containing platinum group metals (PGMs). Systems based on Co/Ni may offer additional advantages with respect to devices containing PGMs, i.e., low damping and high spin polarization. Moreover, limiting the use of PGMs may relieve the demand for critical raw materials and reduce the environmental impact of related technologies, thus contributing to the transition toward a more sustainable future. Here, we discuss for the first time the realization of Co/Ni-based PMA-SAFs on polymer tapes and exploit it to obtain flexible giant magneto-resistive spin valves (GMR-SVs) with perpendicular magnetic anisotropy. Several combinations of buffer and capping layers (i.e., Pt, Pd, and Cu/Ta) are also investigated. High-quality flexible SAFs with a fully compensated antiferromagnetic region and SVs with a sizable GMR ratio (up to 4.4%), in line with the values reported in the literature for similar systems on rigid substrates, were obtained in all cases. However, we demonstrate that PGMs allows achieving the best results when used as a buffer layer, while Cu is the best choice as a capping layer to optimize the properties of the stacks. We justify the role of buffer and capping layers in terms of different interdiffusion mechanisms occurring at the interface between the metallic layers. These results, along with the high robustness of the samples' properties against bending (up to 180°), indicate that complex and bendable Co/Ni-based heterostructures with reduced content of PGMs can be obtained on flexible tapes, allowing for the development of novel flexible and sustainable spintronic devices for applications in many fields including wearable electronics, soft robotics, and biomedicine.

Numerical Comparison of the Elastic Response of Stochastic Tow-Based Composites with Different Chip Consolidation Methods

Stochastic tow based discontinuous composites (STBDC) are fabricated from the compression molding of chips made from chopped and slit pre-impregnated uni-directional carbon fiber reinforced polymer (CFRP) tape. The discontinuous mesostructure gives the material system increased moldability versus continuous fiber composites allowing complex three-dimensional parts to be manufactured. However, the discontinuous mesostructure creates challenges for engineers designing parts as the effective properties are variable. Furthermore, the properties have been shown to be a function of the consolidation method of the chips. This study uses finite element analysis simulations of mesostructural representative volume elements to compare the elastic response and characteristics. The results are compared to the available literature regarding the elastic response STBDCs.

Influence of Epoxy Glue Modification on the Adhesion of CFRP Tapes to Concrete Surface.

Strengthening structural concrete, steel or wooden elements with reinforcement tapes is currently a popular method of extending the durability of buildings. In the glued joint Carbon Fibre Reinforced Polymer (CFRP) tape—concrete substrate, the most critical element is the adhesive layer connecting both materials. The glued joint participates in the transfer of stresses between the reinforced element and the reinforcement tape. Among the numerous analyses of this type of joint, the work resulting from the action of shear stresses (shearing) is considered most frequently, which also results from the originally developed computational models emerging with the development of research on the processes of adhesive effectiveness. The subsequent theories considered the share of other stresses, which is also related to the complex nature of the phenomenon of glue adhesion on various surfaces. Research shows the possibility of modifying the adhesion of the glue by altering its composition and the target surface of application. The study contains the results of research on the possibility of changing the adhesion of the glue to a concrete surface prepared by grinding and sandblasting. The selected epoxy resin has been modified by using the additives of microsilica and carbon nanotubes. Effective mixing of ingredients was achieved due to the use of sonication in the mixing process. Then, the adhesives prepared in this way were used to stick fragments of CFRP tape to concrete surfaces: cleaned, ground and sandblasted. A modified version of the pull-off test was used to determine the effectiveness of adhesion the CFRP tapes to concrete. The results are the final stage summarizing a series of studies including other parameters affecting the bonding efficiency and durability of adhesive bonds.

High-Velocity Stretching of Renewable Polymer Blends

We evaluated the influence of blending various renewable polymer grades and amounts to allow for high stretchability during stretching at 800 mm/s to produce polymer tapes with high Young’s moduli E and yield stress σy similar to industrial production of non-degradable synthetic polymers. Renewable polymer blends based on TPS, PBAT, and PLA with high stretchability as well as high E and σy of stretched tapes comparable to high-density polyethylene (PE-HD) and isotactic polypropylene were identified. High stretchability (up to 380%) was facilitated with TPS-PBAT tapes and comparably high E (up to 5000 MPa) and σy (up to 160 MPa) of stretched tapes were obtained for mixtures of different PLA grades resulting in E-moduli exceeding that of PE-HD. A balance of these properties approaching those of synthetic polymers was achieved with PLA-PBAT blends (stretchability: 340%, E: 4500 MPa, σy: 120 MPa).

