Preparation and Characterization of Aqueous Polyurethane Dispersions Derived from Anionic Polyester Diols

Aqueous polyurethane (APU) dispersions with improved hydrophilicity were presented and characterized. In order to make APU products more competitive, anionic diols and dimethylopropanic acid (DMPA) were introduced into the macromoleculars of APU. The particle sizes of the APU dispersions have been reduced from 0.7~3μm to 0.05~0.6μm, and the storage stability has been prolonged from 6 months to 12 months. It is efficient to prepare the self-emulsifiable APU dispersions by applying anionic polyester diols and using triethanolamine (TEOA) as a neutralization agent.

Preparation and characterization of aqueous polyurethane dispersions with well-defined soft segments

Journal of Applied Polymer Science ◽

10.1002/app.34095 ◽

2011 ◽

Vol 122 (5) ◽

pp. 3064-3070 ◽

Cited By ~ 17

Author(s):

Qunchao Zhang ◽

Jiankun Hu ◽

Shuling Gong

Keyword(s):

Soft Segments ◽

Preparation and Characterization of Aqueous Oil-Modified Polyurethane

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.239-242.1665 ◽

2011 ◽

Vol 239-242 ◽

pp. 1665-1669

Author(s):

Xiao Qi Chen ◽

Chen Bo Wu ◽

Zhao Jun Xue ◽

Yao Zong Geng ◽

Ji Jun Xiao

Keyword(s):

Free Time ◽

Isophorone Diisocyanate ◽

H Nmr ◽

Ft Ir ◽

Lower Elongation ◽

The Fourier Transform ◽

Derivatives Of ◽

Aqueous oil-modified polyurethane dispersions (PUDs) were synthesized using alcoholysis derivatives of vegetable oil, hydroxyl-terminated polyether, isophorone diisocyanate (IPDI) and dimethylolbutyric acid (DMBA). Alcoholysis was performed in order to insert alcoholysis derivatives, which were used as the polyol composition. The structures of alcoholysis derivatives, polyurethane dispersions and their dry films were confirmed by the Fourier Transform Infrared Spectroscopy (FT-IR) and 1H Nuclear Magnetic Resonance (1H-NMR), respectively. The effect of alcoholysis derivatives on the properties of PUD films was investigated. The results show that tack-free time and gloss of PUD films would change with the amount of alcoholysis derivatives. When compared to aqueous polyurethane dispersions, aqueous oil-modified PUDs have shorter tack-free time, higher gloss and tensile strength and lower elongation at broken.

Preparation and characterization of aqueous polyurethane dispersions containing ionic centers

Journal of Applied Polymer Science ◽

10.1002/app.26138 ◽

2007 ◽

Vol 104 (6) ◽

pp. 3931-3937 ◽

Cited By ~ 29

Author(s):

M. Barikani ◽

M. Valipour Ebrahimi ◽

S. M. Seyed Mohaghegh

Keyword(s):

Characterization of carbides in M50NiL

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087343 ◽

1991 ◽

Vol 49 ◽

pp. 606-607

Author(s):

L. S. Lin ◽

K. P. Gumz ◽

A. V. Karg ◽

C. C. Law

Keyword(s):

Temperature Effects ◽

Base Composition ◽

Lattice Parameter ◽

Control Surface ◽

Carbide Formation ◽

Particle Sizes ◽

Low Carbon ◽

Fee Structure ◽

Heat Treated

Carbon and temperature effects on carbide formation in the carburized zone of M50NiL are of great importance because they can be used to control surface properties of bearings. A series of homogeneous alloys (with M50NiL as base composition) containing various levels of carbon in the range of 0.15% to 1.5% (in wt.%) and heat treated at temperatures between 650°C to 1100°C were selected for characterizations. Eleven samples were chosen for carbide characterization and chemical analysis and their identifications are listed in Table 1.Five different carbides consisting of M6C, M2C, M7C3 and M23C6 were found in all eleven samples examined as shown in Table 1. M6C carbides (with least carbon) were found to be the major carbide in low carbon alloys (<0.3% C) and their amounts decreased as the carbon content increased. In sample C (0.3% C), most particles (95%) encountered were M6C carbide with a particle sizes range between 0.05 to 0.25 um. The M6C carbide are enriched in both Mo and Fe and have a fee structure with lattice parameter a=1.105 nm (Figure 1).

Facile Synthesis and Characterization of Palm CNF-ZnO Nanocomposites with Antibacterial and Reinforcing Properties

International Journal of Molecular Sciences ◽

10.3390/ijms22115781 ◽

2021 ◽

Vol 22 (11) ◽

pp. 5781

Author(s):

Janarthanan Supramaniam ◽

Darren Yi Sern Low ◽

See Kiat Wong ◽

Loh Teng Hern Tan ◽

Bey Fen Leo ◽

...

