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The purpose of this paper is to determine the influence of the loading velocity on textile bonds and sewn seam strength.

Commercially produced polyamide and polyester knitted fabric, and polyester woven fabrics as well as three commercially available monolayer urethane thermoplastic films were used in this research. Two layers of each fabric were laminated at 160°C temperature at 5.6 kPa for 20 seconds. Sewn specimens were joined applying (301) and (514) stiches for woven and knitted fabrics, respectively. The bond and sewn seam strength was investigated at different delamination loading velocities (50, 100, 150, 200, 300 mm/min). These values of velocities lies in the velocity interval which covers the different standard requirements for testing of the quality of textiles and their seams or were applied in the research works of previous scientists. As the influence of loading velocity was more significant for bond strength, the bond strength results were analyzed together with the analysis of bond rupture character.

The determined influence of the loading velocity on textile bonds strength has proved that the loading velocity in bond strength test is of high importance for the prediction of the behavior of clothing being in exploitation under different conditions. The opposite tendency was determined for the sewn seams, the strength of which was independent on loading velocity.

The influence of the loading velocity on textile bond and sewn seam strength was not analyzed in the previous research works published by other scientists. It was known that the standard velocity is 50 mm/min for seams and 100 mm/min for textiles strength testing. It was shown there that the real exploitation of a garment as a whole complicated heterogenic dynamic system could be simulated with changing loading velocities during their seam strength testing. It was also determined that the loading velocity makes different influence on bonded and sewn seams of textiles.

The purpose of this paper is to evaluate the air permeability of knitted fabrics containing elastane fibre and their seams applying both the new approach based on fabric thickness measurement at different pressures and standard method.

Investigations were performed with commercially available eight polyester knitted fabrics containing different elastane yarn proportion. Bonded seams were laminated applying the urethane thermoplastic adhesive film of 0.175 mm thickness. Bonds were laminated by heat at 5.6 kPa pressure applying pressing device GTK DEA 25 R at 140°C temperature for 40 s duration. Sewn seams were assembled with 607 covering chain stitch applying 5.0 stitches per cm density and 512 overedge chain stitch applying 5.0 stitches per cm density. Specimens without and with the seams were conditioned in standard atmosphere conditions according to the standard LST EN ISO 139 before air permeability testing according to the standard LST EN ISO 9237. Standard thickness of the investigated knitted fabric was determined according to the standard EN ISO 5084. It is known from literature that the porosity is dominant factor influencing the air permeability of knitted fabrics. Therefore, the assumption was made that due to fabric porosity knitted fabric thickness being measured at different pressures also may differ. Thus, the permeability property may also be related to the difference between fabric’s thicknesses being measured under different pressures which may be applied with different material thickness gauges.

There was shown that fabric assemblies make the significant influence on the textile permeability to air. The results obtained indicate that the air permeability of the investigated knitted fabrics depends not only on their structure parameters but also on the fabric seam type. Air permeability of the specimens with the seams was lower than one of specimens without the seams. The highest decrease in permeability which ranged from 19.9 per cent up to 60.0 per cent was determined for the bonds. Fabric specimens with 607 covering chain stitch seam were in the second place with regard to the previously considered parameter. And, their permeability was decreased from 0.6 per cent up to 52.6 per cent. Changes in the air permeability of the specimens with 512 overedge chain stitch seam were lowest in the range of investigated assemblies. Based on the determined results, it was concluded that the thickness difference of the specimens with and without seams measured at different pressures is related to fabric porosity which makes the significant influence on the air permeability.

The samples of investigated fabrics were taken from the two companies which manufactures leisure clothing and sportswear such as skiing or swimming costumes, etc. Thus, the obtained investigation results are significant not only for clothing science but also leads the improvement of clothing quality in fashion industry.

Assuring the comfort of the human body is one of the most important functions of clothing, especially of sportswear and leisure wear. Knitted fabrics should not only be elastic, but also have high air permeability for easily transmit of the perspiration from the skin to the atmosphere, thus making the wearer to feel comfortable. In this research, the air permeability of commercially available polyester knitted fabrics containing different amount of elastane was investigated and the influence of fabric assemblies on the air permeability property was evaluated. A new approach based on the fabric thickness measurement at different pressures and the standard methods for the evaluation of air permeability were used.

