Polyester fiber is a manufactured fiber composed of synthetic linear macromolecules in the chain at least 85% by mass of an ester of diol and benzene-1, 4-dicarboxylic acid (terephthalic acid). Fibers of the most common polyester, poly(ethylene terephthalate) (PET or PET), are generally made from either terephthalic acid or dimethyl terephthalate together with ethylene glycol. Dyeing of polyester fabric with disperse dyes, polyester requires the use of dispersing agents. The chemical characteristics and general application conditions of disperse dyes are characterized by the absence of solubilizing groups and low molecular weight. Dye particles have a size ranging from 0.5 to 2.0 microns, generally contain –NH2, substituted –NH2, or –OH groups in the structure, and get attached with the fiber through H-bond and van der Waals force. Dyes are retained by the fiber by physical forces. Fastness properties are very high in polyester except in certain cases. The dye-fiber (PET) affinity is the result of different types of interactions, such as hydrogen bonds, dipole-dipole interactions, and van der Waals forces.

Natural organic fibers such as cotton, linen, and wool are readily attacked by microorganisms. Microbial growth on a textile fabric causes loss of strength and elongation, discoloration, and changes in appearance. The antibacterial finishing agents extracted from nettle plant leaf have been used to impart finish to the cotton fabric by using the Pad-Dry-Cure application method. The antibacterial activity of the finish was assessed quantitatively using the AATCC 100:2004 test method, and the antibacterial activity against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria was measured. There was a 100 to 99.75 percent reduction in the count of test bacteria. Physical properties of treated and untreated cotton fabrics such as absorbency, fabric stiffness, air permeability, and strength were analyzed. To evaluate the laundering effect of stinging nettle leaf finished fabric, samples were subjected to laundry with 5, 10, 15, 20, 25, 30, 35, and 40 washing cycles using standard AATCC test method 61, and bacterial count of treated samples was tested. The results showed gradual decrease in antibacterial property, with a 100 to 44% reduction in the bacterial count for Staphylococcus aureus and a 100 to 30% reduction in the bacterial count for Escherichia coli. The results of this investigation suggested that nettle leaf, a low-cost abundant plant in Ethiopia, can be used for antibacterial activity in woven cotton fabric.

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Copolymers of ethylene and 1-butene were synthesized using a single-site zirconium-based coordination catalyst. The polymers terminated exclusively in 1-butene ends, predominantly ethylvinylidene. They were carbonylated under Koch−Haaf conditions using boron trifluoride, carbon monoxide, and phenols to give polymeric hydrocarbons containing a single carboaryloxy group. Both 1,3- and 1,5-rearrangements were observed in this synthesis. The amination reaction with polyethylene amines followed second-order kinetics, but with a steadily decreasing bimolecular rate constant. The physical properties along with the block composition of the resulting polyhydrocarbon polyamine make this a potential candidate for motor oil dispersant. To interpret the polymer results, appropriate model compounds consisting of appropriately branched carboxylic acids, aryl esters, and amides were synthesized. The 13C NMR and IR spectra, both of the quaternary carbons and the carbonyls, supported the structure assignment for the polymers. Finally, the kinetics of the reactions of the model esters with model monoamines N,N-dimethyltrimethylenediamine and N-2-(ethylamino)piperidine quantitatively reproduced the amidation kinetics observed for the polymeric ester.

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