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Synthesis, performance and structure characterization of glyoxal-monomethylolurea-melamine (G-MMU-M) co-condensed resin. Chin J Chem Eng 2022. [DOI: 10.1016/j.cjche.2022.09.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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2
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Okhrimenko D, Thomsen A, Ceccato M, Johansson D, Lybye D, Bechgaard K, Tougaard S, Stipp S. Impact of curing time on ageing and degradation of phenol-urea-formaldehyde binder. Polym Degrad Stab 2018. [DOI: 10.1016/j.polymdegradstab.2018.04.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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3
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Wang H, Cao M, Li T, Yang L, Duan Z, Zhou X, Du G. Characterization of the Low Molar Ratio Urea⁻Formaldehyde Resin with 13C NMR and ESI⁻MS: Negative Effects of the Post-Added Urea on the Urea⁻Formaldehyde Polymers. Polymers (Basel) 2018; 10:polym10060602. [PMID: 30966636 PMCID: PMC6403571 DOI: 10.3390/polym10060602] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 05/18/2018] [Accepted: 05/24/2018] [Indexed: 11/23/2022] Open
Abstract
The structural changes during three-step synthesis of low-molar ratio urea–formaldehyde (UF) resin were tracked by quantitative 13C nuclear magnetic resonance (13C NMR) analysis and electrospray ionization-mass spectrometry (ESI–MS). Condensations that produced polymers were found to be linked by ether bonds in addition to hydroxymethylation reactions at the first alkaline stage with a formaldehyde to urea ratio of 2:1. Considerable formation of branched methylene linkages, with the highest content among all the condensed structures, was the key feature of the acidic stage. Notable changes were observed for the chemical structures and molecular masses of the resin components after the formaldehyde to urea molar ratio was lowered to 1.2 by adding post-urea at the final alkaline stage. Specifically, most of the branched hydroxymethyl groups on the polymers were cleaved, resulting in a significant decrease in the branching degree of the polymers. The performance degradation of the UF resin was attributed to this debranching effect and the production of components with low molecular masses. Based on the observations, the curing pattern of low molar ratio UF resin was postulated and branched polymeric formaldehyde catcher bearing urea-reactivity was proposed.
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Affiliation(s)
- Hui Wang
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
| | - Ming Cao
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
| | - Taohong Li
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
- Key Lab for Forest Resources Conservation and Utilisation in the Southwest Mountains of China, Southwest Forestry University, Ministry of Education, Kunming 650224, China.
| | - Long Yang
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
- Key Lab for Forest Resources Conservation and Utilisation in the Southwest Mountains of China, Southwest Forestry University, Ministry of Education, Kunming 650224, China.
| | - Zhigang Duan
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
| | - Xiaojian Zhou
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
| | - Guanben Du
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
- Key Lab for Forest Resources Conservation and Utilisation in the Southwest Mountains of China, Southwest Forestry University, Ministry of Education, Kunming 650224, China.
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4
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Chemical and Molecular Variations in Commercial Epoxide Photoresists for X-ray Lithography. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app8040528] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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5
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Li T, Cao M, Liang J, Xie X, Du G. New Mechanism Proposed for the Base-Catalyzed Urea⁻Formaldehyde Condensation Reactions: A Theoretical Study. Polymers (Basel) 2017; 9:E203. [PMID: 30970883 PMCID: PMC6432254 DOI: 10.3390/polym9060203] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 05/27/2017] [Accepted: 05/27/2017] [Indexed: 11/16/2022] Open
Abstract
Base-catalyzed urea⁻formaldehyde condensation reactions were investigated by using a quantum chemistry method. It was found that monomethylolurea or N,N'-dimethylolurea can produce the methyleneurea intermediate (⁻HN⁻CO⁻N=CH₂) with the catalysis of base. The E1cb (unimolecular elimination of conjugate base) mechanism was identified for the formation of such an intermediate. The potential energy barrier was theoretically predicted to be 59.6 kJ/mol for the E1cb step, which is about half of that of previously proposed SN2 (bimolecular nucleophilic substitution) mechanism. In the subsequentcondensation reactions, Michael addition reactions that lead to different condensed structures can occur between the methyleneurea intermediate and the anions produced from methylolureas under alkaline conditions. Based on the theoretical calculations on the kinetics and thermodynamics of the selected reactions, the competitive formations of methylene linkages, ether linkages and uron were discussed in combination with our previous experimental observations.
