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UV‐curable systems based on the copolymerisation of a typical acrylic resin with low amount of fluorinated monomers (less than 1 per cent w/w) were prepared. The bulk properties of the films were unchanged, while a strong modification of the surface was obtained, depending on the monomer structure, on its concentration and on the type of substrate.

New acrylic and allylic resins were prepared by functionalising perfluoropolyethers chains, which assured peculiar surface properties. Blends having a different amount of the acrylic and of the allylic systems were cured in air by UV irradiation. The cure of the films was found dependent on the ratio between the two resins; the concentration for the obtaining of a film fully cured in air was determined. On the basis of this concentration, a macromer functionalised with the right amount of both the acrylic group and the allylic one was synthesised.

The cotton and its blends is the most commonly used textile material in the design and production of protective clothing. However, as the cellulose textiles are the most flammable materials it is necessary to improve its flame retardancy. The government regulations have been the driving force for developing durable flame retardants finishes for textile, to improve its performance and to reduce the negative impact on the environment. The paper aims to discuss these issues.

This paper investigates the effect of silica precursor (tetraethoxysilane – TEOS) added in bath with conventional flame retardant urea/ammonium polyphosphate in full and half concentration for achieving environmental-friendly cotton flame retardancy. Silica precursors have excellent thermal stability and high heat resistance with very limited release of toxic gases during the thermal decomposition. Synergistic effect between urea/ammonium polyphosphate and TEOS has been calculated. Thermal properties of treated cotton fabrics were determined by limiting oxygen index (LOI), thermogravimetric analysis (TGA) and microscale combustion calorimeter (MCC).

TEOS, significantly improves the flame retardancy of cotton when added in the bath with conventional flame retardants urea/ammonium polyphosphate by increasing the LOI values and other thermal properties as increasing char residue measured by TGA and higher heat release rate measured by MCC.

This paper represent a good synergistic effect between urea/ammonium polyphosphate and TEOS. This phenomena is evident in better thermal properties when TEOS was added in the bath with conventional flame retardant especially for half concentration of urea/ammonium polyphosphate.

The purpose of this paper is to investigate the effect of char on the flame retardancy of fabrics by a cone calorimeter, which is an important factor to compare the flame retardancy of different fabrics.

Cone calorimeter measurements were carried out in a Fire Testing Technology (UK) apparatus at the heat fluxes of 50 and 75 kW/m². Fabrics with one and three layers were employed, with the name of cotton1, cotton3, FR cotton1, FR cotton3, PMIA1 and PMIA3. The dimension of the fabric was 100×100 mm². A cross-steel grid was used to prevent the fabrics from curling during burning. The distance between the bottom of the cone heater and the top of the sample was 25 mm.

This work was generously supported by National Key R&D Program of China (Project No. 2017YFB0309000), Natural Science Foundation of Shandong Province of China (Project No. ZR2019BEM026), Natural Science Foundation of China (Project No. 51803101) and China postdoctoral science foundation funded project (Project No. 2018M632619).

The present research provides insight into the effect of the char formation on the flame retardancy of the fabrics, and a method to comprehensively investigate the char influence in the flame retardancy of the fabrics by a cone calorimeter is proposed.

Achieving project performance goals in extremely resource-constrained environments, such as those of social enterprises, is challenging. These organizations often employ bricolage – making the most of available resources – to navigate challenging landscapes. This study aims to understand how bricolage capabilities enhance or attenuate organizational project outcomes in resource-constrained social enterprises.

An exploratory survey was conducted to understand project management practices in Canadian social enterprises. Established scales were used to measure constructs with confirmatory factor analysis, and linear regression was employed to analyze relationships.

The study provides empirical evidence of the positive influence of bricolage on organizational project performance, with a crossover interaction observed for moderators – entrepreneurial leadership and project management capabilities. While project capabilities strengthen the positive impact of bricolage capabilities on project performance, entrepreneurial leadership has the opposite effect.

The insights from this study offer an initial roadmap for project managers for effective resource acquisition and utilization through bricolage, ultimately enhancing project management effectiveness in resource-constrained environments.

Despite the crucial role of bricolage capabilities in resource-constrained environments, the project management literature has largely neglected this concept. It is unclear how organizations use bricolage to manage projects. This lack of understanding challenges organizations, hindering their ability to apply bricolage consistently and thoughtfully in managing projects. Our study provides a deeper understanding of how bricolage facilitates project performance and enriches our understanding of it as an effective resource mobilization strategy within social enterprises.

Because of the anisotropy of the process and the variability in the quality of printed parts, finite element analysis is not directly applicable to recycled materials manufactured using fused filament fabrication. The purpose of this study is to investigate the numerical-experimental mechanical behavior modeling of the recycled polymer, that is, recyclable polyethylene terephthalate (rPET), manufactured by a deposition FFF process under compressive stresses for new sustainable designs.

In all, 42 test specimens were manufactured and analyzed according to the ASTM D695-15 standards. Eight numerical analyzes were performed on a real design manufactured with rPET using Young's compression modulus from the experimental tests. Finally, eight additional experimental tests under uniaxial compression loads were performed on the real sustainable design for validating its mechanical behavior versus computational numerical tests.

As a result of the experimental tests, rPET behaves linearly until it reaches the elastic limit, along each manufacturing axis. The results of this study confirmed the design's structural safety by the load scenario and operating boundary conditions. Experimental and numerical results show a difference of 0.001–0.024 mm, allowing for the rPET to be configured as isotropic in numerical simulation software without having to modify its material modeling equations.

