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In this work, a biologically active curcumin molecule is used as an antibacterial agent, and the insertion of this naturally occurring biomolecule into the backbone of water-dispersible polyurethane has been successfully achieved to synthesize bio-based antibacterial textile finishes. These curcumin-based water-dispersible polyurethane (CUR-WDPU) dispersions were prepared by utilizing isophorone diisocyanate (IPDI), polyethylene glycol (PEG), dimethylolpropionic acid (DMPA) and triethylamine (TEA) following the prepolymer mixing process by incorporating variable molar quantities of curcumin (CUR). Structure elucidation of synthesized CUR-WDPU dispersions was obtained through Fourier transformed infrared spectroscopy (FTIR) which confirmed the insertion of CUR into the WDPU backbone. Using the pad-dry-cure procedure, the varying varieties of plain weave polyester/cotton blended dyed and printed textile samples were treated with synthesized CUR-WDPU finishes. The antibacterial activities of these treated textiles have been assessed, and the outcomes revealed that the insertion of curcumin into the PU polymer chain has significantly boosted the antibacterial activities of PU dispersions. These newly prepared CUR-WDPUs dispersions are proved to be eco-friendly antimicrobial finishes because these are containing natural bioactive agents such as curcumin, showing potential antibacterial applications on polyester/cotton textiles. Predominantly, this research work is an attempt toward the greener approach of novel bio-based finishing materials preferably useful for textile diligences. Future investigations of these finishes will explore the other textile assets of poly-cotton textiles without adversely influencing their color fastness and mechanical properties. [ABSTRACT FROM AUTHOR]

A series of polyurethane elastomers (PUEs) were prepared by the reaction of hydroxyl-terminated polybutadiene (HTPB) and toluene diisocyanate (TDI), the resultant PU prepolymer was extended with polydimethyl siloxane (PDMS). The conventional spectroscopic characterization of the synthesized samples using Fourier transform infrared spectrophotometer confirmed the structure of the proposed PDMS-based PU. Thermogravimetric analysis (TGA) was carried out to determine the thermal stability of the prepared PU samples. Surface properties of the synthesized material were studied determining the percentage of water absorption and equilibrium degree of swelling. The results revealed that by increasing the mole ratio of PDMS, the synthesized PUEs showed hydrophilic behavior while placing them in water and dimethyl sulfoxide solvent. [ABSTRACT FROM AUTHOR]

The effect of structural chemistry of different soft segments on various structural properties of polyurethane-urea (PUU) elastomers was evaluated in this study. A series of PUU elastomers were prepared by the reaction of 4,4'-diisocyanato dicylohexylmethane (H12MDI) with polycaprolactone (PCL), Polytetramethylene glycol (PTMG), Polyethylene glycol (PEG), Polybutylene adipate (PBA) and amine chain extender 4,4'-methylenebis(2,6-diethylaniline) (MBDEA). Fourier transform infrared (FTIR) spectroscopy was used to study the synthesis of final PUU elastomers. Thermal behaviour of PUU elastomers was investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis. The surface properties and hardness of elastomers were characterized by measuring contact angle and hardness in shore A scale. The results showed highest thermal stability and hydrophobicity of PUPCL i.e., Polycaprolactone polyol based PUU elastomer. The proposed synthesis of PUU elastomers was confirmed by the appearance of -NH peak at 3305-3315 cm-1 and disappearance of -NCO peak at 2270 cm-1 in FTIR spectra. [ABSTRACT FROM AUTHOR]

ABSTRACT We prepared and then blended polyurethanes (PUs) with poly(methyl methacrylate)s (PMMAs) and TiO2 by varying the percentage compositions to form pellets. The chemistry of all of the blended samples was confirmed by Fourier transform infrared spectroscopy. The incorporation of TiO2 into the PU-PMMA matrix was confirmed with scanning electron microscopy analysis. Differential scanning calorimetry analysis and compression testing was performed, and the results are discussed. The cytotoxicity level of the prepared blends displayed dependence on the composition ratio of the PU-PMMA blends. The results reveal that the optimum PU contents in the PU-PMMA-TiO2 blend were responsible for its better biocompatibility. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39806. [ABSTRACT FROM AUTHOR]

