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Synthetic Process of Bio-Based Phenol Formaldehyde Adhesive Derived from Demethylated Wheat Straw Alkali Lignin and Its curing behavior

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Journal of Renewable Materials 2021年第5期9卷 943-957页

作者： Yan Song Zhixin Wang Xin Zhang Rong Zhang Jinchun Li Faculty of Materials Science&Engineering Changzhou UniversityChangzhou213164China Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials School of Materials Science and EngineeringChangzhou UniversityChangzhou213164China Organization Department of the Party Committee Changshu Institute of TechnologyChangshu215500China School of Petrochemical Engineering Changzhou UniversityChangzhou213164China

Lignin is a natural biopolymer with a complex three-dimensional network, commercially obtained from wasteliquid of paper pulp and bioethanol production, and could be a candidate for preparation of environment-friendlybio-based polyphenol material. In the present work, the demethylated wheat straw alkali lignin (D-Lig), preparedby demethylation of wheat straw alkali lignin (Lig) using an in-situ generated Lewis acid, was used to synthesizebio-based phenol formaldehyde resin adhesive (D-LPF) applied in plywood. Effects of synthetic process’s factors,including lignin substitution for phenol, NaOH concentration and molar ratio of formaldehyde to phenol, on thebonding strength and free formaldehyde content of D-LPF were investigated in detail, and the optimum syntheticprocess of D-LPF was obtained as following: Lignin substitution for phenol 60%, NaOH concentration 5.0% andmolar ratio of formaldehyde to phenol 2.0, and under the optimum reaction condition, the D-LPF presented lower free formaldehyde content (0.18%) and higher bonding strength (2.19 MPa), which was better than those ofcontaining-lignin phenol formaldehyde resin adhesive (LPF). Additionally, the curing behavior of the adhesivewas studied by differential scanning calorimetry (DSC) combined with gel time. It can be obtained that D-LPFresin adhesive had the shortest gel time, and fastest curing rate, compared with those of PF and L-PF resin adhesives. The curing kinetics data was fitted well by Kissinger model using non-isothermal DSC method, and theaverage activation energy value was 85.3 kJ/mol, slightly higher than that of commercial PF resin, while lowerthan that of LPF (90.2 kJ/mol). Finally, based on the analytical results of high temperature fourier transform infrared spectroscopy (FTIR), a possible curing mechanism of D-LPF was proposed.

关键词： Lignin demethylation phenol-formaldehyde resin biobased adhesive synthetic process curing behavior

curing behaviors and Thermal Properties of Dimer Fatty Acid （DFA） Modified Multifunctional Epoxy Resin

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Journal of Donghua University(English Edition) 2013年第6期30卷 525-529页

作者： Yu, Ming-Ming Sun, Jin-Liang Ren, Mu-Su Li, Ai-Jun Bai, Rui-Cheng Hu, He-Feng Research Center for Composite Materials Shanghai University Shanghai 200072 China Department of Polymer Materials Shanghai University Shanghai 201800 China

In order to improve the toughness of the cured aromatic tetrafunctional epoxy resins, a dlmer rarboxylic acid named dlmer fatty acid （DFA） was used to modify an aromatic tetrafunctional epoxy, N, N, N＇, N＇-tetraglycidyl-2,2-bis [ 4-（ 4-aminophcuoxy ） phenyl ] propane （TGBAPP）. The curing behaviors of DFA- TGBAPP/MNA （ methyl nadic anhydride） systems were studied by differential scanning calorimetry （DSC） method. And the thermal properties of the cured epoxy resin were investigated with the thermo-gravimetric analysis （TGA） and dynamic mechanical analysis （DMA）. Besides, the toughness was characterized with the impact strength tested by charpy impact testing. The results indicated that the modification would improve the curing reactions, and the curing temperatures were decreased with the increasing content of DFA. The thermal properties were not influenced obviously, and the toughness could be improved when the epoxy resin was modified with DFA.

关键词： curing behavior thermal property N, N, N', N'- telraglycidyl-2, 2-bis [ 4-( 4-aminophenoxy ) phenyl ] propane (TGBAPP) dimer fatty acid ( DFA) toughen

Synthesis, Characterization of Phosphorus Containing Diamide-diimide-tetraamines Based on L-Tryptophan Amino Acid and Their Effect on Flame Retardancy of Epoxy Resins

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Chinese Journal of Polymer Science 2014年第2期32卷 197-208页