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Affiliation(s)
- Taohong Li
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
- Key Lab for Forest Resources Conservation and Utilisation in the Southwest Mountains of China, Southwest Forestry University, Ministry of Education, Kunming 650224, China.
| | - Ming Cao
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
- Key Lab for Forest Resources Conservation and Utilisation in the Southwest Mountains of China, Southwest Forestry University, Ministry of Education, Kunming 650224, China.
| | - Jiankun Liang
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
- Key Lab for Forest Resources Conservation and Utilisation in the Southwest Mountains of China, Southwest Forestry University, Ministry of Education, Kunming 650224, China.
| | - Xiaoguang Xie
- School of Chemical Science and Technology, Yunnan University, Kunming 650091, China.
| | - Guanben Du
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
- Key Lab for Forest Resources Conservation and Utilisation in the Southwest Mountains of China, Southwest Forestry University, Ministry of Education, Kunming 650224, China.
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Cao M, Li T, Liang J, Wu Z, Zhou X, Du G. A 13C-NMR Study on the 1,3-Dimethylolurea-Phenol Co-Condensation Reaction: A Model for Amino-Phenolic Co-Condensed Resin Synthesis. Polymers (Basel) 2016; 8:E391. [PMID: 30974669 PMCID: PMC6432414 DOI: 10.3390/polym8110391] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 10/31/2016] [Accepted: 11/01/2016] [Indexed: 11/17/2022] Open
Abstract
The reactions of di-hydroxymethylurea with phenol under alkaline (pH = 10), weak (pH = 6) and strong acidic (pH = 2) conditions were investigated via the 13C-NMR method. Based on the proposed reaction mechanisms, the variations of the structures of different condensed products were analyzed and the competitive relationship between self- and co-condensation reactions was elucidated. The required experimental conditions for co-condensations were clearly pointed out. The main conclusions include: (1) the self-condensation between urea formaldehyde (UF) or phenol formaldehyde (PF) monomers were dominant while the co-condensations were very limited under alkaline conditions. This is because the intermediates produced from urea, methylolurea and phenol are less reactive in co-condensations with respect to self-condensations; (2) under weak acidic conditions, the self-condensations occurred exclusively among the UF monomers. The co-condensation structures were not observed; and (3) the co-condensations became much more competitive under strong acidic conditions as the relative content of the co-condensed methylenic carbon accounts for 53.3%. This result can be rationalized by the high reactivity of the methylolphenol carbocation intermediate toward urea and methylolurea. The revealed reaction selectivity and mechanisms may also be applied to the synthesis of those more complex co-condensed adhesives based on natural phenolic and amino compounds.
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Affiliation(s)
- Ming Cao
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
- College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China.
| | - Taohong Li
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
| | - Jiankun Liang
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
| | - Zhigang Wu
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
| | - Xiaojian Zhou
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
| | - Guanben Du
- The Yunnan Province Key Lab of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, China.
- College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China.
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7
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Zhao W, Gao H, Fan M. Synthesis of novel monolithic activated carbons from phenol–urea–formaldehyde resin. RSC Adv 2015. [DOI: 10.1039/c5ra20736c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Phenol–urea–formaldehyde (PUF) organic foams have been firstly synthesized from phenol–urea–formaldehyde resin under alkaline conditions, which can be used as precursor to produce cellular activated carbon foams.