The purpose of this paper is to evaluate the influence of assembly type on the hand property of the polyester-knitted materials containing different amounts of elastane fibre.

The hand property of control textile materials specimens as well as assembled ones applying both adhesive bonding and sewing was evaluated analysing the typical pulling curves as well as the individual hand parameters, which were determined using the device KTU-Griff-Tester. The complex hand criterion Q was calculated for the complete assessment of both textiles and their assemblies’ hand by one numeral value.

It was shown that the fabric structure and assembly type have a significant influence on the knitted materials hand property. The complex hand criterion Q varied from 0.068 to 0.186, depending on the material structure, and it was decreased up to 42.6 per cent due to textile assemblies.

The determined research results are significant not only for clothing science but also leads to the improvement in clothing quality in fashion industry suggesting more ergonomic and original constructional decisions for clothes’ design, selection of most suitable assembly type and its place in overall garment area, which is very important for the development process of the slim fitted sportswear featuring with a very complicated construction, usually worn under intensive body movements causing rubbing effect to the skin.

Knitted fabrics should not only be elastic but also have perfect hand, thus making them to feel comfortable. But hand property of assembled textiles had not been investigated previously. Novelty and originality of this research was the objective and simple evaluation of the hand property for both knitted materials and their assemblies taking into account the overall skin sensorial comfort of a garment.

The number of articles on solvent‐based acrylic resins in the paint industry has decreased in the past two years. It is not entirely clear why this is, since acrylic resins serve a key function in the industrial coatings segment of the paint industry, because of their outstanding weathering performance. The fact that they are available in both thermoset and thermoplastic forms makes them highly versatile. Structurally they are capable of wide variation, as indicated by an article by Ailhaud [Peintures, Pigments, Vernis, 47, March (1971) p. 170] who reports on the properties of block copolymers based on a variety of different alkyl methacrylates.

Protection of medical personnel against pathogenic viruses is a challenging task for the world scientific community. The purpose of this paper is to collect, analyze, critique, rearrange and present the scattered information scientifically to form a base for product development for viral protection.

A huge range of recently available information has been collected, studied and arranged judiciously.

After an exhaustive study of this topic, it is possible to present all information in a manner that will be helpful to start product development activity on both sides of the Atlantic. Initially, various coated textiles with zero breathability were used to cover doctors, nurses and staff but thereafter microporous coatings replaced the poreless surface coatings. However, the pore size distribution in microporous films and coatings could not be controlled precisely and manufacturers could not claim the surface offered foolproof protection against viruses. Monolithic films are able to claim guaranteed protection against virus penetration, with sufficient breathability. Monolithic film technology has prime importance in protective clothing that has to be discussed judiciously. Permeability of block copolymers based monolithic films is an important feature for barrier materials, high performance impermeable breathable clothing and membrane separation processes.

This is a first paper in the field of viral barrier fabrics which will remain helpful to the scientific community to start further research work and product development.

The purpose of this paper is to synthesize and characterize a series of two-component aromatic waterborne polyurethane (2K-WPU) which is composed of non-ionic and anionic polyisocyanate aqueous dispersion and polyurethane polyol aqueous dispersion.

The polyisocyanate aqueous dispersion was synthesized through non-ionic and anionic hydrophilic modification procedures. The values of the hydrogen bonding index (HBI) and molecule structures of WPU were obtained by Fourier transform infrared (FTIR). The thermal, mechanical and water resistance properties of 2K-WPU films were investigated.

The appearance of non-ionic polyisocyanate aqueous dispersion and anionic polyisocyanate aqueous dispersion was colorless translucent pan blue and yellow opaque emulsions, respectively. FTIR not only showed that 2K-WPU was obtained from the polymerization of polyisocyanate component and polyhydroxy component by polymerization but also showed that the content of hydrogen bondings of anionic 2K-WPU (WPU 2) was higher than non-ionic 2K-WPU (WPU 1). The glass-transition temperature (Tg), storage modulus and water resistance of WPU 2 were higher than WPU1, whereas the thermal stability of WPU1 was better than WPU 2.

The investigation established a method to prepare a series of 2K-WPU which was composed of non-ionic or anionic polyisocyanate aqueous dispersion and polyurethane polyol aqueous dispersion. The prepared 2K-WPU film could be applied as substrate resin material in the field of waterborne coating.

