Synthesis and swelling behaviors of sodium carboxymethyl cellulose-g-poly(AA-co-AM-co-AMPS)/MMT superabsorbent hydrogel

Enhancement of chromium uptake in tanning process of goat garment leather using nanocomposite

Recently, increasing interests have been directed towards incorporating nanotechnologies into leather manufacturing, which offer cost-effective improvements in leather performances, as well as enabling the industry to meet stricter legislation regarding environmental safety In order to guide the leather technologists and chemists worldwide, this article reviews state of the art related to existing nanotechnologies in leather manufacturing processes, including tanning, finishing and effluent treatment, over the past decade The emphasis is placed on the mechanism by which nanotechnologies improve conventional processes, impressive performances of the resultant leather and possible obstacles that cloud technical development in this field In the end, potential health and environment risks associated with the incorporation of nanotechnologies, which are particularly important for daily necessities such as leather but have been basically overlooked by many researchers involved, are also addressed RESUMENUltimamente ha habido un gran interes por introducir nanotecnologias a la curticion del cuero Estas tecnologias ofrecen mejoras en el desempeno del cuero a costos favorables, asi como permiten a la industria el cumplimiento de normas legales mas estrictas en la seguridad medio-ambiental Para poder guiar a los tecnologos y quimicos del cuero mundialmente, este articulo pasa revista al estado mas avanzado en relacion a nanotecnologias ya existentes en los procesos de fabricacion, incluyendo el curtido, acabado, y el tratamiento de efluentes durante la ultima decada El enfasis es dirigido hacia el mecanismo por medio del cual nanotecnologias mejoran los procesos convencionales, los impresionantes logros alcanzados en el desempeno del cuero en que resulta, asi como los posibles obstaculos que opacan los desarrollos tecnicos en el ramo Finalmente, los riesgos medioambientales y potenciales a la salud, asociados con la incorporacion de nanotecnologias, son particularmente importantes para cumplir con las necesidades cotidianas, tal como lo es el cuero, pero han sido basicamente ignoradas por los muchos investigadores involucrados, tambien son examinados

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Nanotechnologies for Leather Manufacturing: A review

Understanding accessibility and interactions of clay nanoparticles with collagen fibers is an important fundamental issue for the conversion of collagen to leather matrix. In this study, we have investigated the diffusion and binding of Laponite into the collagen fiber network. Our results indicate that the diffusion behaviors of Laponite into the collagen exhibit the Langmuir adsorption, verifying its affinity for collagen. The introduction of Laponite leads to a shift in the isoelectric point of collagen from ∼6.8 to ∼4.5, indicating the ionic bonding between the positively charged amino groups of the collagen and negatively charged Laponite under the tanning conditions. Fluorescence microscopy, atomic force microscopy, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and wide-angle X-ray diffraction analyses reveal that Laponite nanoparticles can penetrate into collagen microstructure and evenly distributed onto collagen fibrils, not altering native D-periodic banding ...

Diffusion and Binding of Laponite Clay Nanoparticles into Collagen Fibers for the Formation of Leather Matrix.

Facile preparation approach of nanocomposite based on water-soluble polymer and layered double hydroxides for the enhancement of leather dyeing

Acrylic resin/montmorillonite (AR/MMT) nanocomposite was prepared using Na+-montmorillonite (Na+-MMT) via in-situ polymerization of hydrophilic monomer in aqueous medium. The synthetic conditions, such as the contents of MMT and ammonium persulfate (APS), the molar ratio of different monomers, and the dosage of sodium bisulfate on the application properties of nanocomposite were investigated in detail. The thickness increment ratio, the wet-heat resistance and the tensile, slit and burst strengths of leather tanned by AR/MMT were improved and elongations at break and given load were slightly reduced, in contrast to AR treatment; the wet-heat resistance and the physical / mechanical properties of leather tanned by 6% AR/MMT associated with 2% chromate were lower than 8% chromate tanned. As well, AR/MMT facilitates the absorption of chromate. Compared with conventional chrome tanning, the dosage of chromate is reduced 75%. Scanning Electron Microscope (SEM) pictures of leather samples indicated that the collagen fiber of leather samples tanned by AR/MMT was well dispersed when compared to AR and pure chromate treatment. X-ray Diffraction (XRD) and Transmission Electron Microscope (TEM) confirmed AR/MMT is an exfoliated nanocomposite. RESUMENLa nanopreparacion de resina acrilica/montmorillonita (AR/MMT) fue preparada in situ con Na+-montmorillonita (Na+-MMT) a traves de la polimerizacion del monomero hidrofilo en medio acuoso. Las condiciones de la sintesis, tal como el contenido de MMT y persulfato de amonio (APS), la relacion molar de los diferentes monomeros, y la dosis de bisulfato de sodio, sobre la aplicacion de las propiedades de la nanopreparacion fueron investigadas en detalle. La proporcion del incremento de espesor, la resistencia al calor en humedo y la resistencia a la traccion, tension de corte y ruptura del cuero curtido con AR/MMT se han mejorado y elongaciones a la rotura y carga dada se redujeron ligeramente, en contraste con el tratamiento con AR; la resistencia al calor humedo y las propiedades fisico/mecanicas de los cueros curtidos con un 6% AR/MMT asociados con un 2% de cromato fueron inferiores a los curtidos con 8% de cromato. Ademas, AR/MMT facilita la absorcion de cromato. Comparado con el curtido al cromo convencional, la dosis de cromato se reduce en un 75%. Fotos de muestras de piel obtenidas mediante un microscopio electronico de barrido (SEM) indican que la fibra de colageno de las muestras de piel curtida por AR/MMT estaba bien dispersa en comparacion con las tratadas con AR y cromato puro. Difraccion de Rayos X (XRD) y Microscopia Electronica de Transmision (TEM) confirmaron que AR/MMT es un nanoproducto exfoliado.

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Preparation of acrylic resin/ montmorillonite nanocomposite for leather tanning agent

The invention relates to a preparation method for a leather tanning agent, in particular to a preparation method for a leather tanning agent with function of strengthening and toughening collagenous fibers The leather tanning process is a qualitative change process converting raw hide into leather, and can endow the leather with good heat and humidity resistant stability, flexibility and physical and mechanical properties; however, a chrome tanning agent commonly adopted has serious harm to the environment, while a conventional non-chrome tanning agent is hard to meet the requirement on good service performance of the leather The preparation method takes montmorillonite and acrylic monomers as raw materials, and adopts a monomer in-situ intercalation polymerization method to synthesize the toughening type leather tanning agent; and the toughening type leather tanning agent is used for tanning the leather, can greatly improve the strength and toughness of crust leather, and can reduce the dosage of the chrome tanning agent by 75 percent

Yan Bao

Papers

Preparation of acrylic resin/ montmorillonite nanocomposite for leather tanning agent

Preparation method for toughening type leather tanning agent