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The influence of the NCO/OH ratio and the 1,6-hexanediol/ dimethylol propionic acid molar ratio on the properties of waterborne polyurethane dispersions based on 1,5-pentamethylene diisocyanate

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Frontiers of Chemical Science and Engineering 2019年第1期13卷 80-89页

作者： Jiao Feng Qiuhao Lu Weimin Tan Kequan Chen Pingkai Ouyang State Key Laboratory of Materials-Oriented Chemical Engineering College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University Nanjing 211816 China National Engineering Research Center for Coatings CNOOC Changzhou Paint and Coatings Industry Research Institute Co. Ltd. Changzhou 213016 China

1,5-Pentamethylene diisocyanate, a novel aliphatic diisocyanate formed from bio-based 1,5-pentamethylenediamine, has been used as a hard segmented material to synthesize polyurethane. In this study, several waterborne polyurethane (WPU) dispersions have been successfully prepared by a prepolymer process from 1,5-pentamethylene diisocyanate poly(polyether) with different NCO/OH ratios and 1,6-hexanediol (HDO)/dimethylol propionic acid (DMPA) molar ratios. The Fourier transfonn infrared (FTIR) spectra, thermogravimetric analysis, differential scanning calorimetry, X-ray diffiraction, and a mechanical tensile test were used to investigate the structures, thermal stability, phase separation, crystallinity, mechanical properties, and adhesive performance of the WPU dispersions. The FTIR results indicate that the degree of hydrogen bonding and the numbers of urea groups increase as the NCO/OH ratio and HDO/DMPA molar ratio increase. Furthermore, the phase separation increases and the thermal stability decreases as the NCO/OH ratio increases or the HDO/DMPA molar ratio decreases. Finally, WPU3.0-2.4 (NCO/OH = 3, HDO/DMPA = 2.4) exhibits a maximum tensile strength and shear strength, pointing to its possible use as an adhesive. These results could provide a very valuable reference for industrial applications of WPU.

关键词： 1,5-pentamethylene diisocyanate polyurethane water based

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Synthesis and Properties of Organic-Inorganic Hybrid Porous Polymers Obtained with Click Addition Reactions of Thiol-Functionalized Random Type Silsesquioxane by and Diacrylate or diisocyanate Compounds

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Open Journal of Polymer Chemistry 2020年第1期10卷 1-20页

作者： Tomoharu Miyanaga Naofumi Naga Graduate School of Engineering and Science Shibaura Institute of Technology Tokyo Japan Department of Applied Chemistry College of Engineering Shibaura Institute of Technology Tokyo Japan

Organic-inorganic hybrid network polymers have been synthesized by addition reaction of a thiol-functionalized random type silsesquioxane (SQ109) and alkyl diacrylate or diisocyanate compounds. Thiol-ene reaction of SQ109 and 1,4-butanediol diacrylate (BDA) successfully yield porous polymer in toluene initiated by azobis(isobutyronitrile) (AIBN) at 60°C. Morphology of the porous polymers was composed by connected globules, and the diameter of the globules decreased with increasing in the monomer concentration of the reaction system. By contrast, the reaction with 1,6-hexanediol diacrylate or 1,5-hexadiene yielded homogeneous clear gels. Thermal analyses of SQ109-BDA porous polymers indicated that thermal degradation of ester groups of BDA in the polymer network occurred at around 300°C. The porous polymer was also obtained by the reaction using a photo-initiator (Irugacure184) at room temperature, and showed higher Young’s modulus than the corresponding porous polymer obtained with the reaction with AIBN due to the small size of the globules. Young’s modulus

关键词： Silsesquioxane Thiol Diacrylate diisocyanate Gel Porous Polymer Morphology

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NMR Analysis to Identify Biuret Groups in Common Polyureas

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Chinese Journal of Polymer Science 2018年第10期36卷 1150-1156页

作者： Wei-Guang Qiu Fei-Long Zhang Xu-Bao Jiang Xiang-Zheng Kong College of Chemistry and Chemical Engineering University of Jinan

Polyureas （PU） are well known as a class of high impact engineering materials, and widely used also in emerging advanced applications. As a general observation, most of them are only soluble in a very limited number of highly protonic solvents, which makes their chemical structure analysis a great challenge. Besides the presence of abundant hydrogen bonding, the poor solubility of PU in common organic solvents is often ascribed to the formation of biuret crosslinking in their molecular chains. To clarify the presence of biuret groups in PU has been of great interest. To this end, two samples, based on hexamethylene diisocyanate （HDI） and toluene diisocyanate （TDI） respectively, were synthesized by precipitation polymerization of each of these diisocyanates in water-acetone at 30℃. Their chemical structures were analyzed by high resolution magic angle spinning （HR-MAS） NMR, and through comparison of their NMR spectra with those of specially prepared biuret-containing polyurea oligomers, it was concluded that biuret group was absent in all the PU prepared at 30 ℃. In addition, this NMR analysis was also applied to a PU obtained by copolymerization of TDI with ethylene diamine （EDA） and water at 65 ℃ in EDA aqueous solution. It was confirmed that biuret unit was also absent in this PU and that EDA was more active than water towards TDI. The presence of EDA was crucial to the formation of uniform PU microspheres. This study provides therefore a reliable method for the analysis of PU chemical structure.

