A Novel Approach on Preparation and Characterization of Thermosetting Fluorinated Polyurethane Coatings

2016 ◽  
Vol 852 ◽  
pp. 1025-1028 ◽  
Author(s):  
Xia Wang ◽  
Jiao Jiao Hu ◽  
Ying Li
Keyword(s):  
Corrosion Resistance ◽  
Water Resistance ◽  
Soft Segment ◽  
Crosslinking Agent ◽  
Polyurethane Coating ◽  
Fluorinated Polyurethane ◽  
Novel Approach ◽  
Polyether Polyol ◽  
Better Than

Thermosetting fluorinated polyurethane coating was prepared by using fluorinated polyether polyol (FPO) as the soft segment, 4,4`-diphenylmethane diisocyanate (MDI) as the hard segment, TEA as crosslinking agent. The structure ofthermosetting fluorinated polyurethane coating was confirmed by the use of Fourier transform infrared spectroscopy (FTIR).The FPU film’s surface property was investigated by contact angle (CA),water resistance and anti-corrosion resistance measurements. The results indicated that the surface of fluorinated polyurethanes was significantly enriched with fluorine groups. The water resistance of thermosetting FPU coating was evidently better than thermoplastic FPU coating. It was also found that the surface enrichment of fluorine atoms made the fluorinated polyurethane coating had outstanding anti-corrosion resistance.

Synthesis and characterization of non-ionic and anionic two-component aromatic waterborne polyurethane

2018 ◽  
Vol 47 (4) ◽  
pp. 290-299 ◽  
Author(s):  
Sainan Zhang ◽  
Xiankai Jiang
Keyword(s):  
Thermal Stability ◽  
Water Resistance ◽  
Soft Segment ◽  
Aqueous Dispersion ◽  
Waterborne Polyurethane ◽  
Content Type ◽  
Hydrophilic Modification ◽  
Two Component ◽  
Better Than

Purpose The purpose of this paper is to synthesize and characterize a series of two-component aromatic waterborne polyurethane (2K-WPU) which is composed of non-ionic and anionic polyisocyanate aqueous dispersion and polyurethane polyol aqueous dispersion. Design/methodology/approach The polyisocyanate aqueous dispersion was synthesized through non-ionic and anionic hydrophilic modification procedures. The values of the hydrogen bonding index (HBI) and molecule structures of WPU were obtained by Fourier transform infrared (FTIR). The thermal, mechanical and water resistance properties of 2K-WPU films were investigated. Findings The appearance of non-ionic polyisocyanate aqueous dispersion and anionic polyisocyanate aqueous dispersion was colorless translucent pan blue and yellow opaque emulsions, respectively. FTIR not only showed that 2K-WPU was obtained from the polymerization of polyisocyanate component and polyhydroxy component by polymerization but also showed that the content of hydrogen bondings of anionic 2K-WPU (WPU 2) was higher than non-ionic 2K-WPU (WPU 1). The glass-transition temperature (Tg), storage modulus and water resistance of WPU 2 were higher than WPU1, whereas the thermal stability of WPU1 was better than WPU 2. Practical implications The investigation established a method to prepare a series of 2K-WPU which was composed of non-ionic or anionic polyisocyanate aqueous dispersion and polyurethane polyol aqueous dispersion. The prepared 2K-WPU film could be applied as substrate resin material in the field of waterborne coating. Originality/value The paper established a method to synthesize a series of 2K-WPU. The effect of HBI value and the molecule structure of soft segment on the thermal stability, mechanical and water resistance properties of 2K-WPU films were studied.

scholarly journals Synthesis and Characterization of Polyether Polyol Based on Epoxy Cyclohexane and Epichlorohydrin

2020 ◽  
Vol 26 (3) ◽  
pp. 343-347
Author(s):  
Jinjie ZHANG ◽  
Yingping QI ◽  
Yinghua QIAO ◽  
Yongfeng SHEN ◽  
Hua LI
Keyword(s):  
Aluminum Chloride ◽  
Boron Trifluoride ◽  
Raw Materials ◽  
Synthesis And Characterization ◽  
Coating Film ◽  
Polyurethane Coating ◽  
Excellent Performance ◽  
Environmentally Safe ◽  
Polyether Polyol

Epoxycyclohexane-epichlorohydrin polyether polyol was synthesized by using epoxy cyclohexane and epichlorohydrin as raw materials, glycerol as an initiator, dichloromethane as solvent and aluminum chloride as catalysis. The structure of the copolyether was characterized by infrared (IR) spectroscopy and nuclear magnetic resonance (NMR), and its viscosity was determined. The results showed that the structure and viscosity properties of the products prepared by using aluminum chloride as the catalyst and the boron trifluoride diethyl ether catalyst were basically the same, but the aluminum chloride was more environmentally safe and lower in cost. At the same time, the polyurethane coating film prepared by using the copolyether synthesized by using aluminum chloride as a catalyst had excellent performance.