Polymer multilayers enabled stable and flexible Au@Ag nanoparticle array for nondestructive SERS detection of pesticide residues

The development of flexible and robust plasmonic substrates has become a hot research topic in simplifying and extending the application of surface-enhanced Raman scattering (SERS) technique for real-world analysis. In this work, a facile method to fabricate an Au@Ag nanoparticle array sandwiched between the adhesive acrylic polymer tape and polyethene terephthalate (PET) film (T/Au@Ag/PET) as a high-performance SERS chip was reported for nondestructive detection of thiram on fruit peels. For this SERS chip, the ordered Au@Ag nanoparticle array formed by the self-assembly method was closely-packed, which generated high‐density sub‐3‐nm gaps and could produce high reproducible and sensitive SERS enhancement effects. The measurement of crystal violet with the limit of detection of 7.24 × 10−10 M was realized by targeting Raman shift at 1177 cm−1. Moreover, the excellent flexible feature of acrylic polymer tape enabled the substrate to withstand a tensile strain value of 20% for three cycles without significantly losing its SERS activity. By covering with a PET film, the SERS chip could maintain 87% SERS activity after storage for 60 days in the air environment, and could well withstand the influence of harsh conditions such as high temperature and ultrasound treatments. As a proof of the concept, the SERS tape was directly used to detect thiram on apple, tomato, and cucumber peels via a simple sampling-and-detection procedure, and the detection limit of 5 ng/cm2 was achieved. The T/Au@Ag/PET SERS chip should hold a promising candidate for food safety analysis in the future.

Tailoring the laser irradiation effects by covering the targets with polymer tapes

Abstract Three different semiconductor materials (Si, Ge and GaAs) covered with four different polymer tapes are irradiated in air at 1, 50, 100 and 200 number of laser shots. The morphology of irradiated samples is studied through optical microscopy, scanning electron microscopy and optical profilometry. Heat affected zone (HAZ) of target materials is decreased after covering them with polymer tapes. Different morphologies such as crater, cracks, cavities, dendritic structures, pyramid like structures, veins like structures, periodic surface structures and micro-as well as nano-particles are formed on the surface of target materials. The profilometric measurements are performed in order to determine the depth of the formed craters which is increased with increasing number of laser shots. This study reveals that by applying some suitable polymer tapes, the undesirable laser irradiation effects such as HAZ and production of other micro structures can be avoided. The controlled ablation effects which are normally achieved with femtosecond lasers, can also be obtained with nanosecond lasers using this strategy. The proposed study can receive wide range of attractive applications in laser cutting and laser machining processes with controlled laser irradiation effects.

Laboratory and Numerical Analysis of Steel Cold-Formed Sigma Beams Retrofitted by Bonded CFRP Tapes.

In this paper, the retrofitting method of thin-walled, cold-formed sigma beams using bonded carbon fibre reinforced polymer (CFRP) tapes is proposed. The effectiveness of the presented strengthening method is investigated by the means of laboratory tests and numerical analysis conducted on simply supported, single-span beams made of 200 × 70 × 2 profile by “Blachy Pruszyński” subjected to a four-point bending scheme. Special attention is paid to the evaluation of possibility to increase the load capacity with simultaneous limitation of beams displacements by appropriate location of CFRP tapes. For this purpose, three beams were reinforced with CFRP tape placed on the inner surface of the upper flange, three with CFRP tape on the inner surface of the web, three beams with reinforcement located on the inner surface of the bottom flange, and two beams were tested as reference beams without reinforcement. CFRP tape with a width of 50 mm and a thickness of 1.2 mm was used as the reinforcement and was bonded to the beams by SikaDur®-30 adhesive. Precise strain measurement was made using electrofusion strain gauges, and displacement measurement was performed using two Aramis coupled devices in combination with the Tritop machine. Numerical models of the considered beams were developed in the Finite Element Method (FEM) program Abaqus®. Experimental and numerical analysis made it possible to obtain a very high agreement of results. Based on the conducted research, it was proved how important is the impact of the applied reinforcement (CFRP tapes) in thin-walled steel structures, with respect to the classic methods of strengthening steel building structures.