关键词： diisocyanate Polyurea Chemical structure Biuret NMR spectroscopy

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Valorization of Kraft Lignin as Thickener in Castor Oil for Lubricant Applications

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Journal of Renewable Materials 2018年第4期6卷 347-361页

作者： A.M.Borrero-Lopez F.J.Santiago-Medina C.Valencia M.E.Eugenio R.Martin-Sampedro J.M.Franco Department of Chemical Engineering University of HuelvaEl Carmen CampusAgrifood Campus of International Excellence(ceiA3)21071 HuelvaSpain Pro2TecS-Chemical Process and Product Technology Research Center University of Huelva21071 HuelvaSpain INIA-CIFOR Ctra de la Coruñakm 7.5.28040MadridSpain

It is known that large amounts of residual lignin are generated in the pulp and paper industry.A new alternative for Kraft lignin valorization,which consists of first a chemical modification using a diisocyanate and then the efficient dispersion in castor oil to achieve stable gel-like systems,is proposed in this *** properties and microstructure of these materials were determined by means of small amplitude oscillatory shear tests and viscous flow measurements and atomic force microscopy observations,***,both standardized penetration tests and tribological assays,usually performed in the lubricant industry,were carried out to evaluate the performance characteristics as lubricating *** viscoelasticity functions are affected by the lignin/diisocyanate ratio and thickener *** thermorheological response evidenced a softening temperature of around 105°*** microstructure of these gel-like dispersions is composed of interconnected thin fibers,homogeneously distributed in castor ***,the NCO-functionalized lignin gel-like dispersions studied show lower friction coefficients than traditional lubricating greases.

关键词： Kraft lignin diisocyanate gel-like dispersion rheology thermal properties

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Influences of Diamines on the Morphologies and the Chemical, Thermal, and Mechanical Properties of Polyurethane-Imide Elastomers

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Open Journal of Organic Polymer Materials 2017年第4期7卷 47-60页

作者： Tomohiro Ueda Tomohiro Nishio Shinichi Inoue Department of Applied Chemistry Aichi Institute of Technology Toyota Japan Technical Center Department of Product Development Nitta Corporation Ltd. Yamatokohriyama Japan

Polyurethane-imide elastomers (PUIEs) are formed from isocyanate, polyol, acid anhydride, and diamine by liquid polymerization. Unfortunately, many of the diamines have rarely been applied to the formation of PUIEs. Hence, investigating the effect of diamines on PUIEs remains a challenge in polymer chemistry. Herein, PUIEs prepared from 4,4'-diphenylmethane diisocyanate (MDI), polytetramethylene glycol (Mw: 1000), pyromellitic dianhydride, and aromatic diamines (such as p-phenylene diamine, 4,4'-oxydianiline, and 1,3-bis(4-aminophenoxy)benzene), and aliphatic diamines (such as 1,2-ethylene diamine, 1,6-hexamethylene diamine, and 1,12-dodecamethylene diamine) were synthesized by liquid polymerization. The morphologies and the chemical, thermal, and mechanical properties of the various PUIEs were investigated. The obtained elastomeric sheets were characterized in terms of the following tests and methods: solubility and swelling tests, X-ray diffraction and differential scanning calorimetry, dynamic mechanical analysis and thermogravimetric analysis, tensile tests, nuclear magnetic resonance spectroscopy, infrared spectroscopy, atomic force microscopy, contact angle microscopy, and scanning electron

关键词： Polyurethane-Imide diisocyanate Polyol Diamine Pyromellitic Dianhydride Solution Polymerization

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POLYETHER POLYURETHANE FROM MODIFIED WHEAT STRAW OXYGEN-ALKALINE LIGNIN

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天津科技大学学报 2004年第S2期 82-86页

作者： Quanxiao Liu, Huaiyu Zhan, Beihai He State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, 510640, P. R. China Shuhui YangTianjin University of Science and Technology, Tianjin, 300222, P. R. China Jianhua Liu Jianlu Liu, Zhenxing Pang Shandong Haihua Group Co. Ltd., Weifang, Shandong, 262737, P. R. China

Polyether polyurethane was synthesized from modified wheat straw oxygen-alkaline lignin, polyethylene glycol and two different diisocyanates (diphenylemethane-4, 4’-diisocyanate, tolulene diisocyanate) by solution casting method, its properties were investigated. The results show that modified wheat straw oxygen-alkaline lignin can substitute part of polyethylene glycol to react with diisocyanate to synthesize polyurethane. The molar ratio of NCO to OH and modified wheat straw oxygen-alkaline lignin content affect the properties of lignin-based polyether polyurethane respectively. The addition of plasticizer in the polyurethane synthesis process improves the properties of synthesized polyurethane, especially the elasticity of polyurethane. The synthesized polyurethane from modified wheat straw oxygen-alkali lignin can be used as both engineering plastic and hard foam plastic in future.

关键词： modified wheat straw oxygen-alkaline lignin diisocyanate polyethylene glycol polyurethane.

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