The results obtained are of great help to industry, designers and researchers because they validate the use of recycled rPET for the ecological production of real-sustainable products using MEX technology under compressive stress and its configuration for numerical simulations. Major design companies are now using recycled plastic materials in their high-end designs.

Validation results have been presented on test specimens and real items, comparing experimental material configuration values with numerical results. Specifically, to the best of the authors’ knowledge, no industrial or scientific work has been conducted with rPET subjected to uniaxial compression loads for characterizing experimentally and numerically the material using these results for validating a real case of a sustainable industrial product.

PET fiber is widely used in many fields, such as clothing and decorative materials. However, the high flammability and dripping problem restrict its applications. It is vital for PET fiber to overcome these two main drawbacks for practical applications.

In this paper nacre-mimetic flame retardant coating of chitosan (CH) and Montmorillonite (MMT) was fabricated on PET fabrics through the layer-by-layer assembly method. The flame retardancy and anti-dripping performance of the treated PET fabric were investigated.

The results of limiting oxygen index (LOI) value and vertical burning test revealed the anti-dripping performance of PET fabrics which was greatly improved, while the flame retardancy has not been improved. The dripping phenomena was eliminated when the CH/MMT bilayers were over 5 BL. Thermo gravimetric analysis (TGA) results revealed that nacre-mimetic coated CH/MMT bilayers on PET fabrics would promote the char formation both under nitrogen atmosphere and under air atmosphere indicating the obviously condensed phase flame retardant action. scanning electron microscopy (SEM) images of the char residues revealed that coated PET fabrics would promote the formation of char.

However, the char was an unstable char which would further combust to change the thermal degradation and combustion process of PET fabric. Though PET fabric coated by this CH/MMT nacre-mimetic system had no flame retardancy, the anti-dripping performance was greatly improved. This research would provide experimental basis for improving the anti-dripping performance for thermoplastic materials.

This research is the original research for the flame retardant treatment by fabrication nacre-mimetic CH/MMT coating on PET fabric, which has not been reported previously. This research would provide experimental basis for improving the anti-dripping performance for thermoplastic polymer fabrics.

The purpose of this paper is to investigate the potential use of the layer-by-layer (LbL) assembly as an intumescent flame retardant for polyester, cotton and their blended fabrics.

In this study, polyester (PET), cotton and their blends were applied with the flame retardant coating via the LbL assembly technique. The flame retardancy, melt dripping, thermal properties and morphology of coated polyester fabrics were then examined.

The scanning electron micrograph of uncoated and coated fabrics revealed that the LbL assembly coating on the fabric surface was successful. The assessment of the flame retardancy and thermal properties of the coated fabrics showed that the after-flame time and melt dripping during the vertical burning test decreased. The char residue at temperatures ranging from 450 to 800°C during thermogravimetric analysis was enhanced as compared with the uncoated fabric. Furthermore, the morphology of the char residual of coated fabrics was rougher and bulkier than the uncoated fabrics, suggesting the typical behavior of intumescence.

The LbL technique generally uses much fewer chemicals, thus making this flame retardant finishing much more environmentally friendly. It is also expected that these fabrics will show better touch characteristics. These fabrics may be tested for their comfort compared to that of conventional coating to enable their use on an industrial scale.

This work demonstrated the ability to apply an effective intumescent coating on polyester, cotton and blend fabric. In order to maintain fabric handle property, the Lbl coating technique is also employed.

Agile project management methods are on the rise compared to linear approaches. The demand for the demonstrable resilience of enterprise processes is likewise strongly increasing in many domains. This paper explores the potential contribution of agility within the domain of agile project management to the resilience of the operating model of an organization.

The article builds upon case studies and semi-structured interviews at selected larger Danish enterprises.

Responding to disruptions favors adaptive and flexible approaches, which are more achievable with agile methods. By exploring the patterns of agility and resilience throughout case studies, the authors derive at a 7-step approach for considering the potentials of agility to ensure the resilience of the operating model from the top level of leadership to the foundational level of technology.

This article seeks to contribute to a more profound understanding of the impact, potential and actionability of agile project management in the light of operational resilience.

It is demonstrated that agile methods are attractive for ensuring the constitutive elements of the resilience of the operating model in terms of conscious contingencies and choices involving (rapid) changes.

During the COVID-19 period, agility has been a key instrument in ensuring business survival, e.g. by switching markets, products or sales channels.

Agility has the potential to build a strategic dimension of resilience, a synergistic relationship, which is linked to the responsiveness of an organization to change promptly, with a view toward renewal and transformation.

The purpose of this paper is to investigate the effects of multi-hydroxymethylated phenol (MHMP) on the properties of moisture-curing polyurethane (PU) resin, especially on the heat resistance.

The MHMPs with various active sites from 2.52 to 3.91 were synthesised and used as a modifier. The bond test (according to the JIS K6806-2003 standard) and thermogravimetric analysis (TGA) were used, respectively, to characterise the bond durability and heat resistance of MHMP-modified PU resin.

The MHMP with various F/P mole ratios had great effects on the properties of resultant PU resins. The increase of active sites of MHMP can improve the water resistance of resin due to the more cross-linking densities, while the decrease of active sites of MHMP can improve heat resistance of resin because more stable benzene ring introduced into the PU backbone.

In cases where heat resistance of the PU resin is of primary concern, the use of MHMP with fewer active sites or a lower F/P ratio is recommended. In other cases where bond durability is focussed, the modifier MHMP shall be synthesised with higher F/P ratio.

MHMP as a modifier can be used to improve the heat resistance of PU resin.

The MHMPs with various hydroxymethyl groups were synthesised and used as modifier of moisture-curing PU resins to improve their heat resistance.