Dyeing of Polypropylene Fibers with Vat Dyes

Polypropylene fibers have been extensively used in a variety of/products, including carpets and upholstery, due to their non-absorbency, good weather resistance, good resistance to macroorgamsms and so on. Because of their hydrophobic and highly crystalline nature, those well-established conventionai dyeing processes are difficult to apply to unmodified polypropylene. Colors of polypropylene fibers are primarily obtained by mass coloration which has the disadvantages of limited number of colors available and difficulties in inventory control due to the rapidly changing color needs of the market. In this paper, the use of vat dyes to dye polypropylene fabrics is investigated. Seventeen vat dyes were screened and factors influencing uptake of dyes by polypropylene fabrics were studied.

A stable anthraquinone-derivative cathode to develop sodium metal batteries: The role of ammoniates as electrolytes

Rechargeable sodium metal batteries constitute a cost-effective option for energy storage although sodium shows some drawbacks in terms of reactivity with organic solvents and dendritic growth.Here we demonstrate that an organic dye,indanthrone blue,behaves as an efficient cathode material for the development of secondary sodium metal batteries when combined with novel inorganic electrolytes.These electrolytes are ammonia solvates,known as liquid ammoniates,which can be formulated as NaI·3.3NH_(3) and NaBF_(4)·2.5NH_(3).They impart excellent stability to sodium metal,and they favor sodium non-dendritic growth linked to their exceedingly high sodium ion concentration.This advantage is complemented by a high specific conductivity.The battery described here can last hundreds of cycles at 10 C while keeping a Coulombic efficiency of 99%from the first cycle.Because of the high capacity of the cathode and the superior physicochemical properties of the electrolytes,the battery can reach a specific energy value as high as 210 W h kgIB^(-1),and a high specific power of 2.2 kW kgIB^(-1),even at below room temperature(4℃).Importantly,the battery is based on abundant and cost-effective materials,bearing promise for its application in large-scale energy storage.

Effects of Treating with Laccase on Properties of Dyed Cotton Fabric

A laccase （Denilite IIS） was used to treat different cotton fabrics dyed with 0.2 g · L^-1 of vat dyes or reactive dyes. The results indicated that the laccase could remove the loosely adhering, unfixed or hydrolyzed dyes from the dyed fabric efficiently, which led to obvious improvements of color fastness. Furthermore, the wavelength of maximum absorbance of the residual solution of dyeing laccase-treated was different from that of the detergent-treated, which implied the laccase could accelerate structural changes of the adhering or hydrolyzed dyes from fabric in treating, resulting in obvious color changes of the residual solution. In addition, excessive laccase also could decolorize a few fixed reactive dyes from the dyed fabric, with a decrease of color strength and less further improvements of color fastness.