Poly (propylene carbonate) diol (PPCD) is one of the most attractive CO2 copolymers. PPCD‐based polyurethane has excellent mechanical properties and hydrophilicity, and is widely used in various ...fields. However, poor alkali resistance limits the application of PPCD‐based polyurethane in wet‐type artificial leather (WPL). In order to solve this problem, polyurethane solution (PUS) for wet‐type artificial leather was prepared by using PPCD and polytetramethylene ether glycol (PTMG) as soft segments. The chemical structure, viscosity, molecular weight and distribution, physical and mechanical properties, thermal properties and dynamic mechanical thermal properties of PUS were characterized. The changes of the physical and mechanical properties of PUS films and surface morphology of WPLs after soaking in 10 wt% NaOH solution at room temperature for 24 h were studied, so as to evaluate the alkali resistance of polyurethane. The retention of tensile strength and tearing strength of PUS films modified by PTMG increased from 80% to 96% and from 89% to 100%, respectively. The scanning electron microscopy results showed that appropriate PTMG was beneficial to the formation of microporous structure for CO2‐based polyurethane leather. The leather without PTMG showed agglomeration phenomenon, the micropores were not obvious, and the changes were obvious after soaking in alkali solution. After being modified by PTMG, the morphology of leather after soaking in alkali solution was basically unchanged. Polyurethane leather prepared with PTMG and PPCD as soft segments has excellent alkali resistance. These results suggest that PPCD could be a potential artificial leather material.
•The feasibility of pyrolysis in the disposal of PVC artificial leather was studied.•Strong synergistic effect during co-pyrolysis was observed and analyzed.•Tar yield reached 54.96% during ...co-pyrolysis of PVC and cloth at 500 °C.•PVC tended to react with cellulose and PET to form a stable compound in 420–500 °C.•The interaction mechanism with potential routes during co-pyrolysis was proposed.
With the massive production and discard of PVC artificial leather, it is urgently needed to find an efficient and environment-friendly method to dispose of this material made from PVC and blended cloth (BC). As a widely accepted way to dispose of municipal solid waste, pyrolysis was chosen for this study. The pyrolysis experiments of PVC, BC, and their mixture were conducted to characterize PVC artificial leather’s pyrolysis behavior and product characteristics. TG-FTIR and kinetics analysis showed the strong synergistic effect between PVC and cellulose in BC occurred at 240 °C – 314 °C, resulting in cellulose dehydration and aromatization. An exceptionally high tar yield of 54.96 wt% was obtained by fast pyrolysis of the mixture at 500 °C. GC–MS analysis of tar proved BC consisted of cellulose, PET, and PA. The high tar yield of co-pyrolysis came from the synergistic effects of PVC on cellulose and PET, both of which formed terephthalic acid, di(2-chloroethyl) ester (TADE). At 500 °C, the tar of the mixture mainly contained TADE (18.72 wt%), terephthalic acid (18.56 wt%), and aromatics (19.04 wt%). The co-pyrolysis interaction mechanism at 500 °C was deduced. Our study could provide theoretical guidance for recycling PVC artificial leather waste.
A type of polyester-based self-matting waterborne polyurethane (ESMWPU) with an excellent matte effect of 0.8° and transmittance of 78.5% for PVC artificial leather was synthesized. The influence of ...synthesis parameters, including R value, crosslinking and hydrophilic group content, on coating gloss and transmittance was investigated. Meanwhile, the properties necessary for applying water-based resins to plasticized PVC were detailed. The results demonstrated that R value, crosslinking degree and hydrophilic group content synergistically decided the morphological changes of latex particles during their film-forming process in three aspects: particle stiffness, three-dimensional structure and particle size, respectively. With optimized parameters of R = 1.9, TMP = 2 wt% and DMPA = 1.75 wt%, ESMWPU latex particles stabilized their spherical shapes without collapsing in the film-forming process and created a rough surface, resulting in a matte effect. In terms of application performance, good wetting and adhesion for ESMWPU to a plasticized PVC surface was achieved with a 2 wt% leveling agent load. Moreover, due to the high cohesion energy of ester bonds and intermolecular hydrogen bonds, this type of polyester-based ESMWPU also depicted admirable thermal adhesion resistance. All aforementioned results distinctly demonstrate a feasible yet promising paradigm for applying ESMWPU on PVC artificial leather.
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•The latest advances of polyurethane/graphene composites including their properties and challenges in the fields of thermal conduction and flame-retardance, antimicrobial, ultraviolet ...resistance, electromagnetic interference shielding, and oil–water separation are widely presented.•The preparation process, applications and prospects of the PU/graphene composites in high-performance synthetic leather are summarized in this review.•Functionalization of polyurethane and graphene nano-derivatives including covalent and noncovalent modifications of the composites are covered.•We put forward some novel speculations for the composites and their synthetic leather manufacture in advanced areas.