Preparation and Characterization of Polyurethane Foams from Modified Rosin-Based Polyether Polyol

2014 ◽  
Vol 887-888 ◽  
pp. 727-730
Author(s):  
Meng Zhang ◽  
Li Qiang Zhang ◽  
Yong Hong Zhou
Keyword(s):  
Thermal Stability ◽  
Thermal Properties ◽  
Compression Strength ◽  
Dimensional Stability ◽  
Polyurethane Foams ◽  
Mechanical And Thermal Properties ◽  
Foaming Behavior ◽  
Polyether Polyol ◽  
Better Than

Rosin based polyether polyols were synthesized from rosin formaldehyde adduct, propylene epoxide and ethylene epoxide in the presence of catalyst. Rigid polyurethane foams (PUFs) were prepared with these rosin-based polyols and compared with foam made with an industrial polyether polyol (TC-4110) and rosin-based polyester polyols. The mechanical and thermal properties of foams were analyzed by some methods. The experimental results show that the foaming behavior for the foams prepared from such rosin based polyether polyols is similar to that of industrial products, but the reaction activities were higher, the viscosities are much lower. Furthermore, their 10% compression strength and thermal stability were higher and the dimensional stability is similar or somewhat better than that of TC-4110 system. All these unique properties of rigid PUFs made with rosin based polyether polyols were more suitable for as industrial production.

scholarly journals Characterization of Wear and Corrosion Resistance of Stellite 6 Laser Surfaced Alloyed (LSA) with Rhenium

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 292
Author(s):  
Irina Smolina ◽  
Karol Kobiela
Keyword(s):  
Corrosion Resistance ◽  
Process Parameters ◽  
Corrosion Potential ◽  
Laser Surface ◽  
Stellite 6 ◽  
Wear And Corrosion ◽  
Study Results ◽  
Wear And Corrosion Resistance ◽  
Better Than

This paper presents the method of preparation and study results of the Stellite 6 laser surface alloyed (LSA) with rhenium using na LDF diode laser (4000 W). During this process, a rhenium powder was introduced onto the surface of the Co-based alloy. The possibility of improving wear and corrosion resistance properties is interesting and worth investigating. The selected process parameters: the laser power of 900 W, powder feed rate in the range 1.92–3.83 g/min, and necessarily preheating of the substrate up to 200 °C—allowing to obtain the LSA layers on the Stellite 6 substrate. Depending on the process parameters, it is possible to modify the substrate’s surface layer in terms of rhenium concentration and geometrical characteristics of the laser tracks. It was found that undissolved particles of rhenium in laser-alloyed layers have a non-significant effect on their hardness and abrasion resistance. The laser surface-alloyed corrosion potential is better than the corrosion potential of the Stellite 6 substrate, including reducing resistance to pitting corrosion with a high ability to repassivation.

scholarly journals Application of acidic protease in the pickling to simplify the pelt bating process

2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Xu Zhang ◽  
Mengchu Gao ◽  
Sadaqat Ali Chattha ◽  
Yiwen Zhu ◽  
Biyu Peng ◽  
...  
Keyword(s):  
Research Work ◽  
Collagenolytic Activity ◽  
The Novel ◽  
Leather Industry ◽  
Quantitative Characterization ◽  
Environment Friendly ◽  
Novel Approach ◽  
Pickling Process ◽  
Better Than

Abstract Traditionally, universally used pelt bating technologies rely on the application of trypsin, neutral and alkaline microbial proteases but suffer from complicated operation, limited bating efficiency and unsatisfactory leather performance. Therefore, devising a new pelt bating approach to achieve high bating efficiency and excellent leather performance has always been wished for by the leather industry. To pursue this goal, years of persistent research work enabled us to develop a novel approach for pelt bating by means of acidic proteases in pickling process. Initially, basic enzymatic characteristics and bating effectiveness of several typical acidic proteases in pelt pickling medium were investigated; then, the bating effectiveness through the quantitative characterization of protease activity of the optimal acidic protease was compared with that of the conventional bating enzyme. The results indicated that all of the selected acidic proteases had good salt-tolerance and exhibited optimum activity at pH 3.0–4.0. The novel pickling-bating method based on microbial origin acidic protease L80A led to an outstanding performance on pelt bating at the dosage of 150 U/mL of collagenolytic activity. The bating effectiveness of acidic protease L80A was comparable to and even better than that of trypsin BEM due to its moderate proteolytic ability. Moreover, the deep and even penetration of acidic protease in the pelt permitted it to produce soft, organoleptically stable and overall better quality crust leather than that of the conventional trypsin bating method. Additionally, pelt bating was performed along with the pickling process without extra inactivation and washing operation, making the bating operation more efficient, economical, and environment friendly. Results had made us to conclude that this cutting-edge acidic proteases based pickling-bating method could be the first step/ way forward to replace the decades-old traditional pelt bating technology.

scholarly journals Synthesis and Characterization of Epoxy Resins-Modified Waterborne Polyurethane Emulsion

2021 ◽  
pp. 1-9
Author(s):  
Chenhan Zhuang ◽  
Weilan Xue ◽  
Zuoxiang Zeng
Keyword(s):  
Epoxy Resin ◽  
Water Resistance ◽  
Raw Materials ◽  
Waterborne Polyurethane ◽  
Polyurethane Film ◽  
Modification Method ◽  
Suitable Amount ◽  
Overall Performance ◽  
Better Than