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Affiliation(s)
- W. Zhao
- College of Material Engineering
- Fujian Agriculture and Forestry University
- Fuzhou 350002
- PR China
| | - H. Gao
- College of Material Engineering
- Fujian Agriculture and Forestry University
- Fuzhou 350002
- PR China
| | - M. Fan
- College of Engineering Design and Physical Sciences
- Brunel University
- UK
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Synthesis and Structure Characterization of Phenol-Urea-Formaldehyde Resins in the Presence of Magnesium Oxide as Catalyst. Polymers (Basel) 2014. [DOI: 10.3390/polym6082221] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Deng S, Du G, Li X, Pizzi A. Performance and reaction mechanism of zero formaldehyde-emission urea-glyoxal (UG) resin. J Taiwan Inst Chem Eng 2014. [DOI: 10.1016/j.jtice.2014.02.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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10
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Deng S, Pizzi A, Du G, Zhang J, Zhang J. Synthesis, structure, and characterization of glyoxal-urea-formaldehyde cocondensed resins. J Appl Polym Sci 2014. [DOI: 10.1002/app.41009] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Shuduan Deng
- College of Materials Science and Technology, Beijing Forestry University; Beijing 100083 People's Republics of China
- Yunnan key laboratory of wood adhesives and glue products; Southwest Forestry University; Kunming 650224 People's Republics of China
| | - Antonio Pizzi
- LERMAB, University of Lorraine 1; 27 Rue Philippe Seguin F-88000 Epinal France
- Department of Physics; King Abdulaziz University; Jeddah Saudi Arabia
| | - Guanben Du
- Yunnan key laboratory of wood adhesives and glue products; Southwest Forestry University; Kunming 650224 People's Republics of China
| | - Jizhi Zhang
- College of Materials Science and Technology, Beijing Forestry University; Beijing 100083 People's Republics of China
- LERMAB, University of Lorraine 1; 27 Rue Philippe Seguin F-88000 Epinal France
| | - Jun Zhang
- College of Materials Science and Technology, Beijing Forestry University; Beijing 100083 People's Republics of China
- LERMAB, University of Lorraine 1; 27 Rue Philippe Seguin F-88000 Epinal France
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11
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Deng S, Du G, Li X, Xie X. Performance, Reaction Mechanism, and Characterization of Glyoxal–Monomethylol Urea (G–MMU) Resin. Ind Eng Chem Res 2014. [DOI: 10.1021/ie404278d] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shuduan Deng
- Yunnan
Key Laboratory of Wood Adhesives and Glue Products, Southwest Forestry University, Kunming 650224, P.R. China
- College
of Materials Science and Technology, Beijing Forestry University, Beijing 100083, P.R. China
| | - Guanben Du
- Yunnan
Key Laboratory of Wood Adhesives and Glue Products, Southwest Forestry University, Kunming 650224, P.R. China
| | - Xianghong Li
- Yunnan
Key Laboratory of Wood Adhesives and Glue Products, Southwest Forestry University, Kunming 650224, P.R. China
- School
of Chemical Science and Technology, Yunnan University, Kunming 650091, P.R. China
| | - Xiaoguang Xie
- School
of Chemical Science and Technology, Yunnan University, Kunming 650091, P.R. China
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12
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Philbrook A, Earnshaw S, Easton CJ, Keniry MA, Latter MJ. Co-polymerization analysis of thermosetting resins using 1H- 15N- 13C triple resonance NMR spectroscopy. J Appl Polym Sci 2013. [DOI: 10.1002/app.38516] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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13
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Kibrik ÉJ, Steinhof O, Scherr G, Thiel WR, Hasse H. 13C-NMR,13C-13C gCOSY, and ESI-MS characterization of ether-bridged condensation products inN,N′-dimethylurea-formaldehyde systems. J Appl Polym Sci 2012. [DOI: 10.1002/app.38630] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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14
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Li TH, Wang CM, Xie XG, Du GB. A computational exploration of the mechanisms for the acid-catalytic urea-formaldehyde reaction: new insight into the old topic. J PHYS ORG CHEM 2011. [DOI: 10.1002/poc.1880] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Tao Hong Li
- The Key Laboratory of Forest Resources Conservation and Use in the Southwest Mountains of China; Southwest Forestry University; Kunming; 650224; China
| | - Chuan Ming Wang
- Department of Biology; Honghe University; Menzi; 661100; China
| | - Xiao Guang Xie
- Department of Chemistry; Yunnan University; Kunming; 650091; China
| | - Guan Ben Du
- The Key Laboratory of Forest Resources Conservation and Use in the Southwest Mountains of China; Southwest Forestry University; Kunming; 650224; China
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15
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Giovando S, Pizzi A, Pasch H, Rode K. Synthetic tannins structure by MALDI-TOF mass spectroscopy. J Appl Polym Sci 2009. [DOI: 10.1002/app.30667] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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16
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On the structure and cure acceleration of phenol–urea–formaldehyde resins with different catalysts. Eur Polym J 2009. [DOI: 10.1016/j.eurpolymj.2009.07.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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17
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Fan D, Chang J, Li J, Mao A, Zhang L. 13C-NMR study on the structure of phenol-urea-formaldehyde resins prepared by methylolureas and phenol. J Appl Polym Sci 2009. [DOI: 10.1002/app.29532] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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