Определение конструкторско-технологических параметров намотки герметичных топливопроводов из полимерной пленки

The paper considers issues related to technology of manufacturing pipelines by winding polymer film materials and assessing their tightness with respect to gaseous and liquid fuel components. The shell is made by winding the required number of layers of continuous film tape with a given width, thickness and overlap on a rigid removable mandrel. The multilayer film structure of the shell made by winding a narrow polymer tape is considered as a computational model of the sealing shell of the pipeline. The tightness of the polymer pipeline shell is determined both by the physical and chemical parameters of the film material (permeability and diffusion coefficients) and by the structural and technological parameters of the wound shell. The simulation results allowed determining the main structural and technological parameters of the winding process as applied to the polyimide-fluoroplastic film PMF-352, which provide the total leakage of the film fuel lines within the requirements.

Alkaline Battery Separators with High Electrolyte Absorption from Forced Assembly Coextruded Composite Tapes

In this work, two-component fibrous separators with high electrolyte absorption were fabricated by the delamination of oriented polymer tape which was produced using a unique coextrusion and multip...

Design and fabrication of a Ti/Al thin-film electrode in the meander-shaped microchannel and its application for promoting capillary-driven dielectrophoresis blood separation

In this article, a Ti/Al thin film with Ti as an adhesive layer that merits high conductivity, excellent adhesion and low cost is used as the electrode in a biomedical blood separation chip instead of the conventional biomedical electrode mostly made of expensive Au and/or Pt. The design and fabrication of the meander-shaped Ti/Al thin-film electrode are studied for the application to promote the capillary-driven dielectrophoresis (DEP) blood separation chip. The meandered electrode with a castellated profile of 0.6 and 0.2 mm spacing instead of the flat one is designed on the glass substrate to produce an asymmetric electric field for the DEP force to separate the blood. The meander-with-castellated electrode shape and gap affects the electric field gradient on the separation performance. The patterning of the electrode was performed by the low-cost CO2 laser-ablated polymer tape rather than an expensive-complex photolithography process and then followed by sputtering together with lift-off process. The Ti/Al thin film is coated on the channel backside rather than inside for contactless DEP to avoid the contact pollution of the sample as well to reduce the operation voltage. The COMSOL Multiphysics® simulation of the electric field and the blood separation test were done for verifying the design and experiment. In the simulation, the 0.2 mm castellated electrode can greatly enhance the asymmetric electric field peak of 24000 V m−1 compared to the flat electrode of about 12000 V m−1. Also, the 0.2 mm gap castellated electrode with three-time electric-field-gradient-pulse frequency can enhance the DEP force compared to the 0.6 mm gap electrode. In the experiment, the blood chip of 0.2 mm castellated electrode with the highly increased electric field and DEP force can shorten the starting separation time from 533 s to 253 s and enhance the separation efficiency from 20.0% to 51.7% at the applied voltage of 5 V and 1 MHz.

High-velocity stretching of polyolefin tapes

Stretched polyolefin films and tapes are used in many packaging applications, such as BigBags. Stretching is elongation of polymer tapes in one direction, resulting in improved mechanical properties. Both, amorphous and crystalline polymers are in principle stretchable but linear, unbranched macromolecules are highly stretchable. Hence, the stretchability of e.g. branched low density polyethylene (PE-LD) is lower than of high-density polyethylene (PE-HD). Basic requirements for stretching of thermoplastics are known, but correlations between material parameters and stretching behaviour are scarce. Moreover, stretching of polymers is usually studied with tensile tests at stretching velocities much lower (1–500 mm/min) than in industrial processes (400–1000 mm/s), while results from high-velocity stretching tests or on production machines have not been published as of yet. We investigated high-velocity (800 mm/s) stretching of PE-LD, PE-HD and isotactic polypropylene films and tapes and which stretching parameters resulted in maximum mechanical properties. It was found that sample geometry, temperature, and the degree of stretching have a significant influence on the properties of stretched tapes, e.g. higher stretching temperature resulted in higher mechanical properties and orientation of crystallites. Furthermore, about 80% of the maximum stretching degree resulted in maximum mechanical properties.