Aqueous polyurethane emulsion was prepared with diphenylmethane diisocyanate (MDI), polybutylene adipate diol (PBA-1000) as main raw materials and 2, 2-dihydroxymethyl propionic acid (DMPA) as hydrophilic chain extender. On this basis, epoxy resin E-44 was introduced to modify the polyurethane prepolymer, and epoxy resin modified waterborne polyurethane emulsion was obtained. In order to obtain better performance waterborne polyurethane, the effect of DMPA content、the amount of epoxy resin added and modification method on the properties of polyurethane was discussed. The results show that when the DMPA content is 4wt%, the overall performance of the emulsion and the film is the best. And the addition of epoxy resin significantly improves the water resistance, solvent resistance and tensile strength of the waterborne polyurethane film, and its hardness and thermal stability are also improved to a certain extent. When the amount of epoxy resin added is 8wt%, the storage stability decreases significantly, the suitable amount of epoxy resin added is 6wt%. The overall performance of the film obtained by chemical modification is better than that of physical modification.

scholarly journals Investigations of Ballistic Characteristics of N340 Propellant

2017 ◽  
Vol 8 (4) ◽  
pp. 9-22
Author(s):  
Radosław TRĘBIŃSKI ◽  
Bartosz FIKUS ◽  
Zbigniew SURMA
Keyword(s):  
Analytical Approximation ◽  
Heat Losses ◽  
The Novel ◽  
Closed Vessel ◽  
Novel Approach ◽  
Small Influence ◽  
Ballistic Properties ◽  
Better Than

Results of investigations of ballistic characteristics of the single-based N340 propellant are presented. A novel approach, proposed in an earlier authors’ work, was applied. Basing on pressure records, obtained in closed vessel tests the burning law and the dynamic vivacity function were determined. High value of the exponent in the burning law was obtained (1.25). This effect can be attributed to the process of infiltration of hot gases into propellant pores, enhanced by the increase in the pressure. The dynamic vivacity function was proved to be dependent on the value of the loading density. A simple analytical approximation of the averaged vivacity function was proposed. It describes the ballistic properties of the propellant much better than the geometric law of combustion. An effect of heat losses on the vivacity function was estimated, showing relatively small influence of the losses on the vivacity function. The obtained results confirmed applicability of the novel approach to the characterization of ballistic properties of fined-grained propellants.

Synthesis and Characterization of Polyorganosiloxane Modified Waterborne Polyurethane

2009 ◽  
Vol 79-82 ◽  
pp. 1055-1058
Author(s):  
Sui Lian Luo ◽  
Chao Dong Liu ◽  
Guo Fei Gong ◽  
Hei Ping Lai ◽  
Wen Zhong Kong
Keyword(s):  
Particle Size ◽  
Tensile Strength ◽  
Water Resistance ◽  
Soft Segment ◽  
Waterborne Polyurethane ◽  
Synthesis And Characterization ◽  
Wood Coatings ◽  
Weather Resistance ◽  
Improve Water Resistance

In this work, PDMS modified PU was synthesized using two-stage method to improve water resistance and weather resistance in the waterborne polyurethane was investigated. It was found that the absorbed water content decreased with increasing PDMS content in polyurethane. It was also found that PDMS modified polyurethane had better solvent resistance than unmodified polyurethane. The structure incorporated the PDMS into the soft segment of polyurethane chains was confirmed by FTIR. The phase separation increased by increasing PDMS content and was confirmed by DSC. The particle size of the dispersions increased and tensile strength and hardness decreased with the increase of PDMS content. Furthermore, with the improved water resistance and elongation, it was hoped that the modified polyurethane could be used as wood coatings superior to the solvent-borne systems.

Characterization of Rh/Si multilayer structure by HREM and HAADF

1992 ◽  
Vol 50 (1) ◽  
pp. 122-123
Author(s):  
Y. Cheng ◽  
J. Liu ◽  
M.B. Stearns ◽  
D.G. Steams
Keyword(s):  
Normal Incidence ◽  
High Resolution Electron Microscopy ◽  
X Rays ◽  
Beam Direction ◽  
Cross Sectional ◽  
Optical Elements ◽  
Resolution Electron ◽  
Point To Point ◽  
Better Than

The Rh/Si multilayer (ML) thin films are promising optical elements for soft x-rays since they have a calculated normal incidence reflectivity of ∼60% at a x-ray wavelength of ∼13 nm. However, a reflectivity of only 28% has been attained to date for ML fabricated by dc magnetron sputtering. In order to determine the cause of this degraded reflectivity the microstructure of this ML was examined on cross-sectional specimens with two high-resolution electron microscopy (HREM and HAADF) techniques.Cross-sectional specimens were made from an as-prepared ML sample and from the same ML annealed at 298 °C for 1 and 100 hours. The specimens were imaged using a JEM-4000EX TEM operating at 400 kV with a point-to-point resolution of better than 0.17 nm. The specimens were viewed along Si [110] projection of the substrate, with the (001) Si surface plane parallel to the beam direction.

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