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2-Hydroxyethyl cellulose graft polylactic acid copolymer (HLAC) was prepared by graft copolymerization of lactic acid (LA) and 2-hydroxyethyl cellulose (2-HEC), initiated by dibutyltin dilaurate (DBTDL) catalyst in aqueous media. Halloysite nanotubes (HNTs)/polyurethane (PU) bionanocomposites were prepared using the HLAC as chain extender in the step-growth polymerization. HNTs were dispersed in HLAC based PU matrix at different weight ratios of 0.30, 0.50, 1.00, and 3.00. Chemical structure and morphology of the graft copolymer and bionanocomposite elastomers were characterized using solid state 1H NMR, ATR-FTIR, XRD, and SEM-EDX, while thermal degradation behavior was studied by TGA and DSC techniques. Surface morphology of the HNTs reinforced HLAC/PU bio-nanocomposites demonstrated the homogeneous dispersion of HNTs with little wavy rough surface at low contents which turned to be brittle at higher contents due to agglomerated HNTs. It is observed that the lower contents of HNTs were completely exfoliated in the HLAC/PU matrix. Crystalline pattern of the elastomers improved at lower contents of HNTs that enhanced the thermal stability of the bionanocomposites. The mechanical testing suggested that HNTs/HLAC/PU bionanocomposites have higher values of tensile strength and % elongation with only 0.3–0.5 wt% contents of HNTs that suggested the potential applications of elastomers at economic cost.

Starch/chitosan modified polyurethanes (PUs) were synthesized by step growth polymerization reaction between −NCO terminated prepolymer and chain extenders (1,4-Butanediol/starch/chitosan). Isophorone diisocyanate (IPDI) was reacted with hydroxyl-terminated polybutadiene (HTPB) to synthesize prepolymer and was further reacted with different moles ratio of starch/chitosan to produced five samples of polyurethane (PU). These samples were characterized by Fourier transformed infrared (FTIR) and Proton nuclear magnetic resonance (1H NMR) spectroscopy. The surface characterizations of PUs were done by scanning electron microscope (SEM). Thermogravimetric analysis showed that the thermal stability of PUs was higher when the mixture of both natural materials was used at equal amounts. It is concluded that combination of both starch and chitosan are efficient for the synthesis of PUs.

Waxy corn starch modified polyurethane elastomers were synthesized by step growth polymerization reaction between NCO-terminated prepolymer and chain extenders (1,4-butanediol/starch). Isophorone diisocyanates (IPDI) was reacted with hydroxyl terminated polybutadiene (HTPB) to synthesize prepolymer that was reacted with different moles of 1,4-butanediol (1,4-BDO) and starch to produced five samples of polyurethane. These specimens were analyzed by Fourier transformed infrared (FTIR) and proton Nuclear Magnetic Resonance (1H NMR) spectroscopy to determine the structural information. However, role of starch as chain extender was examined by gel permeation chromatography (GPC). Additionally, starch increased the thermal stability of PUs as compared to the conventional chain extender (1,4-BDO). Over all, this work has been designed to develop biodegradable polyurethanes that could be used in biomedical systems.

The preparation of amino silicone based softeners with different emulsifiers was carried out and adsorbed onto the surfaces of cotton and blends of cotton/polyester fabrics. The softened fabrics have high surface area, so poorly performance in washing and rubbing fastness. It is obvious from the results of colorfastness to rubbing and washing that some of the samples of the dyed fabric treated with prepared softeners have shown some poor rating as compared to the untreated fabrics. However the other two samples have shown acceptable rubbing fastness results without losing softness and permanent handle. It can be observed that washing of the printed treated fabric remains unaffected almost in all the studied samples. Moreover, the application of the prepared softeners has imparted anti pilling property to the fabric. It can be seen that there is a remarkable increase in weights of treated fabrics as compared to the untreated fabrics.