Abstract: Polyurethane acrylate copolymers (PACs) were synthesized by three step synthesis process via emulsion polymerization using toluene-2,4-diisocyanate, hydroxy terminated poly (caprolactone) diol (PCL), 2-hydroxyethylacrylate (HEA) and butyl acrylate (BuA). The proposed structure of the synthesized polyurethane acrylate copolymer (PAC) was confirmed using Fourier transform infrared (FTIR) spectrophotometer. The pilling characteristic and antimicrobial activities of the plain weave poly-cotton grey, white, printed and dyed fabric swatches after application of PAC were evaluated. The results revealed that by increasing the molecular weight of PCL in the synthesized PAC samples, the antimicrobial activities increased and this behavior was interpreted in term of increasing hydrophilic character. An increase in pilling ratings of the treated samples has been observed by increasing the molecular weight of the polycaprolactone diols in the synthesized PAC samples. [Copyright &y& Elsevier]

Abstract: A series of aqueous solutions of poly(vinyl alcohol) of various commercial products were prepared and applied onto the surfaces of cotton and blends of cotton/polyester fabrics. Fourier transform infrared spectrophotometer was used to confirm the molecular structure of the polyvinyl alcohol used. Performance tests such as colorfastness to rubbing (dry and wet) and colorfastness to washing were determined. The controlling variables affecting the performance properties of the finished substrate such as post-treatment with poly(vinyl alcohol) of various commercial trades, concentration and dilutions were studied. Crocking, washing and hue change of the treated dyed and printed fabrics is accompanied by the formation of semi-inter-penetrated network structure due to the presence of the hydroxyl (–OH) groups which make feasible to a number of grafting and physical cross linking reactions of polymer backbone. [Copyright &y& Elsevier]

In this study, we evaluated the morphological behavior of polyurethane elastomers (PUEs) by modifying the soft segment chain length. This was achieved by increasing the soft segment molecular weight (Mn = 400–4000 gmol−1). In this regard, polycaprolactone diol (PCL) was selected as the soft segment, and 4,4′-cyclohexamethylene diisocyanate (H12MDI) and 1,6-hexanediol (HDO) were chosen as the hard segments. The films were prepared by curing polymer on Teflon surfaces. Fourier transform infrared spectroscopy (FTIR) was utilized for functional group identification in the prepared elastomers. FTIR peaks indicated the disappearance of −NCO and −OH groups and the formation of urethane (NHCOO) groups. The morphological behavior of the synthesized polymer samples was also elucidated using scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. The AFM and SEM results indicated that the extent of microphase separation was enhanced by an increase in the molecular weight of PCL. The phase separation and degree of crystallinity of the soft and hard segments were described using X-ray diffraction (XRD). It was observed that the degree of crystallinity of the synthesized polymers increased with an increase in the soft segment's chain length. To evaluate hydrophilicity/hydrophobicity, the contact angle was measured. A gradual increase in the contact angle with distilled water and diiodomethane (38.6°–54.9°) test liquids was observed. Moreover, the decrease in surface energy (46.95–24.45 mN/m) was also found to be inconsistent by increasing the molecular weight of polyols. [ABSTRACT FROM AUTHOR]

The present study describes a novel ecofriendly series of chitin/curcumin/1,4-butane diol (BDO) blend derived polyurethanes (PUs), using hydroxy terminated polybutadiene (HTPB) and hexamethylene diisocyanate (HDI) along with different mole ratio of chitin, curcumin and BDO. The structural and morphological elucidation of the prepared films was done by FTIR and SEM techniques. The swelling behavior of the films was analyzed in both water and DMSO, which showed that incorporation of chitin increases the hydrophobicity and decreases the rate of swelling. Thermal analysis of synthesized PU blends revealed better thermal stability with following mole ratio 1:0.5:0.5 of chitin: curcumin: BDO as determined by TGA and DSC techniques. [ABSTRACT FROM AUTHOR]

Highlights: [•] New chitosan based polyurethane elastomers (PUEs) were synthesized. [•] Molecular engineering was carried out during the synthesis using FT-IR. [•] The FT-IR confirms the existence of the proposed chitosan based PUEs structure. [•] Internal morphology of the prepared PUEs was studied using SEM analysis. [ABSTRACT FROM AUTHOR]