The paper established a method to synthesize a series of 2K-WPU. The effect of HBI value and the molecule structure of soft segment on the thermal stability, mechanical and water resistance properties of 2K-WPU films were studied.

This paper aims to use the solvent–casting–evaporation method to prepare new bio-composites with thermoplastic poly(ether urethane) (TPU-polyether) as the polymer matrix and reinforced with natural chicken feather fibre (CFF).

To produce the bio-composites, 0 to 60 per cent·w/w of fibres in steps of 30 per cent·w/w were added to the polymer matrix. The uniformity of distribution of the keratin fibres in the polymer matrix was investigated via scanning electron microscopy, and the results suggested compatibility of the TPU-polyether matrix with the CFFs, thereby implying effective fibre–polymer interactions.

Addition of natural fibres to the polymer was found to decrease the mass loss of the composites at higher temperatures and decrease the glass transition temperature, as well as the storage and loss modulus, at lower temperatures, while increasing the remaining char ratio, storage modulus and loss modulus at higher temperatures.

The investigation confirmed that waste keratin CFF can improve the thermo-mechanical properties of composites, simply and cheaply, with potentially large environmental and economic benefits.

Poly(ethylene terephthalate) (PET) waste from soft drink bottles was incorporated into palm olein alkyd to produce new polyol for use in polyurethane resins as surface protection on metal surfaces.

Alkyd was prepared from palm olein, glycerol and phthalic anhydride. PET underwent simultaneous glycolysis and transesterification reactions with the alkyd. Varying the amount of PET has led to polyols with different viscosities. Polyurethane resins were produced by reacting the polyols with toluene diisocyanate. The resins were coated on mild steel panels and cured. Performances of the cured films were tested.

The polyurethanes (PU) resin cured to a harder film with better thermal stability. Films showed excellent adhesion properties, while higher content of PET exhibited higher pencil hardness, better water, salt, acid and alkali resistance.

Other vegetable oils could also be used. The alkyd structure could be changed by formulation to have different functionality and the ability to incorporate higher amount of PET waste. Rate of glycolysis of PET could be increased by higher amount of ethylene glycol.

This method has managed to use waste PET in producing new polyol and PU resins. The cured films exhibit good mechanical and chemical properties, as well as excellent adhesion and thermal stability.

The non-biodegradable PET has created environmental pollution problems connected to littering and illegal landfilling. It has become necessary to pay greater attention to recycling PET bottles for obtaining valuable products.

This approach is different from the earlier reports, where PET was recycled to recover the raw materials.

Where does the coatings industry look for technology which borders on its own and from which it might derive useful leads and ideas? The coatings industry basically depends on the formation of films. Basic to the idea of coatings is the concept that there must be a film and that this film must derive from the vehicle in the coating. To be sure, the film does not represent the entire coating, but it is the sine qua non; and without a film the coating will neither decorate nor protect. There are a host of other technologies that depend on film formation. When the word ‘film’ is mentioned, adhesives and printing inks come to mind, for these technologies also could not exist without the all‐important phenomenon of film formation.

The electronics assembly industry has fortunately rediscovered conductive adhesives as the search for lead‐free joining materials and improved performance intensifies. Although these intrinsically clean bonding agents are often first sought for their favourable environmental attributes, many are surprised to find that conductive adhesives can solve old and new problems. Today, new polymer solders for SMT allow low temperature processing, finer pitch assembly and wider processing latitude while providing compatibility with a very much larger range of materials than solder. State‐of‐the‐art adhesives are oxide‐tolerant and absolutely no fluxing or cleaning is required. Adhesives work where solder cannot be used. What's more, polymer‐based solder alternatives can run on existing SMT lines — no new equipment is needed. Z‐axis, or anisotropic, bonding agents are uni‐directional conductive materials that solve fine pitch interconnect problems in several areas. The anisotropics now dominate the flat panel interconnect field. Nearly every LCD and other flat panel display is connected with a polymer adhesive. The Z‐axis adhesives are also beginning to enable high density multilayer circuits and MCMs to be built more effectively. Finally, Z‐axis appears to offer the simplest and most cost‐effective means for flip chip bonding. However, special equipment is required. The paper compares the metallurgical solder joint, the present de facto standard, with the polymer composite bond to highlight similarities and important differences. All types of conductive adhesives are discussed including the latest — Area Array Z‐axis types. Bonding materials, assembly processes and performance are also covered.