Keyword(s):

Plant Biomass ◽

Cellulose Nanofibers ◽

High Strength ◽

Salmonella Typhi ◽

Particle Sizes ◽

Mechanical Reinforcement ◽

Uniform Size ◽

Preparation Methods ◽

Potential Applications

Cellulose nanofibers (CNF) isolated from plant biomass have attracted considerable interests in polymer engineering. The limitations associated with CNF-based nanocomposites are often linked to the time-consuming preparation methods and lack of desired surface functionalities. Herein, we demonstrate the feasibility of preparing a multifunctional CNF-zinc oxide (CNF-ZnO) nanocomposite with dual antibacterial and reinforcing properties via a facile and efficient ultrasound route. We characterized and examined the antibacterial and mechanical reinforcement performances of our ultrasonically induced nanocomposite. Based on our electron microscopy analyses, the ZnO deposited onto the nanofibrous network had a flake-like morphology with particle sizes ranging between 21 to 34 nm. pH levels between 8–10 led to the formation of ultrafine ZnO particles with a uniform size distribution. The resultant CNF-ZnO composite showed improved thermal stability compared to pure CNF. The composite showed potent inhibitory activities against Gram-positive (methicillin-resistant Staphylococcus aureus (MRSA)) and Gram-negative Salmonella typhi (S. typhi) bacteria. A CNF-ZnO-reinforced natural rubber (NR/CNF-ZnO) composite film, which was produced via latex mixing and casting methods, exhibited up to 42% improvement in tensile strength compared with the neat NR. The findings of this study suggest that ultrasonically-synthesized palm CNF-ZnO nanocomposites could find potential applications in the biomedical field and in the development of high strength rubber composites.

Preparation and characterization of thermoplastic water-borne polycarbonate-based polyurethane dispersions and cast films

Journal of Applied Polymer Science ◽

10.1002/app.42672 ◽

2015 ◽

Vol 132 (42) ◽

pp. n/a-n/a ◽

Cited By ~ 16

Author(s):

Magdalena Serkis ◽

Rafał Poręba ◽

Jiří Hodan ◽

Jana Kredatusová ◽

Milena Špírková

Keyword(s):

Cast Films ◽

Water Borne

Estimating the shape and size of supramolecular assemblies by variable temperature diffusion ordered spectroscopy

Organic & Biomolecular Chemistry ◽

10.1039/c4ob01373e ◽

2014 ◽

Vol 12 (40) ◽

pp. 7932-7936 ◽

Cited By ~ 23

Author(s):

Benjamin M. Schulze ◽

Davita L. Watkins ◽

Jing Zhang ◽

Ion Ghiviriga ◽

Ronald K. Castellano

Keyword(s):

Self Assembly ◽

Variable Temperature ◽

Supramolecular Assemblies ◽

The Self ◽

Conjugated Oligomers ◽

Photovoltaic Devices ◽

Temperature Diffusion ◽

Shape And Size

Reported is characterization of the self-assembly of π-conjugated oligomers, molecules studied recently in photovoltaic devices, using variable temperature diffusion ordered spectroscopy; the approach has allowed estimation of assembly size, shape, and molecularity.

Immobilization and Characterization of Tannase and its Haze-removing

Food Science and Technology International ◽

10.1177/1082013209352919 ◽

2009 ◽

Vol 15 (6) ◽

pp. 545-552 ◽

Cited By ~ 9

Author(s):

Erzheng Su ◽

Tao Xia ◽

Liping Gao ◽

Qianying Dai ◽

Zhengzhu Zhang

Keyword(s):

Kinetic Parameter ◽

High Activity ◽

Green Tea ◽

Storage Stability ◽

Residual Activity ◽

Black Tea ◽

Optimum Temperature ◽

Oolong Tea ◽

Optimum Ph

Tannase was effectively immobilized on alginate by the method of crosslinking-entrapment-crosslinking with a high activity recovery of 76.6%. The properties of immobilized tannase were investigated. Its optimum temperature was determined to be 35 ° C, decreasing 10 °C compared with that of free enzyme, whereas the optimum pH of 5.0 did not change. The thermal and pH stabilities of immobilized tannase increased to some degree. The kinetic parameter, Km, for immobilized tannase was estimated to be 11.6 × 10-4 mol/L. Fe2+ and Mn2+ could activate the activity of immobilized tannase. The immobilized tannase was also applied to treat the tea beverage to investigate its haze-removing effect. The content of non-estern catechins in green tea, black tea and oolong tea increased by 52.17%, 12.94% and 8.83%, respectively. The content of estern catechins in green tea, oolong tea and black tea decreased by 20.0%, 16.68% and 5.04%, respectively. The anti-sediment effect of green tea infusion treated with immobilized tannase was significantly increased. The storage stability and reusability of the immobilized tannase were improved greatly, with 72.5% activity retention after stored for 42 days and 86.9% residual activity after repeatedly used for 30 times.