Abstract: Chitin based polyurethanes (PUs) using hydroxyl terminated polybutadiene (HTPB) as soft segment were prepared and the structure of the proposed PU was confirmed using FTIR spectrometer. PU prepolymer was prepared using HTPB and toluene-2,4-diisocyanate (TDI), and the chain was extended with different proportions of 1,4-butane diol (BDO) and chitin. During the detailed FTIR study, it was observed that tri-functional character of chitin results in the formation of network structure due to crosslinking of the material, whereas bi-functional aliphatic diol based polyurethane produced linear PU. Hydrogen bonding between the hard segments was identified by the IR spectroscopy. The scanning electron microscope (SEM) analysis also confirmed the cross-linked structure. [Copyright &y& Elsevier]

Abstract: Polyurethane acrylate (PUA) copolymers were synthesized following three step synthesis using toluene-2,4-diisocyanate, poly (2-methyl-1,3-propylene glutarate) diol terminated, 2-hydroxyethylacrylate (HEA) and butyl acrylate (BuA) via emulsion polymerization technique. The conventional spectroscopic characterization of the samples with FT-IR was in accordance with proposed PUA copolymer structure. The synthesized PUA copolymer samples were applied using dip-padding techniques on mill desized, scoured, bleached, printed, 100% cotton combed satin, striped weave fabrics. The emulsion stability evaluation and pilling rating showed reciprocal dependence on the percentage of butyl acrylate (BuA) and dual dependence on the concentration of vinyl terminated polyurethane prepolymer. The results revealed that by decreasing the mole ratio of polyol the emulsion stability and pilling rating drastically increased. [Copyright &y& Elsevier]

Abstract: This article is aimed to discuss the modification of guar gum through microwave irradiation by varying the time of irradiation. The characterization of the modified products was carried out using FTIR spectroscopic analysis. The FT-IR spectrum of the pure guar gum (GG) sample showed a broad peak at 3298cm−1 while the modified GG sample displayed a peak at 1541cm−1 which was absent in the crude sample. The X-ray diffraction (XRD) analysis confirmed the increase in crystallinity due to grafting of the sample with polyacrylamide (GG-g-PAM). Scanning electron microscope (SEM) images revealed that granular form of guar gum was changed into fibrillar structure after grafting. Thermo-gravimetric analysis of the modified samples was also carried out and discussed. The role of guar gum as a matrix for controlled release of drug triamcinolone was evaluated. The GG-acrylamide grafted samples presented a correlation between drug release and time of microwave exposure. The results revealed that such modified product has potential applications in colonic drug delivery system. [Copyright &y& Elsevier]

Highlights: [•] Chitin based polyurethane (PU) using (HTPB) was prepared. [•] The FT-IR analysis confirmed the crosslinking behavior of the material [•] The SEM images also confirmed the cross-linked and non-cross-linked structure. [•] EDX–SEM analysis also supported the FT-IR and SEM analysis. [Copyright &y& Elsevier]

Abstract: Hetero-polysaccharide mucilage was extracted from the seed coats of different citrus rootstocks viz. Rough lemon, Sachtion citrumelo and Yuma citrange for investigating its biochemical and molecular properties. Investigations showed that the mucilage contained (mg/g) starch 3.13–5.04; maltose 3.23–4.31; glucosamine 0.017–0.289; d-xylose 0.059–0.107 and total soluble sugars 8.13–11.82. Specific enzyme activities were 16.98–35.96, 30.60–98.45, 42.00–73.98, 660.98–738.35 and 7.660–19.27IUmg−1 of protein for protease, amylase, catalase, peroxidase and superoxide dismutase, respectively. Proximate analysis showed 12.85–13.94% moisture, 11.25–14.06% crude protein, 0.31–0.86% crude lipid, 1.31–2.69% crude fibre, 2.95–3.45% ash and 81.48–91.49kJ 100g−1 energy. The comparative characterization of the extractable proteins was profiled by SDS-PAGE and quantified using Bradford assay. Structural properties of samples were analyzed and compared using Fourier transformation infrared (FT-IR) spectroscopy. [ABSTRACT FROM AUTHOR]