作者： Seema Agrawal Anudeep Kumar Narula GGS Indraprastha University

The curing behavior of diglycidyl ether of bisphenol-A （DGEBA） with different phosphorus containing diamidediimide-tetraamines （DADITAs） was studied by DSC. Eight DADITAs of varying structures were synthesized by reacting 1 mole of pyromellitic anhydride （PMDA）/3,3＇-benzophenone tetracarboxylic dianhydride （BTDA）/1,4,5,8-naphthalene tetraearboxylic dianhydride （NTDA）/4,4＇-oxydiphthalic anhydride （ODPA） with 2 mole of L-tryptophan （T） in a mixture of acetic acid and pyridine （3：2 V/V） followed by activaton with thionyl chloride and then condensation with excess of phosphorus containing triamines tris（3-aminophenyl） phosphine （TAP） and tris（3-aminophenyl） phosphine oxide （TAPO）. DADITAs obtained by reacting PMDA/BTDA/NTDA/ODPA with L-tryptophan followed by condensation with TAP/TAPO were designated as PTAP, PTAPO, BTAP, BTAPO, NTAP, NTAPO, OTAP and OTAPO respectively. The structural characterization of synthesized DADITAs was done by FTIR, ~H-NMR, I3C-NMR, 31p-NMR spectroscopic techniques and elemental analysis. Thermal stability of the isothermally cured epoxy was investigated using dynamic thermogravimetry analysis. The glass transition temperature （Tg） was highest in DGEBA cured using PTAP. All epoxy thermosets exhibited excellent flame retardancy, moderate changes in Tg and thermal stability. Due to presence of phosphorus in curing agents, all epoxy resin systems met the UL-94 V-0 classification and the limiting oxygen index （LOI） reached up to 38.5, probably because of the nitrogen-phosphorus synergistic effect.

关键词： Diamide-diimide-tetraamines DGEBA curing behavior Thermal stability Flame retardancy.

Phthalonitrile-PPO Blends: Cure behavior and Properties

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Chinese Journal of Polymer Science 2018年第4期36卷 497-504页

作者： Jing-Zhi Ma Kang Cheng Jiang-Bo Lv Chang Chen Jiang-Huai Hu Ke Zeng Gang Yang State Key Laboratory of Polymer Materials Engineering College of Polymer Science and Engineering Sichuan University

Hydroxy-containing low molecular weight poly（2,6-dimethyl-1,4-phenylene oxide）（r PPO） and self-promoted hydroxycontaining phthalonitrile（HPPH） were prepared by redistribution reaction and the simple nucleophilic displacement of a nitro-substituent from 4-nitrophthalonitrile in a dipolar aprotic solvent respectively. The hydroxy-containing phthalonitriles modified by r PPO were prepared by mechanical blending without compatibilizer, followed by heating. The curing behavior was studied using dynamic rheological analysis, and the results showed that the r PPO-modified phthalonitrile exhibited a large processing window（over-67 °C） and complex viscosity（0.18-0.8 Pa·s） at moderate temperatures. After curing at 300 °C, the resulting polymers showed good thermal stability and high modulus as observed by thermogravimetric analysis（TGA） and dynamic mechanical analysis（DMA）. The dielectric properties and the morphology of r PPO-modified phthalonitrile networks were studied by dielectric analysis and field-emission scanning electron microscopy（SEM）.

关键词： Low molecular weight PPO Phthalonitrile curing behavior Dielectric properties

Thermosetting resin modified asphalt:A comprehensive review

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第6期10卷 1001-1036页

作者： Zengping Zhang Hao Liu Xiaoyi Ban Xiaosong Liu Yinxiao Guo Jia Sun Yanqi Liu Suyu Zhang Jiahao Lei Key Laboratory for Special Area Highway Engineering of Ministry of Education Chang'an UniversityXi'an 710064China School of Transportation Southeast UniversityNanjing 210096China Chang'an Dublin Internaitonal College of Transportation Chang'an UniversityXi'an 710064China College of Future Transportation Chang'an UniversityXi'an 710064China

Thermosetting resins have advantages such as high strength,corrosion resistance,and aging resistance,and have excellent prospects for practical application as asphalt *** order to promote the research of thermosetting resin modified asphalt,to provide direction for its further research,this paper reviews the research progress of thermosetting resin modified asphalt in recent *** material composition,modification mechanism,and curing behavior of epoxy asphalt,thermosetting polyurethane modified asphalt,unsaturated polyester modified asphalt,and other thermosetting resin modified asphalts are *** types of thermosetting resin modified asphalt have different performances,the performance advantages of different thermosetting resin modified asphalts are *** the same time,the existing problems in thermosetting resin modified asphalt and further research directions are *** researchers to produce thermosetting resin modified asphalts using waste or bio-based materials,and to study the recycling technologies and life cycle assessment of thermosetting resin modified *** paper provides a reference for the study of thermosetting resin modified asphalt.

关键词： Pavement Modified asphalt Thermosetting resin curing behavior Modification mechanism