In recent years, polyurethane/graphene composites (PUGs) have attracted considerable attention attribute to their wide applications ranging from industrial manufacturing to bioengineering. The addition of graphene-based derivatives to the PU matrix can improve the mechanical, thermal, and electromagnetic properties, etc., to meet the specific demands of quality, functionality, and novelty of polymer composites. There are different modification methods of graphene and structural designs of polyurethane matrix for the applications of PUGs in various areas. Among the major applications, PUGs possess remarkable features in the dipping and coating process of synthetic leather. However, limited comprehensive summaries of functional PUGs have been published in broad fields and synthetic leather. The review aims to provide an overview of the cutting-edge developments of PUGs in the properties of thermal conduction and flame-retardance, antimicrobial, ultraviolet resistance, electromagnetic interference shielding, and oil–water separation respectively, which path a way for researchers to apply these uniquely functional composites for high-performance and advanced applications. And the applications of the PUGs in high-physical synthetic leather and the current challenges and prospects of synthetic leather in advanced fields are briefly presented.
Nishijin is famous for its traditional technique of cutting Japanese paper to a thickness of 0.2 to 0.3 mm and weaving it with warp and weft threads. This technique is called ‘hikibaku’. In the ...previous paper, we reported on the creation of a new textile with a new tactile feeling by using natural cowhide instead of Japanese paper used in hikibaku. In this paper, we describe the details of the automation of the hikibaku technique that created the new textile, and conduct a durability test of the newly produced textile using artificial leather, which is of stable quality, instead of natural cowhide, and discuss its new applications.
Leather is one of the most popular products across globe and holds a significant place in the economy, while the pollution, associated to traditional leather industry, is far away on the “green ...chemistry” principles. In this sense, polyurethanes, which exhibit tunable chemical structures by selecting suitable precursors, can fit specific requirements, and the developments of green strategies make them important candidates for leather industry. This mini review briefly outlines the recent development of conventional (petrol-based) and sustainable polyurethanes in the leather industry, including their design and properties, in applications such as synthetic leather and surface-finishing (coatings/binders). Finally, outlooks of the future tendency, including more environmental-friendly strategies, bio-sourced/recycled materials and development of high-value multifunctional leather materials, are also here proposed.
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Various interior non-metal materials contained in the automobiles, mainly such as textiles, synthetic textiles, leather, synthetic leather and foambased materials, are suitable for the production of ...sound and thermal insulation products. The presented contribution deals with the proposal of reusing and recycling ofthese components for the utilization ofthese non-metal materials for the production of new products, which, due to their sound and thermal insulation properties, will be widely applicable in various fields of industry as civil engineering, transport.
A type of high solid content waterborne polyurethane (HSWPU) dispersions applied to foamed artificial leathers were designed and prepared by prepolymer method. The solid content of the waterborne ...polyurethane dispersions could reach 53 %, and the foaming ratio could reach an astonishing 2.50 by adjusting the parameters. The influence of synthesis parameters, including R value (molar ratio of -NCO/-OH), D value (hydrophilic group content), trimethylol propane (TMP) content (degree of crosslinking) and ethylenediamine (EDA) content (it was chain extender) on foaming ratio were investigated. Meanwhile, a series of properties of HSWPU dispersions, films and foamed artificial leathers were introduced in detail. The results demonstrated that R value, TMP content, D value and EDA content synergistically decided the foaming properties of HSWPU dispersions in three aspects: three-dimensional structure, surface tension and polarity, respectively. With optimized parameters of R = 2.0, TMP = 0.4 wt%, DMPA = 3.0 wt% and EDA = 60 wt%, the HSWPU dispersions had good appearance and stability, and the latex particles exhibited excellent water, acid and alkali resistance after films formation. The HSWPU dispersions with high foaming rate without collapsing in the foam-forming process and created uniformly bubble pores. In terms of application properties, the prepared foamed artificial leathers showed admirable air permeability and water vapor transmissions. All results distinctly demonstrate a feasible yet promising paradigm for applying the HSWPU on foamed artificial leathers had great potential applications.
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•The solid content of the prepared waterborne polyurethane dispersions could reach 53 %, which greatly reduces the energy loss of packaging, transportation and practical application.•By combining mechanical and physical foaming with scraping and baking technology, a fluffy and porous structure of artificial leathers were realized.•By designing and synthesizing unique aromatic polyether waterborne polyurethane foaming resin, excellent performance at high foaming rate could be achieved.
Background: Authors of this article have made a comparative identificational description of artificial leather damage caused by air gun pistol pellets with different head end forms. Aim: This study ...aimed to provide a comparative identification characteristic of injuries caused by shots from an air pistol MP-53 M on artificial leather with a raised surface and a textile net glued to the wrong side at different angles and from different distances by bullets with different head end shapes (hemispherical, flat round, and conical). Used: Air pistol MP-53M, bullets with different head end shape, a fragment of black artificial leather with an embossed surface, and a textile mesh glued to the wrong side. Shots were fired at close range, 50 and 100 cm at angles of 30, 45, 60, and 90. The prevailing forms of damage (defects) of artificial skin, characteristic of bullets with a hemispherical, conical, and flat rounded head end, dependence of the form of damage (defect) on the distance of the shot, and the angle of entry of the bullet into the material. Conclusion: A comparative study showed that the form of damage to the material depends on the head end shape of bullets. Moreover, intragroup differences were found in the damage due to the distance of the shot and angle of entry of the bullet into the material in groups of bullets with the same head end shape.
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